compensacion

Introduction

In recent years, electrically controlled fuel injection systems and the latest emission after-treatment technologies are being rapidly introduced into diesel engines to achieve higher environmental and driving performance. In line with this trend, a high-level of ability to diagnose faults is required for service technicians. In addition, concurrent with recent progress in vehicle technology, the function of diagnostic tools (Intelligent Tester) has also been upgraded, and the diagnostic tool is becoming essential for the fault diagnosis which can be performed using the tool.

The utilization of diagnostic tools allows service technicians to efficiently perform fault diagnose. This reduces the vehicle service period and prevents re-service through a proper service, resulting in increasing customer satisfaction for the services and response quality.

This manual has been developed to cover from the basics of diesel engines to the latest electronic control technologies and effective diagnostic tool functions and the utilization methods.

Please read the manual carefully to deal with the progressing vehicle technology.

Intelligent Tester

Driv

ing

perfo

rman

ce

Environmental performance

Intelligent Tester

Turbocharger

DOHC 4-valve

Common-rail(135MPa)

Solenoid Injector

Common-rail(180MPa)

Piezo Injector

Common-rail (200MPa)

Oxidation Catalyst

Cooled EGR

Variable Nozzle Vane typeTurbocharger

Low Friction

DPF

DPNR

Low Comp. Ratio

Part 1

Description

1

2

Part 1

Description

1 Diesel Engine

Part 1 Description

Before learning how to diagnose faults in a diesel engine, let’s first learn the basics of the diesel engine in this chapter.

1 Diesel Engine1

Outline of Diesel Engine11 Diesel engines use diesel fuel (light oil) for running the engine, in which the fuel is self-ignited and ●

combusted under high temperature and pressure in the combustion chamber by compressing the intake air, giving a high compression ratio and thermal efficiency. Therefore, diesel engines are relatively superior to gasoline engines in fuel economy (lower CO2 emissions).The diesel engine uses a self-ignition combustion system, and this allows the combustion to occur ●

constantly at a high air ratio. In addition, the power output is controlled by adjusting the fuel injection amount, and which is different from that of gasoline engines. The fuel injected into the combustion chamber is ignited sequentially from a section in which the ●

combustion conditions (air ratio and temperature) are met in accordance with the injected fuel amount, regardless of the intake air amount. This is extremely different from gasoline engines, in which the combustion occurs by igniting the created air-fuel mixture. Therefore, in diesel engines, the control of the intake air amount is not required to control the output power and the throttle valve is also not required, thus reducing any pumping loss.

excess

excess

3

Part 1

Description

1 Diesel Engine

Principle of 4 Stroke Diesel Engine ■Intake valve

open

IntakeStroke

CompressionStroke

CombustionStroke

ExhaustStroke

Exhaust valveopen

Principle of 4 Stroke Gasoline Engine ■Intake valve

open

IntakeStroke

CompressionStroke

CombustionStroke

ExhaustStroke

Exhaust valveopen

4

Part 1

Description

1 Diesel Engine

Differences between diesel and gasoline engines ■Diesel Engine Gasoline Engine

Fuel

Diesel oil: The cetane number is a measure of the ignition performance.

Gasoline: The octane number is a measure of the resistance to knock.

Cetane number 48 or more Octane number 95 or more

Ignition point 330 to 350 °C 480 to 550 °CFlash point 45 to 80 °C -35 to -46 °C

Knock

This occurs when the fuel injected during the ignition delay period is ignited. This is more likely to occur the longer the ignition delay period is, or the more the fuel is injected during the ignition delay period.

This occurs when unburnt gas in the combustion chamber self-ignites under high temperature and pressure due to the combustion.

Fuel supply methodJerk method Carburetor method (Carburetor)Common rail method Fuel injection method

Combustion method Compressed self-ignition Spark ignitionCompression ratio 16 to 24 7 to 12

Air-fuel ratioStoichiometric air-fuel ratio: 14.6 Stoichiometric air-fuel ratio: 14.6Actual air-fuel ratio: 17.0 to 60.0 Actual air-fuel ratio: 10 to 17*1

Excess air ratio 1.2 to 4.0 0.6 to 1.2

Output control Control of fuel injection amount (AF: Not constant)

Control of intake air-fuel mixture amount (AF: constant)

Difference in combustion

Intake of atmospheric air Intake of air-fuel mixture*2

Self-ignites causing an ignition delay after the fuel is ignited under high temperature and pressure (Vicinity of Top Dead Center).

Spark ignition (before Top Dead Center)

Premix combustion (not-controlled), in which the fuel injected during the ignition delay period is combusted rapidly, and dif fusive combustion (controlled) after the direct combustion period

Flame propagating from the ignition point (Controlled)

*1: Except stratification combustion*2: Except D-4 engine

5

Part 1

Description

1 Diesel Engine

Type of Diesel Engine21 There are various diesel engine types depending on the combustion chamber shape, fuel injection ●

method and emission treatment method.The differences among the types are outlined in the table below. ●

1997

2C-T

2C-TE

2AD-FTV

2AD-FHV

(w/o DPF)1AD-FTV

1AD-FTV(w/DPF)

1CD-FTV(w/DPNR)

1CD-FTV

1998 1999 2005 20062000 ~ 2004

Diesel engine for passenger vehicles (AVENSIS) ■Engine Type 2C-T 2C-TE 1CD-FTV 1AD-FTV 2AD-FHV

Release date Oct., ‘97 ← Aug., ‘99 Apr.,’06 (w/o DPF)

Aug.,’06 (w/ DPF) Apr., ‘05

Destination Europe ← ← ← ←No. of Cyls. & Arrangement

4-Cylinder, In-Line ← ← ← ←

Valve mechanism

8-Valve, OHC,

Belt Drive←

16-Valve,DOHC, Chain

and Gear Drive← ←

Combustionchamber Swirl Type ← Direct Injection

Type ← ←

Fuel system

Jerk Method(Mechanical type)

Jerk Method(Electric control

type)

Common-rail Type (HP2)

Common-rail Type (HP3) ←

Mechanical InjectionNozzle ← Solenoid Type

Injector ← Piezo TypeInjector

Displacementcm3 1975 ← 1995 1998 2231

Bore X Strokemm 86.0 X 85.0 ← 82.2 X 94.0 86.0 X 86.0 86.0 X 96.0

Compressionratio 23.0 : 1 ← 18.6 : 1 16.8 : 1 15.8 : 1

Max. outputEEC

60 kW @4000 rpm

66 kW @4000 rpm

81 kW @4000 rpm

93 kW @3600 rpm

130 kW @3600 rpm

Max. torqueEEC

170 Nm@2000-

3000 rpm

203 Nm @2200 rpm

250 Nm @2000-

2400 rpm

300 Nm @

2000-2800 rpm

300 Nm @

1800-2400 rpm

400 Nm @2000-

2600 rpm

Catalytic converter Oxidation Oxidation Oxidation +DPF

Oxidation

+NSR+DPNR

OxidationEmissionregulation EURO 2 EURO 3 EURO 4 ←

6

Part 1

Description

1 Diesel Engine

Enlargement of diesel engine market31

Outline[1[ By use of the latest engine control technologies such as the common-rail system and improvement in ●

the emission treatment technologies, emission gases such as PM and NOx, which are considered to be shortcomings have been reduced while maintaining a low fuel consumption rate, which are seen as the maximum benefits and the engine output power has been increased, leading to clean and powerful engines exceeding gasoline engines. Accordingly, the current European market share of diesel engines is near 50%, however, it was only approximately 10% in 1990.

Market share of diesel passenger vehicles ■

Market introduction of common rail diesel

1985 1990 1995 2000 2005

(Years)

50

45

30

20

15

10

0

Market share transition by output power ■

0%

10%

20%

30%

40%

50%

1999

115hp or less

116hp or more

2000 2001 2002 2003 2004 2005

7

Part 1

Description

1 Diesel Engine

Emission Regulation in Europe[2[ Exhaust emission regulations based on the EC Directive have been introduced in Europe (EC ●

member countries). In 1992, passenger vehicles belonging to the M1 category were only required to be in compliance with the EURO1 standard and as the regulations have been made stricter in the past few years, the vehicles are now in compliance with the EURO4 standard in 2008.

EURO4

EURO4

EURO4

EURO4

500

300

250

250

EURO1

EURO1

EURO1

EURO1

2720

970

No regulation

1400

EURO5

EURO5

EURO5

EURO5

500

230

180

50

EURO2

EURO2

EURO2

EURO2

1000

700

No regulation

800

EURO6

EURO6

EURO6

EURO6

(mg/km)

(mg/km)

(mg/km)

(mg/km) x 10

500

170

80

50

EURO3

EURO3

EURO3

EURO3

CO

HC + NOx

NOx

PM

640

560

500

500

Emission standards for diesel passenger vehicles ■Emission Standard CO(g/km) HC + NOx(g/km) NOx(g/km) PM(g/km)EURO1 (1992/07) 2.72 (3.16*1) 0.97 (1.13*1) - 0.14 (0.18*1)EURO2 (1996/01) 1.0 0.7*2, 0.9*3 - 0.08*2, 0.1*3

EURO3 (2000/01) 0.64 0.56 0.5 0.05EURO4 (2005/01) 0.5 0.3 0.25 0.025EURO5 (2009/09) 0.5 0.23 0.18 0.005EURO6 (2014/09) 0.5 0.17 0.08 0.005

*1: COP (Conformity Of Production) value*2: Except Direct Injection type Diesel Engine (Swirl Chamber type and Precombustion Chamber type)*3: Direct Injection type Diesel Engine

8

Part 1

Description

1 Diesel Engine

Type of Combustion Chamber41

General[1[ The combustion chamber of a diesel engine is the single most important component for determining ●

diesel engine performance. Various chamber configurations have been developed an attempt to enhance diesel engine performance by making sure that the fuel injected into the chamber atomizes, vaporizes, and mixes evenly with the air: Methods used include using a specially formed intake port in the cylinder head to generate an air swirl inside the cylinder, or adding an auxiliary combustion chamber which exploits the gas expansion at the initial ignition stage to help improve the combustion efficiency. The combustion chambers currently in use on vehicles are:

Direct Combustion Chambers Direct Injection Type

Diesel Combustion Chambers

Auxiliary Combustion Chambers Swirl Chamber Type

Direct Injection Type[2[

Outline<1< A main combustion chamber is provided between the cylinder head and the piston, in which the fuel ●

is directly injected into the combustion chamber from the injection nozzle/injector. Ultra-high pressure injection via the common-rail system, porous injection nozzle/injector, and specially shaped pistons are used, as air and fuel are mixed by the fuel injection from the injection nozzle/injector and the squish on the piston upper face.

Advantages<2< A direct-injection type combustion chamber has a small surface area, and this reduces thermal loss, ●

giving a high fuel economy and output power. No pre-heating devices are required when starting the engine at normal temperature since it has excellent ignition performance.

9

Part 1

Description

1 Diesel Engine

Disadvantages<3< A high injection pressure is required to improve fuel atomization, and this requires high strength from ●

the fuel system.Diesel engines have a high internal combustion pressure, creating a loud combustion noise, and ●

which is apt to induce knocking in the engine. In comparison with a swirl chamber type, the direct injection type has a weaker swirling flow, causing the intake air to not be fully utilized, which results in a lower maximum engine speed.These disadvantages have been improved in engines which employ the common-rail system. ●

In recent years, diesel engines are equipped with a common-rail system that can inject ultra-highly ●

pressurized fuel at any time plunger as well as at multiple steps thanks to the electronically controlled injectors.Use of the common-rail system has allowed diesel engines to improve fuel combustion and achieve ●

the optimal combustion according to the engine operating conditions. As a result, the common-rail diesel engines have successfully made the typical problems described earlier less severe to a considerable extent.

TIP

10

Part 1

Description

1 Diesel Engine

Swirl Chamber Type[3[

Outline<1< Basically, a spherical swirl chamber, which is connected by holes to the main combustion chamber, ●

is provided. During the compression stroke, air is introduced into the swirl chamber, creating a strong swirl motion. By injecting the fuel in the swirl chamber, air and fuel are fully mixed and combusted rapidly, injecting the air-fuel mixture into the main combustion chamber.

Advantages<2< Air introduced by the swirl motion can be fully utilized, and this increases the maximum engine speed. ●

In addition, a high injection pressure like in the direct injection type diesel engine is not required, and which reduces any fault arising from the fuel systems.

Disadvantages<3< A pre-heating device is required, and knocking is apt to easily occur at low speeds since the cylinder ●

head has a large surface area.

11

Part 1

Description

1 Diesel Engine

Diesel Engine Combustion51

Combustion Process[1[

Outline<1< In gasoline engines, a uniformly premixed air-fuel mixture is combusted. By contrast, in diesel ●

engines, non-uniformly mixed fuel droplets, vapor and ambient air are combusted.When the fuel is atomized under high temperature air conditions, the fuel in the combustion chamber ●

is heated and vaporized by the heat of the surrounding chamber, forming a combustion mixture and igniting a part of the fuel. This rapidly increases the temperature and pressure in the combustion chamber and causes the remaining fuel to be vaporized, mixed and combusted rapidly.

80

60

40

20

0

Fuel Pressure [kg/cm2]

-40°

E

D

C

BA

-20° TDC 20° 40°

A→B Ignition delay period (Combustion preparation period)B→C Flame propagation period (Constant volume combustion period)C→D Direct combustion period (Constant pressure combustion period)D→E After burning period (Latter combustion period)

Ignition delay period (A to B)<2< This covers the period from when the fuel is injected into the combustion chamber at point A to ●

when it is ignited at point B. This is also referred to as the combustion preparation period, in which the injected fuel droplets are heated and vaporized by the surrounding high temperature air and compressed air, and the fuel are mixed and heated up to the ignition temperature, forming a mixed gas. The period is very short, and is governed by the pressure, temperature, fuel particle size, dispersion state and air swirling state in the combustion chamber. An increase in the internal cylinder pressure can barely be observed in this period. However, the length of the period strongly affects the subsequent combustion.

Flame propagation period (B to C)<3< The ignition starts from the area with the optimum air-fuel ratio in the mixed gas which was generated ●

and accumulated during the ignition delay period. Subsequently, most of the remaining accumulated mixed gas is combusted at the same time, increasing the internal cylinder pressure and temperature instantaneously. The increase in the pressure and temperature at this time is affected by the fuel amount which was injected during the ignition delay period, swirl motion of the atomized air and the air-fuel mixture, and the fuel, which was injected at point B, is mostly combusted during this period.

12

Part 1

Description

1 Diesel Engine

Direct combustion period (C to D)<4< The fuel is injected even after point C shown in the illustration below. However, once the combustion ●

starts in the cylinder, the internal cylinder pressure and temperature increase dramatically. Therefore, the fuel which is injected from the injection nozzle/injector is combusted very quickly once they are mixed. During this period, the internal pressure and temperature can be controlled by adjusting the fuel injection amount.

After burning period (D to E)<5< The fuel injection into the cylinder stops at the point D shown in the illustration below. However, large ●

unburnt fuel droplets and areas that were not fully combusted because the air and fuel were not fully mixed due to oil particle density at point D are mixed with air, and combusted during the inflation stroke, from the point D to E.The fuel combustion processes described above are summarized as follows. The ignition delay period ●

and the flame propagation period can be referred to as a preparation period for the direct combustion period in other words. To activate the direct combustion period, which is featured by the diesel engine, it is said that reducing the increase in the pressure during the flame propagation period is preferable.

Excess air ratio[2[ It is said that an adequate amount of air is necessary to completely burn the fuel through combustion, ●

and the optimum air-fuel ratio for diesel fuel is 14.3:1. In other words, 14.3kg of air is required to completely burn 1kg of diesel oil.However, in diesel engines, the mixing time for the air and fuel is very short as the fuel is directly ●

injected in the combustion chamber, and this causes some air to not fully mix with fuel, leaving the unmixed air in the chamber. If the theoretically necessary amount of air is not introduced in the cylinder, only the oxygen around the injected fuel is likely to be combusted, causing a lack of oxygen. Therefore, more air than the theoretically required amount of air is required to be introduced to completely combust the injected fuel.The ratio between the actual intake air amount and theoretical air amount necessary for a complete ●

combustion is called excess air ratio.Generally, the air ratio of the diesel engine is approximately 1.2 to 1.3 at full load (maximum injection ●

amount) and approximately 3.0 to 4.0 at a low speed and light load (small injection amount).

Excess air ratio =Actual intake air amount (weight)

Theoretical air amount necessary for complete combustion (weight)

13

Part 1

Description

1 Diesel Engine

Exhaust emission characteristics[3[ Since diesel engines have the property that the air ratio is higher, thus, even without a catalytic ●

converter, the emission level of CO and HC is equivalent to that of gasoline engines.However, since NOx reduction devices such as a three-way catalytic converter are unable to be used ●

due to the high air ratio, the reduction of NOx emissions is not easy to achieve.　If the combustion temperature is decreased by the EGR in order to reduce the NOx emission, the amount of PM emissions increases.The emission regulation also requires a substantial reduction of those conflicting substances. ●

Therefore, in order to reduce the trade-off NOx and PM emissions, recent diesel engines use the ●

common-rail system to optimize the fuel injection control, and employ DPF (Diesel Particulate Filer) and DPNR (Diesel Particulate NOx Reduction System) to enhance the fuel combustion and emission treatment. (Refer to TOYOTA D-CAT)

Emission component

Diesel Engine GasolineEngine

+Three-way Catalytic Converter

Common-rail+

DPNR

Common-rail+

DPF

Common-rail+

Oxidation Catalytic Converter

Jerk

CO2

CO

HC

NOx

PM

Reduction of NOx and PM ■

EURO2*

EURO4

PM (g/km)

EURO6

EURO1*

EURO3

EURO5

NOx (g/km)

* NOx + HC

14

Part 1

Description

1 Diesel Engine

Output Control[4[ In gasoline engines, throttle valves increase/decrease the air-fuel mixture amount introduced from the ●

engine, thus adjusting the engine output. However, in diesel engines, the intake air amount is constant as there are no throttle valves, therefore, the engine output is controlled by adjusting the fuel amount to be injected.

Diesel Engine ■High Power Output

Low Power Output

Gsoline Engine ■

Low Power Output

High Power Output

15

Part 1

Description

1 Diesel Engine

Problems due to fuel combustion conditions[5[

Diesel knock<1< The fuel, which was accumulated during the ignition delay period, burns rapidly in the flame ●

propagation period, thus, the pressure inside the combustion chamber will rise sharply.The more fuel is injected during the ignition delay period, the larger the extent of the sharp increase ●

in the combustion chamber internal pressure, and this pressure wave vibrates all parts of the engine, causing the noise. This is what known as diesel knock, and is unavoidable to a certain extent in diesel engines due to the spontaneous fuel combustion initiated by self ignition.The possible causes of the diesel knock are; long ignition delay period, low engine temperature, low ●

intake air temperature, high fuel ignition temperature, early injection timing, or poor fuel atomization. (For details, refer to the case study on page @)

Fuel Injection Start

Knocking

Normal Combustion

16

Part 1

Description

1 Diesel Engine

White smoke<2< White smoke emission is considered to be the result of unburned fuel vapor due to relatively low ●

combustion temperatures.The possible causes of white smoke are; late fuel ignition timing or faulty after-glow in low ●

temperatures. (For details, refer to the case study on page @)

Black smoke<3< Black smoke emission is considered to be the result of the incomplete combustion of fuel molecules ●

due to insufficient oxygen. This results in soot.　Simply, only the outside of a droplet of fuel oil burns but the central part cannotThe possible causes of black smoke are; excessive fuel injection volume, insufficient intake air ●

volume, early fuel ignition timing, or poor fuel atomization. (For details, refer to the case study on page @)

17

Part 1

Description

2 Three elements of a diesel engine

2 Three elements of a diesel engine2

Necessary conditions to run a diesel engine11

Outline[1[ To run the engine efficiently, a fuel system, compression, and glow system play critical roles in diesel ●

engines, while air-fuel mixtures, sparks and compression are the three important elements to gasoline engines.

Fuel system[2[ Diesel engines do not have throttle valves that are used in gasoline engines. The output of a diesel ●

engine is regulated by the amount of fuel injected, while that of a gasoline engine is regulated with a throttle valve. In addition, since the combustion begins by injecting fuel, the fuel injection timing is also regulated. This corresponds to the ignition timing control of a gasoline engine.

Output is regulated by fuel injection volume Fuel injection timing is also regulated

Currently, throttle valves are provided on a large number of TOYOTA diesel engines. However, these throttle valves are used to ensure the EGR and reduce white and black smoke, vibrations and noise by opening/closing the valves in accordance with the engine conditions, not to control the output power as in gasoline engines.

TIP

18

Part 1

Description


Compression[3[ By compressing air, the pressure prepared for the combustion can be increased. This is also applied ●

to gasoline engines. Additionally, in diesel engines, the intense heat that ignites the fuel is produced by the compressed air. The compression of diesel engines corresponds to the spark plug firing of gasoline engines.

Intense heat that is necessary for ignition is produced Combustion pressure is boosted

Glow system[4[ The glow system is a distinctive device of diesel engines. Diesel engines need to generate sufficient ●

heat to burn fuel. If an engine is cold, the compression heat is difficult to be obtained, thus, a device (glow system) that aids the heat generation is necessary.

Compression heat is supplied when engine is cold

19

Part 1

Description


Fuel System21

Outline of Fuel System[1[ There are two types of fuel systems; the conventional system and the common-rail system. ●

Type Conventional system Common-rail systemFuel

supply Distributor injection pump Distributor electrically controlled injection pump Supply pump

Injector

Injection nozzle (mechanical automatic valve) Injector (electromagnetic)The plunger inside the injection pump pressurizes the fuel and feeds it to the injection nozzle, and when the fuel pressure reaches the specified pressure level, the internal valve of the nozzle is pushed up, injecting the fuel.

The common-rail stores the fuel which has been highly pressurized and fed by the supply pump, and the ECM electrically opens the injector valve to inject the fuel.

Injection pressure Nozzle open pressure(15MPa/Constant)

Common-rail internal pressure (Approx. 200 MPa/ECM regulates according to the engine operating conditions)

Injection volume

Regulated by the governor and the degree to how much the accelerator pedal is depressed.

The ECM regulates i t by contro l l ing the end of injection with the spill control valve.

The ECM regulates it by controlling the duration that the injector valve is open.

Injection timing

Regulated by the automatic timer.

The ECM regulates i t by controlling the timing control valve.

The ECM regulates it by controlling the timing of when the injector valve opens.

Conventional Type[2[

General<1< There are two types of injection pumps for the conventional system, one is VE pumps and the other is ●

in-line pumps. VE pumps are compact and light-weight, and are usually used on passenger vehicles. In-line pumps are relatively big and heavy compared to the VE pumps, thus, they are used primarily on trucks.Furthermore, the VE pump can be classified into two different types: mechanical pumps and ●

distributor electrically controlled injection pumps.

<IN-LINE TYPE PUMP>

Mechanical Type Electric Type

<VE TYPE PUMP>

20

Part 1

Description


Distributor injection pump<2< Fuel injection systems equipped with a mechanical distributor injection pump consist mainly of an ●

injection pump (governor and timer piston) and injection nozzles.

System Diagram ■

Fuel Filter

Fuel Cut Off Solenoid

Spill Ring

Feed Pump Pump Plunger

Fuel Tank

Injection Nozzle

Governor

Timer Piston

Outline of control ■Control Outline

Injection volume control

The governor reacts to the degree of the accelerator pedal depression and the engine speed, and the spill ring is allowed to operate, thus, regulating the amount of fuel injected.

Injection timing control

The fuel pressure rises as the engine revs up, and that pressure causes the timer piston to operate, regulating the fuel injection timing.

Injection control The fuel, which is highly pressurized by the injection pump, pushes the needle of the injection nozzle up, regulating the fuel injection.

21

Part 1

Description


Distributor electrically controlled injection pump<3< Fuel injection systems equipped with a distributor electrically controlled injection pump consist mainly ●

of an injection pump (spill control valve and timing control valve), injection nozzles, and an ECM.

System Diagram ■

Fuel Filter

Spil Control Valve

Timing Control valve

Feed PumpPump Plunger

Fuel Tank

Injection Nozzle

ECM


Injection volume control

Depending on the engine conditions that are monitored by the sensors, the ECM calculates the optimal injection volume, and regulates the amount of fuel injected using the spill control valve.

Injection timing control

By referring to the degree of the accelerator pedal depression, engine speed, and engine conditions that are monitored by the sensors, the ECM calculates the optimal injection timing, and regulates the injection timing using the timing control valve.

Injection control The fuel, which is highly pressurized by the injection pump, pushes the needle of the injection nozzle up, regulating the fuel injection.

22

Part 1

Description


Common - rail Type[3[

General<1< There are three types of injection pumps, HP2, HP3 and HP4, for the common-rail system. HP2 and ●

HP3 pumps are used on vehicles with a small displacement engine, and HP4 pumps are used on vehicles with a large displacement engine.In addition, two types of injectors, solenoid and piezo, are available. ●

HP2 Type HP3 Type HP4 Type

Common-rail system<2< Fuel injection systems equipped with a common-rail system consist mainly of a supply pump (suction ●

control valve), a common-rail, injectors, EDU, and an ECM.

System Diagram ■

Supply Pump

Common-rail

Fuel Tank

EDUFuel Filter

ECM

Injector


Injection volume control Based on the signals received from the sensors, the ECM determines the fuel injection volume in accordance with the engine operating conditions.

Injection timing control Based on the signals received from the sensors, the ECM determines the fuel injection timing in accordance with the engine operating conditions.

Injection controlBased on the calculated injection amount and injection period, the ECM injects the highly-pressurized fuel which has accumulated in the common-rail by controlling the injector valve to open through the EDU.

23

Part 1

Description


Glow System31

Outline of Glow System[1[ The glow system, where the fuel ignition performance is enhanced by warming up the combustion ●

chamber using a glow plug, has been replaced with an electric control system which controls the glow plug temperature by controlling energization to the conventional glow plug using main and sub relays. Thus, a self-control system in which the glow plug is equipped with a self-temperature control function is used.The glow plugs are fitted in the cylinder head, and the built-in heaters are heated when the plugs are ●

energized. In diesel engines, either the metal or ceramic glow plugs is used generally.

Glow SystemCurrent Previous

Self-control type Electric control type

Type of Glow PlugMetal

MetalCeramic

Number of relay 1 relay used (Main Relay) 2 relay used (Main Relay / Sub Relay)

Glow Plug Resistor None Used

Voltage applied to the glow plugPreheating: Battery Voltage Preheating: Battery voltageAfter-glow: Battery Voltage After-glow: Low Voltage

Glow Plug[2[

Metal Glow Plug<1< The metal glow plug consists of metal heater coils and has temperature characteristics of ●

approximately 900 degrees.The metal glow plug has two types: Self-control type in which the glow plug temperature is self- ●

controlled, and the conventional type in which the glow plug temperature is controlled by the energizing system.The self-control type glow plug has a built-in control coil that increases its resistance with the increase ●

in the temperature of the glow plug. The increased resistance of the control coil then reduces the voltage that is applied to the thermal coil and the heating element that is connected in series to the control coil. In this manner, the glow plug itself provides the function to reduce its own temperature.

Thermal Coil

Control Coil

Self-control type glow plug

1000

05

Tem

pera

ture

(˚C

)

Energization duration (sec)

Self-control typeElectric control type

24

Part 1

Description


Ceramic Glow Plug<2< The ceramic glow plug consists of ceramic heater elements and has temperature characteristics of ●

approximately 1,200 degrees and excellent temperature increase characteristics.The ceramic glow plug is a self-control type glow plug which does not require temperature control by ●

the energizing system.

Heating element (conductive

ceramic)

Insulating element (insulation ceramic)

Lead wire1200

Ceramic glow plugMetal glow plug

015 30

Tem

pera

ture

(˚C

)

Energization duration (sec)

Energizing system[3[

Electric control type<1< In the electric control type, the preheating time (main and sub being ON period) and the after-glow ●

time (sub relay being ON period) are controlled on the basis of the engine coolant temperature and the glow plug temperature which is determined by the current sensor. (Whereas, on models using the self-control type glow plug, the preheating time and the after-glow time are controlled on the basis of the engine coolant temperature and the voltage applied to the glow plug terminal.)

25

Part 1

Description


ECM

Engine Coolant Temperature Sensor

Current Sensor

Glow Plug Sub Relay

Glow Indicator LampGlow Plug

Register

Glow Plug

Ignition Switch

Battery

Glow Plug Main Relay

Self-control type<2< In the self-control type, the preheating time and the after-glow time (main relay being ON period) are ●

controlled on the basis of the engine coolant temperature.

ECMEngine Coolant

Temperature Sensor

Glow Plug Relay Glow Indicator

Lamp

Glow Plug

Ignition Switch

Battery

Part 2

Common-railDiesel Engine

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1 Common-rail Diesel Engine

Part 2 Common-rail Diesel Engine

In this chapter, you will learn about the common-rail system --- leading-edge technology of the electronically controlled fuel injection system for diesel engines, the relevant electronic control technologies, and the troubleshooting methods for the components/parts and control systems.

1 Common-rail Diesel Engine3

Description11 The common-rail system is an electronically controlled fuel injection system which has been launched ●

by Denso for practical use in 1995 for the first time.The common-rail system accumulates high-pressure fuel supplied from the supply pump in the ●

common-rail and injects the fuel using the electronically controlled injectors.Since the common-rail system can accurately control the fuel injection volume and injection timing via ●

the ECM, and can maintain a stable injection pressure even when the engine speed is unstable, such as a low engine speed, the reduction of the diesel engine-specific black smoke and the vibration/noise resulting from the combustion is possible.Toyota has named the diesel engine system Toyota D-4D (Direct injection 4-stroke common-rail ●

Diesel engine), in which the common-rail system is combined with the direct injection combustion chamber that helps minimize heat loss, resulting in good fuel economy and high power output.Toyota D-4D can be divided into 3 major generations depending on the supply pumps and the exhaust ●

emission treatment methods.

Diesel EFI

2nd-generationHP3/HP4 Supply ●PumpSolenoid Injector ●Oxidation Catalytic ●Converter Max. 135-160 MPa

3rd-generationHP3/HP4 Supply ●PumpPiezo Injector ●DPNR/DPF ●Max. 160-200 MPa

1st-generationHP2 Supply Pump ●Solenoid Injector ●Oxidation Catalytic ●Converter Max. 135 MPa

Common-rail

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Common-rail Diesel Engine Control list ■System Outline

Fuel Pressure ControlBased on the signals received from the sensors, the ECM determines the appropriate fuel pressure in accordance with the engine operating conditions.

Fuel Injection Volume ControlBased on the signals received from the sensors, the ECM determines the appropriate fuel injection volume in accordance with the engine operating conditions.

Fuel Injection Timing ControlBased on the signals received from the sensors, the ECM determines the appropriate fuel injection timing in accordance with the engine operating conditions.

Multiple Injection ControlBased on the signals received from the sensors, the ECM performs up to five injections; Pilot-, Pre-, Main-, After-, and Post-injection in accordance with the engine operating conditions.

After-treatment ControlBased on the signals received from the sensors, the ECM adds fuel to the engine combustion control and exhaust systems to purify PM (DPF/DPNR), sulfur (PNF) and NOX (DPNR).

Swirl ControlBased on the signals received from the sensors, the ECM determines the appropriate swirl control valve position in accordance with engine operating conditions.

EGR Control Based on the signals received from the sensors, the ECM determines the appropriate EGR volume in accordance with the engine condition.

Diesel Throttle Control

Based on the signals received from the sensors, the ECM determines the appropriate throttle position in accordance with engine operating conditions.Fully close the diesel throttle control valve in order to reduce vibration when the engine is stopped.

Turbocharger Control Based on the signals received from the sensors, the ECM determines the appropriate nozzle vane position in accordance with the engine condition.

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TOYOTA D-CAT21

Outline[1[ The TOYOTA D-CAT has successfully achieved low emissions and good fuel economy simultaneously, ●

and is the concept engine putting all of Toyota’s modern clean diesel technologies together, and is the integration of the engine control, combustion control, high-pressure common-rail injection and newly-developed catalytic converter.Simultaneously, NOx and combustion noise is reduced and CO and HC are emitted instead. The CO ●

and HC emissions and the exhaust temperature rise due to the reduction in the air volume for making the air-fuel ratio rich allows the converter bed temperature to be high enough as to keep the catalytic converter active enough under low load driving conditions.

TOYOTA D-CAT Conceptual Drawing ■

Engine Management

Fuel Injection Combustion

Catalytic Converter

Exhaust-port Injection ●Multi-injection ●Feedback Control ●EGR Control ●

High-pressure Common- ●rail

Low Temperature ●Combustion

DPNR ●DPF ●

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Combustion Control[2[

Low-temperature Combustion<1< In conventional diesel engines, more smoke is emitted because the increase of EGR causes a ●

decrease in the oxygen volume. However, adoption of a highly efficient EGR system and further increase in the amount of EGR by the fuel injection timing control make the air-fuel ratio rich, which decreases the ambient combustion temperature and drastically decreases the smoke emissions. Simultaneously, NOx and combustion noise is reduced and CO and HC are emitted instead. The CO ●

and HC emissions and the exhaust temperature rise due to the reduction in the air volume for making the air-fuel ratio rich allows the converter bed temperature to be high enough as to keep the catalytic converter active enough under low load driving conditions.

Air Fuel RatioLean

EGR Volume

Stoichiometric

Low Temp.Combusion Area

NormalCombustion Area

: Smoke: NOx: CO/HC

Rich

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DPF (Diesel Particulate Filter)[3[ The DPF is an exhaust gas purification system that treats PM, as well as the HC and CO emitted from ●

diesel engines. The DPF consists of a DPF catalyst that is a structure of porous ceramics with a PM trapping function and an oxidation catalyst function, a common-rail system, an EGR system, and fuel addition into the exhaust system.


DPF

DPNR (Diesel Particulate - NOx Reduction System)[[[ The DPNR is an exhaust gas purification system that treats PM and NOx simultaneously, in addition ●

to HC and CO emitted from diesel engines. The DPNR consists of a DPNR and NSR catalyst that is the combination of a porous ceramic structure with a PM trapping function and a NOx storage reduction catalyst, a common-rail system, an EGR system, and fuel addition into the exhaust system.

DPNR+

NSR


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2 Variation[

CD Series Engine11

Engine Specification[1[ Engine 1CD-FTV (*1) 1CD-FTV (*2) 1CD-FTV (*3)

Model CDT220, CLM20CDE110/120, CLA2#

CDT250, CDE120CUR10 CDT250

Catalytic Converter Oxidation Catalytic Converter


DPNR + Oxidation Catalytic Converter

Supply Pump HP2 HP3 HP3

Fuel Pressure

Pressurizing SCV X 2 SCV X 1 SCV X 1

Depressurizing Pressure Limiter Pressure Discharge Valve

Pressure Discharge Valve

Max. Pressure 135MPa 160MPa 175MPaFuel Pressure

Sensor Single Element Twin Element Twin Element

Fuel InjectorType Solenoid Solenoid Solenoid

Compensation Resister QR Code QR CodeExhaust Fuel Addition Injector Not Available Not Available Available

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2 Variation

System Diagram[2[ 1CD-FTV (*1) ■

ECM

EDU

1

2

34

5

6

7

8

9

10

111213

1415

1617

18

19 20

1 Intake Air Temperature Sensor 11 Fuel Injector2 Air Flow Meter 12 Glow Plug3 Inter Cooler 13 Engine Coolant Temperature Sensor4 Intake Air Temperature Sensor 14 Crankshaft Position Sensor5 Diesel Throttle 15 Fuel Tank6 Manifold Absolute Pressure Sensor 16 Fuel Filter7 VSV (for Atmosphere Pressure Sensor) 17 Supply Pump (HP2)8 EGR Valve 18 Common-rail9 Variable Nozzle Vane Turbocharger 19 Fuel Pressure Sensor10 Camshaft Position Sensor 20 Pressure Limiter

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1CD-FTV (*2) ■

ECM

EDU

1

2

34

5

6

7

17

18 20

89

10

1112

13

1415

16

19

1 Intake Air Temperature Sensor 11 Fuel Injector2 Air Flow Meter 12 Glow Plug3 Inter Cooler 13 Engine Coolant Temperature Sensor4 Intake Air Temperature Sensor 14 Crankshaft Position Sensor5 Diesel Throttle 15 Fuel Tank6 Manifold Absolute Pressure Sensor 16 Fuel Filter7 EGR Valve 17 Supply Pump (HP3)8 EGR Cooler 18 Common-rail9 Variable Nozzle Vane Turbocharger 19 Fuel Pressure Sensor10 Camshaft Position Sensor 20 Pressure Discharge Valve

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2 Variation

1CD-FTV (*3) ■

ECM

EDU

1

2

34

5

6

78

24

9

23

10

1112

13 22

14

1516

17

18

19 21

20

1 Intake Air Temperature Sensor 13 Glow Plug2 Air Flow Meter 14 Engine Coolant Temperature Sensor3 Inter Cooler 15 Crankshaft Position Sensor4 Intake Air Temperature Sensor 16 Fuel Tank5 Diesel Throttle 17 Fuel Filter6 Manifold Absolute Pressure Sensor 18 Supply Pump (HP3)7 EGR Valve 19 Common-rail8 EGR Cooler 20 Fuel Pressure Sensor9 Variable Nozzle Vane Turbocharger 21 Pressure Discharge Valve10 Camshaft Position Sensor 22 Differential Pressure Sensor11 Exhaust Fuel Addition Injector 23 Exhaust Temperature Sensor12 Fuel Injector 24 Air-fuel Ratio Sensor

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AD Series Engine21

Engine Specification[1[

Engine 1AD-FTV2AD-FTV (*1)

1AD-FTV 2AD-FTV (*2) 2AD-FHV (*3)

Model ADT25#ALA30, AUR10

ADT250, ADE150ALA30, AUR10

ADT251, ADE157ALA30, AUR10, ALE20

Catalytic Converter Oxidation Catalytic Converter

DPF + Oxidation Catalytic Converter

DPNR + Oxidation Catalytic Converter

Supply Pump HP3 HP3 HP3

Fuel Pressure

Pressurizing SCV X 1 SCV X 1 SCV X 1

Depressurizing Pressure Limiter Pressure Limiter Pressure Discharge Valve

Max. Pressure 160MPa (1AD-FTV)170MPa (2AD-FTV)

160MPa (1AD-FTV)170MPa (2AD-FTV) 180MPa

Fuel Pressure Sensor Single Element Single Element Twin Element

Fuel InjectorType Solenoid Solenoid Piezo

Compensation QR Code QR Code QR CodeExhaust Fuel Addition Injector Not Available Available Available

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2 Variation

System Diagram[2[ 1AD-FTV, ■ 2AD-FTV (*1)

ECM

EDU

1

2

3

4

5

6

7 8

9

10

1112

13

1415

16 17

18

1921

20

1 Intake Air Temperature Sensor 12 Glow Plug2 Air Flow Meter 13 Engine Coolant Temperature Sensor3 Inter Cooler 14 Crankshaft Position Sensor4 Intake Air Temperature Sensor 15 Fuel Tank5 Diesel Throttle 16 Fuel Filter6 Manifold Absolute Pressure Sensor 17 Fuel Cooler7 EGR Valve 18 Supply Pump (HP3)8 EGR Cooler 19 Common-rail9 Variable Nozzle Vane Turbocharger 20 Fuel Pressure Sensor10 Camshaft Position Sensor 21 Pressure Limiter11 Fuel Injector

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1AD-FTV, ■ 2AD-FTV (*2)

ECM

EDU

1

2

34

5

67

89

10

25

11

12 1314

2415

16

17

18 19

2123

26

22

20

1 Intake Air Temperature Sensor 14 Glow Plug2 Air Flow Meter 15 Engine Coolant Temperature Sensor3 Inter Cooler 16 Crankshaft Position Sensor4 Intake Air Temperature Sensor 17 Fuel Tank5 Diesel Throttle 18 Fuel Filter6 Manifold Absolute Pressure Sensor 19 Fuel Cooler7 EGR Valve 20 Supply Pump (HP3)8 EGR Cooler 21 Common-rail9 VSV (for EGR Cooler Bypass Valve) 22 Fuel Pressure Sensor10 Variable Nozzle Vane Turbocharger 23 Pressure Limiter11 Camshaft Position Sensor 24 Differential Pressure Sensor12 Fuel Injector 25 Exhaust Temperature Sensor13 Exhaust Fuel Addition Injector 26 Air-fuel Ratio Sensor

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2 Variation

2AD-FHV (*3) ■

ECM

EDU

1

2

34

5

67

89

10

25

11

12 1314

2415

16

17

18 19

21 23

26

22

20

1 Intake Air Temperature Sensor 14 Glow Plug2 Air Flow Meter 15 Engine Coolant Temperature Sensor3 Inter Cooler 16 Crankshaft Position Sensor4 Intake Air Temperature Sensor 17 Fuel Tank5 Diesel Throttle 18 Fuel Filter6 Manifold Absolute Pressure Sensor 19 Fuel Cooler7 EGR Valve 20 Supply Pump (HP3)8 EGR Cooler 21 Common-rail9 VSV (for EGR Cooler Bypass Valve) 22 Fuel Pressure Sensor10 Variable Nozzle Vane Turbocharger 23 Pressure Discharge Valve11 Camshaft Position Sensor 24 Differential Pressure Sensor12 Fuel Injector 25 Exhaust Temperature Sensor13 Exhaust Fuel Addition Injector 26 Air-fuel Ratio Sensor

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KD Series Engine31

Engine Specification[1[

Engine 1KD-FTV (*1) 2KD-FTV (*2) 1KD-FTV 2KD-FTV (*3) 1KD-FTV (*4)

Model KDJ9#KDJ12#

KDY2##KLH1#/2#KDN1##

KDH2#KLH1#/2#

KUN##

KDY2##KDH2#, KUN##

KDJ12#

Catalytic ConverterOxiadation Catalytic Converter

Oxiadation Catalytic Converter



Supply Pump HP2 HP3 HP3 HP3

Fuel Pressure

Pressurizing SCV X 2 SCV X 1 SCV X 1 SCV X 1

Depressurizing Pressure LimiterPressure Limiter


Pressure Limiter Pressure Discharge Valve

Max. Pressure 135MPa 135MPa 160MPa 160MPa180MPa

Fuel Pressure Sensor Single Element Single Element Single Element Twin Element

Fuel InjectorType Solenoid Solenoid Solenoid Solenoid

Compensation Resister Resister QR Code QR CodeExhaust Fuel Addition Injector Not Available Not Available Not Available Not Available

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2 Variation

System Diagram[2[ 1KD-FTV (*1) ■

ECM

EDU

1

2

3

45

678

9

10

11

1213

14

15

16

17

18

1921

20

1 Intake Air Temperature Sensor 12 Fuel Injector2 Air Flow Meter 13 Glow Plug3 Inter Cooler 14 Engine Coolant Temperature Sensor4 Intake Air Temperature Sensor 15 Crankshaft Position Sensor5 Diesel Throttle 16 Fuel Tank6 Manifold Absolute Pressure Sensor 17 Fuel Filter7 VSV (for Atmosphere Pressure Sensor) 18 Supply Pump (HP2)8 EGR Valve 19 Common Rail9 EGR Cooler 20 Fuel Pressure Sensor10 Variable Nozzle Vane Turbocharger 21 Pressure Limiter11 Camshaft Position Sensor

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2KD-FTV (*2) ■

ECM

EDU

1

2

3

4

5

6

78

922

10

11

12 13

14

15

16

17

18

19

21

20

1 Intake Air Temperature Sensor 12 Glow Plug2 Air Flow Meter 13 Engine Coolant Temperature Sensor3 Inter Cooler 14 Crankshaft Position Sensor4 Intake Air Temperature Sensor 15 Fuel Tank5 Diesel Throttle 16 Fuel Filter6 Manifold Absolute Pressure Sensor 17 Supply Pump (HP3)7 VSV (for Atmosphere Pressure Sensor) 18 Common Rail8 EGR Valve 19 Fuel Pressure Sensor9 Variable Nozzle Vane Turbocharger 20 Pressure Limiter10 Camshaft Position Sensor 21 Pressure Discharge Valve11 Fuel Injector 22 Exhaust Gas Control Valve

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2 Variation

1KD-FTV, 2KD-FTV (*3) ■

ECM

EDU

1

23

45

67

8

8

9

10

11

12

13

1415 16

17

18

19

21

22 24

23

20

1 Intake Air Temperature Sensor(Built-in Mass Air Flow Meter) 13 Camshaft Position Sensor

2 Air Flow Meter 14 Fuel Injector3 Intake Air Temperature Sensor 15 Glow Plug4 Inter Cooler 16 Engine Coolant Temperature Sensor5 Intake Air Temperature Sensor 17 Crankshaft Position Sensor6 Diesel Throttle 18 Fuel Tank7 Manifold Absolute Pressure Sensor 19 Fuel Filter8 EGR Valve 20 Fuel Cooler9 VSV (for Swirl Control Valve) 21 Supply Pump (HP3)10 EGR Cooler 22 Common Rail11 VSV (for EGR Cooler Bypass Valve) 23 Fuel Pressure Sensor12 Variable Nozzle Vane Turbocharger 24 Pressure Limiter

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1KD-FTV (*4) ■

ECM

EDU

1

2

3

4

5

6

7

8

9

10

11

12

1314 15

1617

18

19

21 2220

1 Intake Air Temperature Sensor 12 Camshaft Position Sensor2 Air Flow Meter 13 Fuel Injector3 Inter Cooler 14 Glow Plug4 Intake Air Temperature Sensor 15 Engine Coolant Temperature Sensor5 Diesel Throttle 16 Crankshaft Position Sensor6 Manifold Absolute Pressure Sensor 17 Fuel Tank7 EGR Valve 18 Fuel Filter8 VSV (for Swirl Control Valve) 19 Supply Pump (HP3)9 EGR Cooler 20 Common Rail10 VSV (for EGR Cooler Bypass Valve) 21 Fuel Pressure Sensor11 Variable Nozzle Vane Turbocharger 22 Pressure Discharge Valve

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2 Variation

VD Series Engine[1

Engine Specification[1[ Engine 1VD-FTV (*1) 1VD-FTV (*2)Model VDJ7# VDJ200

Catalytic Converter Oxidation Catalytic Converter Oxidation Catalytic ConverterSupply Pump HP4 HP4

Fuel Pressure

Pressurizing SCV X 1 SCV X 1Depressurizing Pressure Limiter Pressure Limiter

Max. Pressure 157MPa 175MPa (EURO 4)129MPa (Ohter than EURO 4)

Fuel Pressure Sensor Single Element Single Element

Fuel InjectorType Solenoid Solenoid

Compensation QR Code QR CodeExhaust Fuel Addition Injector Not Available Not Available

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System Diagram[2[ 1VD-FTV (*1) ■

ECM

EDU

1 2

3

4

5 5

6

7 7

88

9

10

11

11

12

12

1314

15

16 17

1819

19

21

20

1 Intake Air Temperature Sensor 12 Glow Plug2 Air Flow Meter 13 Engine Coolant Temperature Sensor3 Inter Cooler 14 Crankshaft Position Sensor4 Intake Air Temperature Sensor 15 Fuel Tank5 Diesel Throttle 16 Fuel Filter6 Manifold Absolute Pressure Sensor 17 Fuel Cooler7 EGR Valve 18 Supply Pump (HP4)8 EGR Cooler 19 Common Rail9 Variable Nozzle Vane Turbocharger 20 Fuel Pressure Sensor10 Camshaft Position Sensor 21 Pressure Limiter11 Fuel Injector

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2 Variation

1VD-FTV (*2) ■

ECM

EDU

12

3

4

5 5

6

7 7

88

99

10

11

11

1212

1314

15

16 17

1819

19

21

20

1 Intake Air Temperature Sensor 12 Glow Plug2 Air Flow Meter 13 Engine Coolant Temperature Sensor3 Inter Cooler 14 Crankshaft Position Sensor4 Intake Air Temperature Sensor 15 Fuel Tank5 Diesel Throttle 16 Fuel Filter6 Manifold Absolute Pressure Sensor 17 Fuel Cooler7 EGR Valve 18 Supply Pump (HP4)8 EGR Cooler 19 Common Rail9 Variable Nozzle Vane Turbocharger 20 Fuel Pressure Sensor10 Camshaft Position Sensor 21 Pressure Limiter11 Fuel Injector

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3 Main Components5

Supply Pump11

Outline[1[ The supply pump is a component that pressurizes fuel extremely high (up to 200 MPa) and feeds it to ●

the common-rail.Fuel is drawn from the fuel tank into the plunger chamber by the built-in feed pump through the ●

electromagnetic SCV (Suction Control Valve). The fuel in the plunger chamber, where the high-pressure is generated, is then fed to the common-rail by the plunger.The fuel, which is supplied to the exhaust fuel addition injector of a DPNR and DPF equipped engine*, ●

is not fed by the plunger, is supplied from the feed pump passing through the flow damper.Supply pumps are generally classified into two groups by the drive system of a plunger, inner cam ●

type (HP2), or outer cam type (HP3 and HP4).The ECM learns and memorizes the pump discharge volume variances associated with the individual ●

differences in the supply pumps.*: Except for the 1KD-FTV engine for Japan (as of October 2008).

Type

Inner Cam Outer CamHP2 HP3 HP4

Avensis and Land Cruiser etc.

Avensis and Land Cruiser etc.

Land Cruiser Station Wagon

Feed punp Vane Trochoid TrochoidSuction control valve 2 1 1

Plunger2 X 2 2 3

Driven by inner cam Tandem layout

Driven by outer cam Opposed layout

Driven by outer cam Opposed layout

Fuel intake regulating method

Regulating the SCV opening duration

Regulating the SCV opening angle

Regulating the SCV opening angle

Length* mm 250 190 190Weight* g 6000 3800 4900

* Reference value

The small displacement engines, which are used on the Yaris and Aygo, use the common-rail and a supply pump manufactured by Bosch (1ND-TV) or Siemens (2WZ-TV).　Similar to the Denso made HP4 supply pump, their supply pumps also regulate the fuel intake with the electromagnetic valve opening angle, and feed the pressurized fuel using the three opposed-layout plungers driven by the outer cam.

TIP

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3 Main Components

Inner Cam type Supply Pump (HP2 type)[2[

Construction<1< The inner cam type (HP2) supply pump consists of mainly a pump body (inner cam, roller, and four ●

plunger), two SCVs, a fuel temperature sensor and a feed pump. The four plungers are paired and are arranged in tandem. The paired plungers are arranged 180° away from each other.

Fuel Temp. Sensor

SCVs

OUT Regulator ValvePlunger (B) Inner Cam

Plunger (A)

SCV

RollerFeed Pump

IN

Supply Pump Fuel Circuit ■SCV

SCV

Delivery ValveCheck Valve

Check Valve

Regulator Valve

Feed Pump

Roller

Plunger (B)Roller

Inner Cam

Plunger (A)

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Operation<2<

General(1) The ECM controls the SCV opening duration in order to regulate the fuel volume that is pumped by ●

the supply pump to the common-rail. Consequently, the fuel pressure in the common-rail is regulated to the target injection pressure.

Suction Stroke(2) The plunger becomes positioned at the shorter diameter of the inner cam. When the inner cam rotates ●

from this position, the suction stroke starts as the plunger expands with the fuel pressure created by the feed pump.

Pump Chamber

SCVFuel

ONPlunger

PlungerRoller Inner Cam

Suction StartingSuction EndingInner Cam Rotation Direction

Pumping Stroke(3) The plunger becomes positioned at the longer diameter of the inner cam. When the inner cam rotates ●

from this position, the pumping stroke starts as the plunger is pushed by the inner cam.

Plunger

SCV

Fuel

Fuel

OFF

Suction Starting Suction EndingInner Cam Rotation Direction

Pump Chamber

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3 Main Components

Outer Cam type Supply Pump (HP3 and HP[ type)[3[

Construction<1<

HP3 type(1) The outer cam type (HP3 type) supply pump consists of an eccentric cam shaft, a ring cam, two ●

plungers, four check valves, an SCV, a fuel temperature sensor, and a feed pump. The two plungers are placed opposite each other outside of the ring cam.

Plunger

Plunger Ring Cam

Pump

Plunger

Fuel Temp.Sensor

EccentricCam

SCV

Supply Pump Fuel Circuit ■

Ring Cam

PlungerA

PlungerB

Check Valve

EccentricCam

SCV

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HP[ type(2) The outer cam type (HP4 type) supply pump consists of an eccentric camshaft, ring cam (polygon ●

ring), and three plungers, an SCV, and a feed pump. Each plunger is placed outside of the ring cam.

Inner Cam

Outer Cam

Plunger

Feed Pump

Feed Pump

SCV

Supply Pump Fuel Circuit ■

Suction

Inner Cam

Outer Cam

Plunger A

Plunger C

Plunger B

To InjectorSCV

Operation<2<

General(1) The ECM controls the opening of the SCV in order to regulate the volume of fuel that is pumped by ●

the supply pump to the common-rail. Consequently, the fuel pressure in the common-rail is controlled to the target injection pressure.

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3 Main Components

SCV Opening Small(2) When the opening of the SCV is small, the fuel suction area is kept small, which decreases the ●

transferable fuel quantity.If the plunger strokes fully, however, the suction volume becomes small due to the small suction area. ●

Therefore, the difference of the volume between the geometry volume and the suction volume is in the vacuum condition.Pumping will start at the time when the fuel pressure has become higher than the common-rail ●

pressure.

SCV

Fuel Pumping Mass

Cam Stroke

Small Suction Area

Plunger BDCPlunger TDCPumping Starting Point

SCV Opening Large(3) When the opening of the SCV is large, the fuel suction area is kept large, which increases the ●

transferable fuel quantity.If the plunger strokes fully, the suction volume will increase because the suction area is large. ●

Pumping will start when the fuel pressure has become higher than the common-rail pressure. ●

SCV

Fuel Pumping Mass

Cam Stroke

Large Suction Area

Pumping Starting Point

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Flow Damper[[[ The flow damper is provided in the fuel supply path (the rear end of the feed pump) connected to the ●

exhaust fuel addition injector, and incorporates a piston and a spring. The piston is operated by the fuel pressure, and opens and closes the fuel supply path.The fuel pumped by the feed pump is supplied to the exhaust fuel addition injector flowing through ●

the flow damper. The built-in spring dampens the pulses that occur when the fuel is supplied. Furthermore, if the fuel is pressurized abnormally high, that fuel pressure will overcome the spring force, and as a result, the fuel supply path will be closed by the piston, shutting off the fuel to the exhaust fuel addition injector.

Feed Pump

To Exhaust fuel addition Injector

Piston

Flow Damper

Flow DamperSupply Pump Orifice

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3 Main Components

Common-rail21 The function of the common-rail is to store the fuel that has been pressurized by the supply pump. ●

Internally, the common-rail contains a main hole and five branch holes that intersect the main hole. ●

Each branch hole functions as an orifice that dampens the fluctuation of the fuel pressure.The common-rail incorporates either a pressure limiter (mechanical valve) or pressure discharge ●

valve (electromagnetic valve), and a fuel pressure sensor.The pressure limiter is a mechanical valve that consists of a spring and a valve, and if the common- ●

rail internal fuel pressure rises abnormally high, it opens the valve to discharge the pressure.The pressure discharge valve is an electromagnetic valve that consists of a solenoid coil, a return ●

spring, and a plunger. In the pressure discharge valve, the plunger opens and closes in accordance with the actuation signals from the EDU. Thus, it regulates pressure by releasing excess pressure from the common-rail. In addition, it has a pressure reduction function in case of emergency.The regulating method for the target common-rail pressure varies depending on the fuel pressure ●

control valves.

Target Common-railPressure Control

OutlinePressureDischarge

Valve

PressureLimiter

Fuel Pressure Sensor

Pressurizing The SCV pressurizes the fuel to the target value. - ○ Single

Pressurizing and depressurizing

The SCV pressurizes the fuel to the target value and the pressure discharge valve depressurizes the fuel when necessary.

○ -* Double

* Some engines are equipped with both a pressure discharge valve and pressure limiter.

The fuel pressure sensor has its sealing portion plastic-deformed in order to maintain the sealing ●

performance, so do not reuse it after disassembling.The fuel pressure sensor and pressure discharge valve are supplied as a set with the common-rail. ●

Do not disassemble the fuel pressure sensor and pressure discharge valve. ●

If parts that affect the alignment have been changed, make sure to replace the pipe (Injection Pipe, ●

Fuel Inlet Pipe) with a new one. For details, refer to the Repair Manual. ●

POINT

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Common-rail with Pressure Discharge Valve ■

To Fuel Tank


Pressure Limiter

Branch Hole


Common-rail

Valve Open

Valve Open

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3 Main Components

Injector31

Outline[1[ There are 2 types of injectors; the fuel injector that injects fuel into the combustion chamber and the ●

exhaust fuel addition injector that injects fuel into the exhaust port.The fuel injectors atomize the high-pressure fuel accumulated in the common-rail and inject it to the ●

combustion chamber at the optimum injection timing, injection counts and injection rate in accordance with the ECM signals. The injectors can be divided into 2 types; the solenoid type and piezo type in accordance with the valve opening types.The exhaust fuel addition injectors inject the fuel into the exhaust port to raise the catalyst temperature ●

and conduct the exhaust emission after-treatment. They are provided on the engines with DPNR or DPF.The fuel injectors have unique injection characteristics and the characteristics should be equalized ●

to improve the injection accuracy of the common-rail system. The equalization can be performed by using the compensation resistance or injector compensation value.*: Except for the 1KD-FTV engine for Japan (as of Ocotber 2008).

Type

Fuel Injector Exhaust FuelAddition Injector

Solenoid Type Piezo Type Solenoid TypeAvensis and

Land Cruiser etc. Avensis with 2AD-FHV Avensis with DPNR and DPF

Valve opening control method

Nozzle needle is opened indirectly using control

chamber pressure control using solenoid valve (2-way

valve)

Nozzle needle is opened indirectly using control

chamber pressure control using 3-way valve driven by

piezo actuator

Nozzle needle is opened by directly driving it with

solenoid valve

Number of injection holes

5 to 8(The number changes in

accordance with the engine types)

1

Injection hole diameter mm 0.14 to 0.15 Slit

Injection characteristics compensation

Compensation resistanceInjector Compensation Value

(QR Code) -Injector compensation value(QR Code)

Corresponding injection counts 3 5 -

Maximum injection pressure MPa 180 200 1

0493ono

テキストボックス

10

0493ono

テキストボックス

0.128 to 0.134

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Solenoid type Fuel Injector[2[

Construction<1< The solenoid type fuel injector is composed of the nozzle needle, piston that controls the nozzle ●

needle, control chamber with inflow and outflow orifice, and solenoid valve (2-way Valve) that controls inflow and outflow of the fluid into the control chamber.

Nozzle Needle

Piston

Solenoid Valve

Operations<2< When electrical current is applied to the solenoid coil, it pulls the solenoid valve up. ●

The orifice to the control chamber opens, allowing the fuel to flow out. ●

The fuel pressure in the control chamber drops. ●

Simultaneously, fuel flows from the orifice to the bottom of the piston and raises the piston up (to ●

enhance response).As a result, the piston raises the nozzle needle to inject fuel. ●

Solenoid Coil

Piston

Solenoid Valve

Control Chamber

Fuel Fuel

Nozzle Needle

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3 Main Components

Piezo type Fuel Injector[3[

Construction<1< The piezo type fuel injector is composed of the nozzle needle, 2 pistons that control the nozzle ●

needle, 3-way valve, control chamber with inflow and outflow orifice, and piezo actuator that controls inflow and outflow of the fluid into the control chamber.The piezo actuator has an increased responsiveness than the aforementioned solenoid valve, thus ●

using it contributes to achieving a higher needle valve opening speed, improved injection accuracy under extremely high pressure, improved fuel atomization, multiple injection correspondence and more.The EDU regulates the injector to decrease the injector operation voltage and speed upon receiving ●

a signal, that indicates idling conditions, from the ECM in order to reduce the injector operation noise while idling.

Nozzle Needle

No.1 Piston

Three-Way Valve

Piezo Actuator

No.2 Piston

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Operations<2<

During Injection(1) The piezo actuator is electrically charged when current is applied to it, causing the No.1 piston, No.2 ●

piston and the three-way valve to be pushed down.The orifice on the upper part of the three-way valve opens and the fuel in the control chamber flows ●

out.The fuel pressure in the control chamber drops. ●

As a result, the nozzle needle is pushed up due to fuel pressure, causing fuel injection. ●

While Stopped(2) When current is no longer applied to the piezo actuator, it loses its electrical charge, causing the No.1 ●

piston, No.2 piston and the three-way valve to be pushed up due to spring tension.The orifice on the upper part of the three-way valve closes to stop fuel flow. ●

The fuel pressure in the control chamber rises. ●

As a result, the nozzle needle goes down, stopping fuel injection. ●

Piezo Actuator FuelFuel

To Fuel Tank

Control Chamber

No.1 Piston

Nozzle Needle

No.2 Piston

Three-Way Valve

While Stopped During Injection

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3 Main Components

Exhaust Fuel Addition Injector[[[ An exhaust fuel addition injector is installed on the No. 4 exhaust port of the cylinder head. This ●

injector supplies additional fuel into the No. 4 exhaust port for the purpose of realizing exhaust fuel enrichment (in order to reduce NOx), to help create and maintain the proper catalyst temperature for the purpose of PM recovery and sulfur poison recovery (only for the engines with DPNR).The exhaust fuel addition injector is composed of a needle valve body with a slit shaped injection ●

hole and a solenoid coil that drives the needle valve, and injects the fuel in the fan shaped pattern as shown.

Solenoid Coil

Slit Shaped Injection Hole

Needle Valve View from A

Needle Valve Body

A

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Catalytic Converter[1

Outline[1[ The catalytic converter is an exhaust gas after-treatment system that removes harmful substances ●

such as CO, HC, NOx and PM in exhaust emissions, conducts storage and reduction of NOx and trapping and recovery of PM.For diesel engines, the oxidation catalyst that purifies CO and HC is generally used, and for some ●

engines, the DPF catalyst, NSR catalyst or DPNR catalyst that can purify PM and NOx is used.

Purifying Methods and Purified Pollutants

Diesel Gasoline

Oxidation Catalyst

DPF DPNR3-way

CatalystDPF Catalyst

NSR Catalyst

DPNR Catalyst

OxidationCO ○ ○ ○ ○ ○HC ○ ○ ○ ○ ○

ReductionNOx

- - ○ ○ ○Storage - - ○ ○ -Trapping

PM- ○ - ○ -

Recovery - ○ - ○ -

Oxidation Catalyst[2[ The oxidation catalyst is a catalytic converter that purifies CO and HC in the exhaust emissions, ●

converting them to CO2 and HC by oxidation. The catalyst is only active when there is enough oxygen.

Oxidation Catalytic Converter CO + O2 = CO2

HC + O2 = CO2 + H2O

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DPF[3[ The DPF catalyst is a catalytic converter with an oxidation catalyst supported by a porous ceramic ●

structure. The porous ceramic structure traps PM and the oxidation catalyst purifies CO and HC. Trapped PM is catalytically oxidized under the high catalyst temperature conditions.

Filter

Oxidation Catalyst

Exhaust Gas

DPF Catalyst

DPNR[[[ The NSR catalyst and DPNR catalyst integrated catalytic converter is used for the DPNR. ●

The NSR catalyst purifies NOx by storage and reduction of NOx and it is composed by the ceramic ●

structure and the attached NOx storage layer.The DPNR catalyst traps PM by the porous ceramic structure and purifies NOx by storage and ●

reduction of NOx using the NOx storage layer attached to the structure.NOx is stored under lean air/fuel ratio conditions, released from the catalyst and then reduced to N ● 2

under rich air/fuel ratio conditions. PM is oxidized under low temperature condition by active oxygen released from the catalyst at the time NOx is stored or released.

NOx

NOx

NOx

NOx

NSR Catalyst

PM

PM

NOx Storage Layers

NOx Storage Layers

NOx Storage Layers

Exhaust GasExhaust Gas

Pt

Pt

Pt

S

DPNR Catalyst

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[ Sensors6

Mass Air Flow Meter11

Description[1[ The mass air flow meter measures the intake air amount via a platinum hot wire (heater) by passing ●

air through the sensor.When the intake air amount changes, the bridge circuit for the platinum hot wire (heater) regulates the ●

current flowing through the hot wire (heater) according to the feedback control in order to maintain the temperature difference between the temperature sensor and the hot wire (heater) at a constant level. The current flowing through the hot wire (heater) is converted into voltage, and then output to the ECM. The ECM calculates the air intake of an engine based on the predetermined relationship between the output voltage and voltage flow of the mass air flow meter.The ECM uses the output value from the mass air flow meter in the fuel injection volume control and ●

the EGR control.The air flow meter has a built-in atmospheric temperature sensor. ●

Temperature Sensing Element

Hot-Wire Element

Air Flow

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Circuit[2[

Mass Air Flow Meter Circuit<1<

Platinum Hot Wire

ADC

12 V

VG

EVG

E1

Output Circuit

Microprocessor

Mass Air Flow Meter ECM

Temperature Sensor

Terminal Voltage<2<

Problem Condition

Terminal Voltage

Value on Data List (MAF)

+BSensor power

source (Sensor terminal)

VGSensor output (ECM

terminal)

EVGSensor ground (ECM

terminal)

Normal (IG ON) Same as battery voltage Depends on 0 V Depends on

+B open Below 1.5 V 0 V 0 V 0.5 g/sec less

VG open Same as battery voltage 0 V 0 V 0.5 g/sec less

VG short Same as battery voltage 0 V 0 V 0.5 g/sec less

EVG open Same as battery voltage 9 V or more 0 V 200 g/sec over

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Character[3[

Volta

ge (V

)

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0.50.0

0 20 40 60 80 100 120 140 160 180Flow rate (g/sec)

On new Avensis AD series engines, the output voltage is converted into output frequency by a frequency conversion circuit inside the mass air flow meter and transmitted to the ECM. By converting the mass air flow meter output into frequency (frequency range between 250 to 11,000 Hz), a more accurate intake air amount value can be gained because the value is then less likely to be affected by the differences between resistance of the individual circuits including the wire harnesses.

Out

put f

requ

ency

(Hz)

Intake air flow amount (g/s)

10000

01 1000

TIP

Related Engine Control[[[ Controls in which the sensor is used

Fuel Injection Volume ControlEGR Control

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Manifold Absolute Pressure Sensor (Turbo Pressure Sensor)21

Description[1[ The manifold absolute pressure sensor, which outputs changes in the pressure applied to the built-in ●

silicon chip as electric signals, detects the intake manifold pressure.As 5 V from the ECM constant-voltage power supply circuit is applied to the sensor, the silicon chip ●

resistance value varies with the changes in the intake manifold pressure. The resistance is output to the ECM after being converted to voltage by the IC built into the sensor. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The manifold absolute pressure sensor detects the absolute pressure, thus the value does not change ●

depending on the climate or place.The ECM uses the value output from the manifold absolute pressure sensor for the fuel injection ●

volume control and fuel injection timing control.

Sensor Unit

Circuit[2[

Manifold Absolute Pressure Sensor Circuit<1<

Manifold AbsolutePressure Sensor

5V Constant Voltage Circuit

ADC

Microprocessor

ECM

IC

VCPM

PIM

EPIM

E1Silicon Chip

Intake Manifold Pressure

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Terminal Voltage<2<

Problem Condition

ECM Terminal Voltage

Value on Data List (MAP)VCPM Sensor power

source

PIM Sensor output

EPIM Sensor ground

Normal (IG ON) 5 V Depends on 0 V Same value as the actual atmospheric pressure

VCPM open 5 V 0.5 V or less 0 V 40 kPa or more or less

VCPM short 0 V 0 V 0 V No communication with ECM (ECM processor down)

PIM open 5 V 5 V 0 V 250 kPa or morePIM short 5 V 0 V 0 V 30 kPa or less

EPIM open 5 V 5 V 0 V 250 kPa or more

Character[3[ 5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.00 40 80 120 160 200 240 280 320

Volta

ge (V

)

Pressure (kPa)


Fuel Injection Volume ControlFuel Injection Timing ControlEGR Control

Intelligent Tester usage

The manifold absolute pressure sensor output can be checked easily by the data list functions of ●

the intelligent tester. When the manifold absolute pressure and the atmospheric pressure values are nearly the same with the ignition switch in the on position and the engine stopped, it can be determined that the manifold absolute pressure sensor and the atmospheric pressure sensor work normally. If there is a difference of 8 kPa or more, compare the values to the atmospheric pressure for that day. The sensor whose deviation is the greatest is malfunctioning.Standard atmospheric pressure is 101 kPa. For every 100 m increase in altitude, pressure drops by 1 ●

kPa. Varies by weather.

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Engine Coolant Temperature Sensor31

Description[1[ The engine coolant temperature sensor has a built-in thermistor that changes its resistance value ●

corresponding to the temperature in order to detect the engine coolant temperature. The lower the coolant temperature is, the more the thermistor resistance value increases. Similarly, the higher the coolant temperature is, the more the thermistor resistance value decreases.As 5 V from the ECM constant-voltage power supply circuit is applied through the resistance R to the ●

sensor, the voltage of the signal terminal varies with the changes in the resistance value of the sensor. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The ECM uses the value output from the engine coolant temperature sensor for the fuel injection ●

volume control, fuel injection timing control and cooling fan control.

Thermistor

Radiator coolant temperature sensor ■The radiator coolant temperature sensor detects the engine coolant temperature around the radiator. ●

The sensor structure, operation and wire connection to the ECM are the same as those of the sensor attached to the engine. The output signal of the sensor is mainly used for drive control of the cooling fan, and the ECM controls the cooling fan motor in accordance with the coolant temperature around the radiator.The ECM terminal voltage (RTHW, E2) in the radiator coolant temperature sensor circuit and the data ●

displayed on the Data List (Radiator Coolant Temp.) have the almost same characteristics as those of the engine coolant temperature sensor.In a vehicle equipped with the radiator coolant temperature sensor, the cooling fan motor is controlled ●

in accordance with the signal output from the radiator coolant temperature. Therefore, it is not affected by the signal output from the engine coolant temperature sensor.

TIP

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Circuit[2[

Engine Coolant Temperature Sensor Circuit<1<


ADC

Microprocessor

ECM

R

THW

ETHW

E1Engine Coolant Temperature Sensor

Terminal Voltage<2<

Problem ConditionECM Terminal Voltage

Value on Data List(Coolant Temp)THW

Sensor outputETHW

Sensor groundNormal (IG ON) Depends ON 0 V Depends ON

THW open 5 V 0 V -40 ˚CTHW short 0 V 0 V 140 ˚CE2 open 5 V 0 V -40 ˚C

Character[3[ 5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

Volta

ge (V

)

Temperature (˚C)

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Fuel Injection Volume ControlFuel Injection Timing ControlCooling Fan Control (Only for vehicle with ECM controlled electric cooling fan)


The engine coolant temperature sensor output can be checked easily by the data list functions of ●

the intelligent tester. After a long soak, the fuel temperature, the intake air temperature and the engine coolant temperature become approximately equal to the actual ambient temperature. From this characteristic, when the value displayed on the data list is very different from the actual ambient temperature, there may be a malfunction in the system circuit.

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Intake Air Temperature Sensor[1

Description[1[ The intake air temperature sensor has a built- in thermistor that changes resistance value ●

corresponding to the temperature to detect the intake air temperature. The lower the intake air temperature is, the higher the thermistor resistance becomes, and the higher the intake air temperature is, the lower the thermistor resistance becomes.There are three types of intake air temperature sensors; the first one has a built-in mass air flow meter ●

and detects the temperature of the intake air around the engine air inlet port, the second one has no built-in sensor and detects the intake air temperature around the engine air inlet port, and the last one has also no built-in sensor but is fitted behind the turbocharger (intercooler).As 5 V from the ECM constant-voltage power supply circuit is applied through the resistance R to the ●

sensor, the voltage of the signal terminal varies with the changes in the resistance value of the sensor. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The ECM uses the value output from the intake air temperature sensor for the fuel injection volume ●

control, fuel injection timing control and EGR control.

Intake Air Temperature Sensor(Built-in Mass Air Flow Meter)

Intake Air Temperature Sensor Intake Air Temperature Sensor

Thermistor

Thermistor

Air Filter

Intercooler

Turbo charger

Thermistor

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Circuit[2[

Intake Air Temperature Sensor Circuit<1<


ADC Microprocessor

ECM

ETHI

THA

ETHA

THIA

E1

Intake Air Temperature Sensor (Air Inlet Port)

Intake Air Temperature Sensor (Behind-Turbocharger)

Terminal Voltage<2< Intake air temperature around air inlet port ■Problem Condition

ECM Terminal Voltage Value on Data List(Intake Air)

(Intake Air Temp (turbo))THA

Sensor outputETHA


THA open 5 V 0 V -40 ˚CTHA short 0 V 0 V 140 ˚C

ETHA open 5 V 0 V -40 ˚C

Intake air temperature behind turbocharger ■Problem Condition

ECM Terminal Voltage Value on Data List(Intake Air)

(Intake Air Temp (turbo))THIA

Sensor outputETHI


THIA open 5 V 0 V -40 ˚CTHIA short 0 V 0 V 140 ˚C or moreETHI open 5 V 0 V -40 ˚C

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Character[3[ 5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

Volta

ge (V

)

Temperature (˚C)




The intake air temperature sensor output can be checked easily by the data list functions of the ●

intelligent tester. After a long soak, the fuel temperature, the intake air temperature and the engine coolant temperature become approximately equal to the actual ambient temperature. From this characteristic, when the value displayed on the data list is very different from the actual ambient temperature, there may be a malfunction in the system circuit.

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Fuel Temperature Sensor51

Description[1[ The fuel temperature sensor has a built-in thermistor that changes its resistance value corresponding ●

to the temperature in order to detect the fuel temperature. The lower the fuel temperature is, the more the thermistor resistance value increases. Similarly, the higher the fuel temperature is, the more the thermistor resistance value decreases.As 5 V from the ECM constant-voltage power supply circuit is applied through the resistance R to the ●

sensor, the voltage of the signal terminal varies with the changes in the resistance value of the sensor. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The ECM uses the value output from the fuel temperature sensor for the fuel injection volume control, ●

fuel injection timing control and fuel pressure control.

Fuel Temperature Sensor

Thermistor

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Circuit[2[

Fuel Temperature Sensor Circuit<1<


ADC

Microprocessor

ECM

THF

ETHF

E1Fuel Temperature Sensor

Terminal Voltage<2<


Value on Data List(Fuel Temp)THF

Sensor outputETHF


THF open 5 V 0 V -40 ˚CTHF short 0 V 0 V 140 ˚C

ETHF open 5 V 0 V -40 ˚C

Character[3[ 5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

Volta

ge (V

)

Temperature (˚C)

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Fuel Injection Volume ControlFuel Injection Timing ControlFuel Pressure Control


The fuel temperature sensor output can be checked easily by the data list functions of the intelligent ●

tester. After a long soak, the fuel temperature, the intake air temperature and the engine coolant temperature become approximately equal to the actual ambient temperature. From this characteristic, when the value displayed on the data list is very different from the actual ambient temperature, there may be a malfunction in the system circuit.

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Atmosphere Pressure Sensor61

Description[1[ The atmosphere pressure sensor, which outputs changes in the pressure applied to the built-in silicon ●

chip as electric signals, detects the atmospheric pressure.There are 2 types of atmosphere pressure sensors; an ECM built-in type and a combination type ●

that measures the intake manifold pressure and atmospheric pressure separately using the manifold absolute pressure sensor (turbo pressure sensor).5 V from the ECM constant-voltage power supply circuit is applied to the sensor, and the silicon ●

chip resistance varies with the change in the atmospheric pressure. The resistance is output to the ECM after being converted to voltage by the IC built into the sensor. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The ECM uses the value output from the atmosphere pressure sensor for the fuel injection volume ●

control, fuel injection timing control and EGR control.

Atmosphere Pressure Sensor(ECM Built-in Type)

Atmosphere Pressure Sensor(Combination Type)

Sensor Unit

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Circuit[2[

Atmosphere Pressure Sensor Circuit<1< ECM built-in Type ■

ADC


IC

Microprocessor

Atmosphere Pressure Sensor

ECM

Silicon Chip

Combination Type ■5V Constant Voltage

Circuit

ADCADC

DriveCircuit

MicroprocessorManifold Absolute Pressure Sensor

Battery

MAINVSV

ECM

VC

PIM

E2

PA

12 V

MREL

E1

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Terminal Voltage (Combination type)<2<

Problem Condition

ECM Terminal Voltage

Value on Data ListVCSensor power

source

PIMSensor output

E2Sensor ground

Normal (IG ON) 5 V Depends on 0 V Same value as the actual atmospheric pressure

VC open 5 V 5 V 0 V 250 kPa or more

VC short 0 V 0 V 0 V No communication with ECM (ECM Processor down)

PIM open 5 V 5 V 0 V 250 kPa or morePIM short 5 V 0 V 0 V 0 kPaE2 open 5 V 5 V 5 V 250 kPa or more

Perform the inspection using DTCs or the data list functions of the intelligent tester as the ECM built-in type cannot measure the terminal voltage.

TIP

Character[3[ 5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.00 40 80 120 160 200 240 280

Volta

ge (V

)

Pressure (kPa)

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Measurement switch conditions of the combination typeAmbient pressure measurement conditions:

(1) 0 rpm engine speed(2) Starter ON(3) Stable engine idling

(Measures the atmospheric pressure for a predetermined time when one of the above conditions is met.)

Intake manifold pressureMeasurement conditions-(Measures the intake manifold pressure when none of the above measurement conditions are met.)

TIP




ECM built-in type atmospheric pressure sensor output can be checked easily by the data list ●

functions of the intelligent tester. When the manifold absolute pressure and the atmospheric pressure values are nearly the same with the ignition switch in the on position and the engine stopped, it can be determined that the manifold absolute pressure sensor and the atmospheric pressure sensor work normally. If there is a difference of 8 kPa or more, compare the values to the atmospheric pressure for that day. The sensor whose deviation is the greatest is malfunctioning.Standard atmospheric pressure is 101 kPa. For every 100 m increase in altitude, pressure drops by 1 ●

kPa. Varies by weather.

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TOPICS Relationship between Atmospheric Pressure and Altitude

In our daily lives, we do not feel the weight of air. However, since it is “mass”, air has weight.A mass volume of air weighs about 1 kg per 1 cm2 around sea level. This is called atmospheric pressure. Namely, “atmospheric pressure = the pressure caused by the weight of air”.

The standard unit of atmospheric pressure is “hPa* (hectopascal)”, and the standard atmospheric pressure (1 atmospheric pressure) equals 1013.25 hPa.If translated into a unit available on the intelligent tester, it is about 101 kPa.

* 1hPa = 100Pa =0.1 kPa

Next, we will talk about the relationship between atmospheric pressure and altitude.As explained above, atmospheric pressure is the weight of air. This may prompt you to think: “If we go up to a higher location, we have less air pushing down from above, and therefore the atmospheric pressure becomes lower.That’s right. As illustrated below, the higher in altitude we go, the lower the atmospheric pressure we have.At up to an altitude of 3000 m, atmospheric pressure decreases by 1 kPa / 0.145 psi (0.01 atmospheric pressure) every 100 m higher we go.

Relationship between Altitude and Atmospheric Pressure

5000 m(55 kPa)

3000 m(70 kPa)

0.5 atmospheric pressure

0.7 atmospheric pressure

1 atmospheric pressure0 m

(101 kPa)

120

10190

8070

62

55

100

80

60

40

20

00 1000 2000 3000 4000 5000

Atm

osph

eric

Pre

ssur

e (k

Pa)

Altitude (m)

Relationship between Altitude Atmospheric Pressure

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Fuel Pressure Sensor71

Description[1[ The fuel pressure sensor, which outputs changes in the pressure applied to the built-in silicon chip as ●

electric signals, detects the fuel pressure in the common-rail.Fuel pressure sensors can be classified into 2 different types; a single element type that has one ●

sensor circuit and a twin element type that has 2 sensor circuits.As 5 V from the ECM constant-voltage power supply circuit is applied to the sensor, the silicon chip ●

resistance value varies with the changes in the fuel pressure. This resistance value is output to the ECM after being converted to voltage by the IC built in the sensor. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The ECM uses the value output from the fuel pressure sensor for the fuel injection volume control and ●

fuel pressure control.

Single Element Type

Twin Element Type


The twin element type sensor, which has higher reliability compared to the single element type, is provided on common rails which are not equipped with the pressure limiter. (The higher output control value is used.)

TIP

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Circuit[2[

Fuel Pressure Sensor Circuit<1< Single Element Type ■

ADC


IC

VC

PCR

E2

E1Microprocessor


ECM

Twin Element Type ■

ADC


IC

IC

VCM

PCR1E2M

VCS

PCR2

E2S

E1

Microprocessor

Fuel Pressure Sensor ECM

Terminal Voltage<2<

Single element type ■Problem Condition

ECM Terminal VoltageValue on Data List

(Fuel Press)VC

Sensor power source

PCRSensor output

E2Sensor ground

Normal (IG ON) 5 V Depends on 0 V Same value as the actual fuel pressure

VC open 5 V 5 V 0 V 200000 kPa or more

VC short 0 V 0 V 0 V No communication with ECM (ECM processor down)

PCR open 5 V 5 V 0 V 200000 kPa or morePCR short 5 V 0 V 0 V 0 kPaE2 open 5 V 5 V 5 V 200000 kPa or more

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Twin element type (PCR1 system) ■Problem Condition


(Fuel Press)VCM

Sensor power source

PCR1Sensor output

E2MSensor ground


VCM open 5 V 0 V 0 V No communication with ECM (ECM processor down)

VCM short 0 V 0 V 0 V No communication with ECM (ECM processor down)

PCR1 open 5 V 5 V 0 V 200000 kPa or morePCR1 short 5 V 0 V 0 V 0 kPaE2M open 5 V 5 V 0 V 200000 kPa or more

Twin element type (PCR2 system) ■Problem Condition


(Common Rail Press Sens 2)VCS

Sensor power source

PCR2Sensor output

E2SSensor ground


VCS open 5 V 0 V 0 V No communication with ECM (ECM processor down)

VCS short 0 V 0 V 0 V No communication with ECM (ECM processor down)

PCR2 open 5 V 5 V 0 V 200000 kPa or morePCR2 short 5 V 0 V 0 V 0 kPaE2S open 5 V 5 V 0 V 200000 kPa or more

When there are any problems in either of the PCR1 or the PCR2 system fuel pressure signal circuit, the ECM controls the engine using the fuel signal which has no errors. When any signal error is detected in the single element type fuel pressure sensor, the normal value before error detection (fixed value) will be used to continue the control.

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Character[3[ Single element type ■

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.00 30 60 90 120 150 180 210

Volta

ge (V

)

Pressure (MPa)

Twin element type ■

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.00 30

MainSub

60 90 120 150 180 210

Volta

ge (V

)

Pressure (kPa)


Fuel Injection Volume ControlFuel Pressure Control

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4 Sensors

Crankshaft Position Sensor81

Description[1[ The crankshaft position sensor has a built-in pick-up coil and generates a pulse when the timing rotor ●

which is attached to the crankshaft rotates and passes through the sensor.The air gap between the projecting portions on the timing rotor and the crankshaft position sensor ●

varies upon the rotation of the timing rotor. This increases and decreases the magnetic flux passing through the pick-up coil, generating the electromotive force on the coil. The generated voltage flows in one direction when the projecting portions on the timing rotor come close to the crankshaft position sensor, whereas it flows in the opposite direction when the projecting portions on the timing rotor come away from the coil. The generated pulses are converted into rectangular waves by the input circuit in the ECM, thus generating the AC voltage.The timing rotor has 34 teeth (arranged at 10 degree intervals) and 2 of them are chipped. ●

The ECM detects the crankshaft angle (top dead center point), cylinder number and engine speed in ●

accordance with the pulse (Ne signal) from the crankshaft position sensor and the pulse (G signal) from the camshaft position sensor.

720 ˚CA

G Signal

2 Teeth Missing

Crankshaft Position Sensor

Ne Signal

360 ˚CA

34 Pulse/360 ˚CA

34 Pulse/360 ˚CA

Timing Rotor34 Pulse/360 ˚CA

360 ˚CA

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Circuit[2[

Crankshaft Position Sensor Circuit<1<

NE+

NE- Microprocessor

Waveform Shaping IC


Timing Rotor

ECM

Terminal Voltage<2< When the engine starts. When the engine stops.

Ne + Open (Short) Ne - Open

Open Open

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Character[3[ The ECM input circuit converts changes in the sensor electromotive force into rectangular waves ●

and input them into the microprocessor, with the predetermined standard voltage (trigger level) set as the switching start point. Therefore, the ECM judges that the engine speed is 0rpm when the electromotive force (sensor output pulse) does not reach the standard voltage.

Reference Voltage

10 ˚CA

51 15 3010 2520 34

360 ˚CA

Converted Rectangular Wave

Low to Mid rpm Mid to High rpm

Reference Voltage approx. 30 mV approx. 30 mV


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Camshaft Position Sensor91

Description[1[ The crankshaft position sensor has a built-in pick-up coil and generates a pulse when the timing ●

sprocket/timing pulley rotates and passes through the camshaft position sensor.The air gap between the projecting portions on the outer circumference of the camshaft timing ●

sprocket/timing pulley and the camshaft position sensor varies when the camshaft timing sprocket/timing pulley rotates. This increases and decreases the magnetic flux passing through the pick-up coil, generating the electromotive force on the coil. The generated voltage flows in one direction when the projecting portions come close to the pick-up coil, whereas it flows in the opposite direction when the projecting portions come away from the coil, thus generating the AC voltage. The generated pulses are converted into rectangular waves by the input circuit in the ECM.There are 2 types of projecting portions arranged on the outer circumference of the timing sprocket ●

and the timing pulley: 1-tooth type and 5-teeth type.The ECM detects the crankshaft angle (upper dead center point) and cylinder number in accordance ●

with the pulse (G signal) from the camshaft positioning sensor and the pulse (Ne signal) from the crankshaft position sensor.

1-Tooth Type

Camshaft Position Sensor

Camshaft Position Sensor

G Signal(1-Tooth Type)

G Signal(5-Teeth Type)

Ne Signal

1 Pulse/720 ˚CA

1 Pulse/720 ˚CA

180 ˚CA

360 ˚CA 360 ˚CA

720 ˚CA

180 ˚CA 180 ˚CA

5 Pulse/720 ˚CA

180 ˚CA 180 ˚CA 180 ˚CA

5 Pulse/720 ˚CA

5-Teeth Type

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Circuit[2[

Camshaft Position Sensor Circuit<1<

G+

G- Microprocessor

Waveform Shaping IC


Timing Rotor

Timing Rotor

1-Tooth

5-Teeth

ECM

Terminal Voltage<2< G+ Open (Short) G- Open

Open Open

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Character[3[ The ECM input circuit converts the changes in the sensor electromotive force into rectangular waves ●

and inputs them into the microprocessor, with the predetermined standard voltage (trigger level) set as a switching start point. Therefore, the ECM judges that the camshaft is not rotating if the sensor electromotive force (sensor output pulse) does not reach the standard voltage value.

1-Tooth Type

5-Teeth Type

720 ˚CA

720 ˚CA

180 ˚CA 180 ˚CA 180 ˚CA

Reference Voltage

Converted Rectangular Wave

Low to Mid rpm Mid to High rpm

Reference Voltage approx. 300 mV approx. 650 mV


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Accelerator Pedal Position Sensor111

Description[1[ The accelerator pedal position sensor detects the accelerator pedal opening degree using the hall IC, ●

which can retrieve the magnetic field strength as electric signals using the hall effect.As 5 V from the ECM constant-voltage power supply circuit is applied to the sensor, the magnetic field ●

angle for the applied current flow inside the hall IC varies in accordance with the accelerator pedal depression amount, therefore, the applied current and the vertical magnetic field strength vary. Thus, the changes in the voltage generated perpendicular to the applied current and the magnetic field are sent to the ECM as accelerator pedal depression amount signals.The accelerator pedal position sensor has 2 types of circuits with different characteristics, and the ●

ECM detects the actual degree of the accelerator pedal and the accelerator pedal position sensor errors. This allows the detection of the degree of the accelerator pedal depression using signals from the working sensor, if either sensor malfunctions.The ECM uses the output value from the accelerator pedal position sensor for the fuel injection ●

volume control.

Hall ICMagnet

Magnet

Hall IC

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The accelerator pedal position sensor is composed of the moving contact and the resistive element, ●

and the output voltage varies depending on the accelerator pedal opening degree.As 5V from the ECM constant-voltage power supply circuit is connected through the variable ●

resistance of the sensor and resistance R, the voltage of the signal terminal varies in accordance with the sensor resistance value.The accelerator pedal position sensor has 2 types of circuits with different characteristics, and the ●

ECM reads the detected actual degree of the accelerator pedal and the accelerator pedal position sensor errors. This allows the detection of the degree of the accelerator pedal even if either sensor malfunctions.The ECM uses the output value from the accelerator pedal position sensor for the fuel injection volume ●

control.

Accelerator Pedal Position Sensor(Contact Type)

Rotor

Segment

TIP

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Circuit[2[

Accelerator Pedal Position Sensor Circuit<1<

ADC


Hall IC No.1

Hall IC No.2

Magnet

Magnet

5 VVCPA

VPA

EPA

VCP2

VPA2

EPA2

E1

Microprocessor

Accelerator Pedal Position Sensor ECM

Terminal Voltage<2< Sensor 1 ■

Problem Condition


(Accel Sensor Out No.1)VCPA

Sensor power source

VPASensor output

EPASensor ground

Normal (IG ON) 5 V Depends on 0 V Depends onVCPA open 5 V 0 V 0 V 0 to 0.2 V

VCPA short 0 V 0 V 0 V No communication with ECM (ECM processor down)

VPA open 5 V 0 V 0 V 0 to 0.2 VVPA short 5 V 0 V 0 V 0 to 0.2 VEPA open 5 V 5 V 0 V 4.5 to 5.0 V

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Sensor 2 ■Problem Condition


(Accel Sensor Out No.2)VCP2

Sensor power source

VPA2Sensor output

EPA2Sensor ground

Normal (IG ON) 5 V Depends on 0 V Depends onVCP2 open 5 V 0 V 0 V 0 to 0.2 V

VCP2 short 0 V 0 V 0 V No communication with ECM (ECM processor down)

VPA2 open 5 V 0 V 0 V 0 to 0.2 VVPA2 short 5 V 0 V 0 V 0 to 0.2 VEPA2 open 5 V 5 V 0 V 4.5 to 5.0 V

Character[3[ The sensor voltage varies linearly and the difference between the voltages of the sensors 1 and 2 ●

remains constant. Therefore, if an error occurs in either sensor, it can be detected.

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.00

VPAVPA2

5 10 15 20

Volta

ge (V

)

Accelerator Pedal Opening Angle (˚)

Fully Close

Fully Open

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Fuel Injection Volume Control


Throttle Position Sensor Data (ALE20 with 2AD-FHV) ■: Axel Position: Accelerator Position No.1: Accelerator Position No.2

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Throttle Position Sensor111

Description[1[ The throttle position sensor is composed of the hall IC and magnets, in which the magnetic field ●

changes depending on the opening degree of the throttle valve, thus detecting the opening degree of the diesel throttle valve.As 5 V from the ECM constant-voltage power supply circuit is applied to the sensor, the magnetic ●

field for the applied current flow inside the hall IC varies in accordance with the throttle valve opening degree, therefore, the applied current and the vertical magnetic field strength vary. Thus, the changes in the voltage generated perpendicular to the applied current and the magnetic field are sent to the ECM as the throttle valve opening degree signals.The ECM uses the value output from the throttle position sensor for the fuel injection volume control, ●

fuel injection timing control and EGR control.

Throttle Position SensorHall IC

Magnet

TIP

A new Avensis AD series engine has a DC motor type diesel throttle, and a throttle position sensor composed of the hall IC and magnets are used.

Hall IC

Magnet

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Circuit[2[

Throttle Position Sensor Circuit<1<

ADC


Hall IC

Magnet

VCVL

VLU

EVLU

E1

Microprocessor

Throttle Position Sensor ECM

Terminal Voltage<2<

Problem Condition


(Throttle Sensor Volt %)VCVL

Sensor power source

VLVSensor output

EVLVSensor ground

Normal (IG ON) 5 V Depends on 0 V Depends onVCVL open 5 V 0 V 0 V 0 %

VCVL short 0 V 0 V 0 V No communication with ECM (ECM processor down)

VLU open 5 V 0 V 0 V 0 %VLU short 5 V 0 V 0 V 0 %

EVLU open 5 V 5 V 0 V Approximately 100 %

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Character[3[

0

0.7

3.5

14 70.1 100

Acc

eler

ator

Ped

al O

peni

ng A

ngle

Ope

n

Volta

ge (V

)

Clo

se

Intelligent Tester Display

Actual Throttle PositionThrottle Pos. Sensor Outpu



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Throttle Position Sensor Data (ALE20 with 2AD-FHV) ■: Throttle Position Sensor Output: Actual Throttle Position

Diesel throttle valve closing direction

Diesel throttle valve opening direction

* The throttle position sensor output and the actual throttle position values are always opposite when they are output.

Learning of fully closed diesel throttle valve position ■The ECM performs the learning of fully closed diesel throttle valve position when the diesel throttle ●

valve is fully closed (when the ignition switch is off).Learning of the fully closed position can be checked by the 2 data list items, “Diesel Throttle Learn ●

Status” and “Diesel Throttle Learning Val”, by the data list function of an intelligent tester.The ECM performs the learning of the fully closed diesel throttle valve position, with the diesel ●

throttle valve opening degree value when the diesel throttle valve is fully closed set as the Diesel Throttle Learning Val. When the opening degree value is within the reference values (between 14.25 and 21.25 deg.), the ECM determines that the Diesel Throttle Learn Status is OK and normally terminates the learning of the fully closed diesel throttle valve position. When the opening degree is outside the reference values, the ECM terminates the learning of the fully close diesel throttle valve position and determines that the Diesel Throttle Learn Status is FAIL, with the fully closed diesel throttle valve at the default value of 21.25 degrees.

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Throttle Valve Fully Opened Switch121

Description[1[ The throttle valve fully opened switch is installed in the step motor type throttle body and the throttle ●

valve fully open position is detected using the ON/OFF contact.The ECM uses the output value from the throttle valve fully opened switch for the EGR control. ●

Throttle Valve Fully Opened Switch

Circuit[2[

Throttle Valve Fully Opened Switch Circuit<1<

12 V

THOP

Microprocessor

Interface

Throttle Valve Fully Open Switch

ECM

Terminal Voltage<2<

Problem Condition


(Throttle Open Switch)THOPSwitch Output

Normal(Engine running, accelerator pedal

fully depressed)0 V ON

Normal(Idling) 5 V OFF

THOP open 5 V Remains OFFTHOP short 0 V Remains ON

Throttle valve stuck(Stuck at fully opened position) 0 V Remains ON

Throttle valve stuck 5 V Remains OFF

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Character[3[ (Throttle Valve)

(Step Motor)No. of Step

Switch ONNear Fully Open

Near Fully Closed

Large Small


EGR Control

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Nozzle Vane Position Sensor131

Description[1[ The nozzle vane position sensor is used on a DC motor type of the variable nozzle vane turbocharger. ●

The nozzle vane position sensor is composed of the hall IC and the magnets, in which the magnetic ●

field changes depending on the opening degree of the movable nozzle connected to the DC motor, thus detecting the opening degree of the movable nozzle.As 5 V from the turbo motor driver constant-voltage power supply circuit is applied to the sensor, the ●

applied current inside the hall IC and the vertical magnetic field strength vary in accordance with the variable nozzle opening degree after the DC motor is started. Thus, the changes in the voltage generated perpendicular to the applied current and the magnetic field are sent to the turbo motor driver as the variable nozzle opening degree signals.There are 2 types of nozzle vane position sensor: single signal output and twin signal output ●

types. The dual signal output type sensor has 2 types of circuits with different characteristics, and detects the actual opening degree of the movable nozzle and even any nozzle vane position sensor malfunctions. This allows the detection of the opening degree of the movable nozzle if either sensor has a malfunction.The ECM uses the value output from the nozzle vane position sensor and the turbo motor driver for ●

the turbocharger control.

Hall IC

Magnet

Nozzle Vane Position Sensor

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Circuit[2[

Nozzle Vane Position Sensor Circuit<1< Single signal output type ■

ADC


Hall IC

Magnet

VNVC

VTA1

VNE2

GND

Microprocessor

Nozzle Vane Position Sensor Turbo Motor Driver

Twin signal output type ■

ADC Microprocessor


Hall ICNo.1

Hall ICNo.2

Magnet

Magnet

VNVC

VTA1

VNE2

VCS

VTA2

ES2

GND

Nozzle Vane Position Sensor Turbo Motor Driver

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Terminal Voltage<2< Sensor 1 (single signal output type or twin signal output type) ■

Problem ConditionTurbo Motor Driver Terminal Voltage

VNVCSensor power source

VTA1Sensor output

VNE2Sensor ground

Normal (Idling) 5 V Depends on 0 VVNVC open 5 V 0 V 0 V

VNVC short 0 V(driver down)

0 V(driver down)

0 V(driver down)

VTA1 open 5 V 0 V 0 VVTA1 short 5 V 0 V 0 VVNE2 open 5 V 5 V 0 V

Sensor 2 (Twin signal output type) ■Problem Condition

Turbo Motor Driver Terminal VoltageVCS

Sensor power sourceVTA2

Sensor outputE2S

Sensor groundNormal (Idling) 5 V Depends on 0 V

VCS open 5 V 0 V 0 V

VCS short 0 V(driver down)

0 V(driver down)

0 V(driver down)

VTA2 open 5 V 0 V 0 VVTA2 short 5 V 0 V 0 VE2S open 5 V 5 V 0 V

Character[3[

4.5

0.5

Volta

ge (V

)

Nozzle Vane PositionClosed Opened

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Turbocharger Control


The variable nozzle vane turbo opening degree and indicating value can be displayed on the ●

intelligent tester. However, the actual angle value cannot be displayed on it.To control the nozzle vane position, the turbo motor driver renders the contact position of the linkage ●

with the full-close stopper (thus fully closing the nozzle vane) as the zero point for the nozzle vane position sensor.

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EGR Valve Position Sensor1[1

Description[1[ The EGR valve position sensor is composed of a movable contact point and a resistive element, and ●

the output voltage varies depending on the EGR valve opening degree.As 5 V from the ECM constant-voltage power supply circuit is connected through the variable ●

resistance of the sensor and resistance R, the voltage of the signal terminal varies in accordance with the sensor resistance value.The ECM uses the value output from the EGR valve position sensor for the EGR control. ●

EGR Valve

EGR Valve Position Sensor

The EGR valve position sensor is composed of the hall IC and magnets, in which the magnetic field ●

varies depending on the opening degree of the EGR valve, thus detecting the EGR valve lift amount.5V from the ECM constant voltage power supply circuit is applied to the sensor. The gap between the ●

magnets and the hall IC in the EGR valve position sensor changes in accordance with the EGR valve lift amount, and at the same time, the magnetic field strength (voltage) varies. This magnetic change is output to the ECM after being converted to electronic signals.The ECM uses the value output from the EGR valve position sensor for the EGR control. ●

EGR Valve


TIP

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Circuit[2[

EGR Valve Position Sensor Circuit<1<

ADC


VCEG

EGLS

EEGL

E1

Microprocessor

EGR Valve Position Sensor ECM

Terminal Voltage<2<

Problem Condition


(EGR Lift Sensor Output)VCEG

Sensor power source

EGLSSensor output

EEGLSensor ground

Normal (IG ON) 5 V Depends on 0 V Depends onVCEG open 5 V 0 V 0 V 0 %

VCEG short 0 V 0 V 0 V No communication with ECM (ECM processor down)

EGLS open 5 V 0 V 0 V 0 %EGLS short 5 V 0 V 0 V 0 %EEGL open 5 V 5 V 0 V Approximately 100 %

Character[3[

5

4

3

2

0

1

Inte

llige

nt T

este

r Dis

play

0 %

100

%

Volta

ge (V

)

EGR Valve OpeningFully Closed

EGR Lift Sensor OutputTarget EGR Position

Fully Opened

+/- 10 %

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EGR Control


EGR valve position sensor data (VDJ200 with 1VD-FTV) ■: EGR Lift Sensor Output: Actual EGR Valve Position

EGR valve closing direction

EGR valve opening direction

* The EGR lift sensor output and the actual EGR valve position values are always opposite when they are output.

Learning of fully closed EGR valve position ■The ECM performs the learning of the fully closed EGR valve position, with the EGR valve opening ●

degree value when the ignition switch is on (when the EGR control is not performed) set as the EGR Close Learning Val.Learning of the fully closed position can be checked by the 2 data list items, “EGR Close LRN.” and ●

“EGR Close Learn Val.”, by the data list function of an intelligent tester.The ECM performs the learning of the fully closed EGR valve position, with the EGR valve opening ●

degree value at the time the ignition switch is on (when the EGR control is not performed) set as the EGR Close Learn Val., when the opening degree value is within the reference values (between 3.5 and 4.5, reference values for V/AD series engine), the ECM determines that the EGR Close LRN. Status is OK and terminates the learning of the fully closed EGR valve position normally. When the opening degree is outside the reference values, the ECM terminates the learning of the fully closed EGR valve position and determines that the EGR Close LRN. Status is FAIL, with the fully closed EGR valve position set as the default value 4V or the past opening degree value when operating normally.

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Air-fuel Ratio Sensor151

Description[1[ The air-fuel ratio sensor is provided at the rear of the DPF catalyst and DPNR catalyst and detects the ●

air-fuel ratio over the entire range of rich to lean.Approximately 0.4 V (AF+:3.3 V, AF-:2.9 V) is constantly applied to the A/F sensor. ●

The current flow direction and amount vary in accordance with the air-fuel ratio, however, the current ●

does not flow at the stoichiometric air-fuel ratio. This current is detected by the current detection circuit and is input into the microprocessor after digitally converted by the ADC (A/D converter). (The A/F sensor output can be checked by the converted voltage of 0 to 5 V for the A/F current and the air-fuel ratio by an intelligent tester.)The A/F sensor is activated only at high temperatures (650 ˚C or higher), therefore, the heater is ●

precisely controlled while the engine is running to detect a stable air-fuel ratio.The ECM detects the air-fuel ratio on the basis of the current on the AF+ terminal which varies ●

depending on the magnitude of the electromotive force.

ZirconiaCooting (Ceramic)

Dilation Layer

Atmosphere

Platinum Electrode

Heater

Alumina<A-A Cross Section>

AA

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Air-fuel ratio sensor current value ■Lean

Electromotive force < Approx. 0.4V

A/F Sensor

2.9 V + Electromotive force < 3.3 V

Direction & Strength of electric current are detected.

2.9 V Constant Voltage Circuit

AF-(2.9 V +

Electromotive force)

AF+(3.3 V)


A/F+A/F-

ECU

When the electromotive force is less than approx. 0.4V, the voltage at the AF+ terminal is higher ●

than the AF- terminal, therefore, the current flows in proportion to the voltage difference from the AF+ to the AF- terminal

Stoichimetric air-fuel ratioElectromotive force = Approx. 0.4V

A/F Sensor

2.9 V + Electromotive force = 3.3 V



AF-(2.9 V + Electromotive force: approx. 0.4 V)

AF+(3.3 V)


A/F+A/F-

ECU

When the electromotive force is approx. 0.4V, the voltage at both AF+ and AF- terminals are equal ●

and the current does not flow in either way

RichElectromotive force >Approx. 0.4V

A/F Sensor

2.9 V + Electromotive force > 3.3 V



AF-(2.9 V + Electromotive force)

AF+(3.3 V)


A/F+A/F-

ECU

When the electromotive force is more than approx. 0.4V, the voltage at the AF- terminal is higher ●

than the AF+ terminal and the current flows in proportion to the voltage difference from the AF- terminal to the AF+ terminal.

TIP

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Circuit[2[

Air-fuel Ratio Sensor Circuit<1<

ADC

DAC



Current Detection Circuit

AF+

AF-

MicroprocessorAir Fuel Ratio Sensor

ECM

Terminal Voltage<2<

Problem Condition

ECM Terminal VoltageValue on Data

List (AFS B1S1)AF+

Sensor positive terminal

AF-Sensor negative

terminal

HAF2Heater control

MRELECM and Heater

power controlNormal(IG ON) Depended on Depended on Pulse

generatedNear battery

voltage Depended on

AF+ Open 3.3 +/- 0.1 V 2.9 +/- 0.1 V Pulsegenerated

Near batteryvoltage 0 V

AF+ Short 0 V Approx. 1 V Pulsegenerated


AF- Open 3.3 +/- 0.1 V 2.9 +/- 0.1 V Pulsegenerated


AF- Short 3.3 +/- 0.1 V 0 V Pulsegenerated


HAF2 Open or Short Depends on Depends on 0 V Near battery

voltage Depends on

MREL Open 0 V(ECM down)

0 V(ECM down)

0 V(ECM down)

Near batteryvoltage

Communication unavailable

MREL Short 0 V(ECM down)

0 V(ECM down)

0 V(ECM down) 0 V Communication

unavailable

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A pulse signal which is output from the HAF2 terminal of the air-fuel ratio sensor controls the sensor heater. The zirconium elements used in the air-fuel ratio sensor cannot accurately judge the air-fuel ratio at low temperatures. Therefore, the sensor includes the heater so that the air-fuel ratio can be accurately judged by quickly heating the engine after the start-up.

Change in duty ration according to running conditions ■

100

1

2

34

550

0

Hea

ter D

uty

Rat

io (%

)

* The time it takes from 1 to 2 and duty ratio in 3 change with sensor temperatures.

1 The duty ratio right after cold start is 100%2 Duty control is ON after warm up3 Duty control is ON during driving4 The duty ratio during idling is 40 to 50 %5 The heater is OFF during high-speed driving

TIP

Character[3[ 2.0

1.5

1.0

0

0.5

Volta

ge (V

)

Air Fuel Ratio10 20 30 40 50

A constant voltage is applied to the terminal of the air-fuel ratio sensor and the current change is sent to the ECM by the sensor. The ECM converts the value output from the sensor into voltage and displays the output characteristics on the intelligent tester.

TIP

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Fuel Injection Volume ControlExhaust Emission Control


Air-fuel Ratio:The actual air-fuel ratio is one of the important elements to know about the engine conditions when searching for the cause of a malfunction in the common rail system. However, any items relevant to the air-fuel ratio cannot be displayed in the Data List functions of the Intelligent Tester. Obtain the actual air-fuel ratio from either item: Air fuel ratio fuel trim value (Air ratio) [AF Lambda B1S1] or Air-fuel ratio sensor output voltage [AFS Voltage B1S1]. Follow the formulas below to obtain the air-fuel ratio.

1. When the value of the AF Lambda B1S1 is less than 1.99 the actual air-fuel ratio can be calculated by using a formula below.

Actual air-fuel ratio = 14.5 x [AF Lambda B1S1] Example calculation: if AF Lambda B1S1 is 1.2, actual air-fuel ratio = 14.5 x 1.2 = 17.42. When the value of the AF Lambda B1S1 is 1.99 or more, in this case use the following table to

determine the actual air-fuel ratio based on the output voltage of the air-fuel ratio sensor [AFS Voltage B1S1]. If AFS voltage B1 S1 is 1.1 V, the actual air fuel ratio is around 33 to 34

AF Lambda B1 S1

AFS B1 S1

Air = Fuel Ratio

AF Lambda B1 S1 = Air-Fuel Ratio / 14.5

2

2(V)

10 20 30 40 50

1

1

0

0

AFS Voltage B1S1 * * * 0 0.065 0.174 0.274 0.361 0.513 0.787 1.013 1.579AF Lambda B1S1 0.828 0.897 0.966 1 1.034 1.103 1.172 1.241 1.379 1.724 * *

Air-fuel ratio 12 13 14 14.5 15 16 17 18 20 25 30 50

*: On the Intelligent Tester, values exceeding 1.99 for the AF Lambda B1S1 cannot be displayed and negative values for the AFS Voltage B1S1 cannot also be displayed.

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Differential Pressure Sensor161

Description[1[ The differential pressure sensor, which outputs changes in the pressure applied to the built-in silicon ●

chip as electric signals, detects the pressure of the DPF and DPNR catalytic converters.5 V from the ECM constant-voltage power supply circuit is applied to the sensor, and the silicon IC ●

resistance varies in accordance with the pressure before and after catalyzation, and the change in the resistance is converted into a voltage change by the built-in IC and is output to the ECM. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The ECM uses the value output from the differential pressure sensor for after-treatment control. ●

Differential Pressure Sensor

Sensor Unit

For the DPF catalytic converter with a exhaust gas control valve, the pressure in the DPF catalytic converter is detected by the absolute pressure sensor.

TIP

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Circuit[2[

Differential Pressure Sensor Circuit<1<

ADCIC

5 V Constant Voltage CircuitVCPX

PEX

EPEX

E1Microprocessor

Differential Pressure Sensor ECM

Terminal Voltage<2<

Problem Condition

ECM Terminal Voltage Value on Data List (DPF Differential

Pressure)VCPX

Sensor power sourcePEX

Sensor outputEPEX

Sensor groundNormal (IG ON) 5 V Approximately 0.75 V Approximately 0.4 V Approximately 0 kPa

VCPX open 5 V Approximately 0 V 0 V -5 kPa

VCPX short Approximately 0 V Approximately 0 V 0 VNo communication

with ECM (ECM processor down)

PEX open 5 V 5 V 0 V 100 kPaPEX short 5 V 0 V 0 V -5 kPa

EPEX open 5 V 5 V 0 V 100 kPa

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Character[3[ The pressure difference pulsates strongly as it is affected by the engine exhaust pulsation, and is ●

averaged by the ECM. The pressure difference can be calculated accurately even at low difference pressures by being measured in negative values.

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0

Volta

ge (V

)

Pressure (kPa)

-10 0 10 20 30 40 50 8060 9070 100


After-treatment

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Exhaust Temperature Sensor171

Description[1[ Exhaust temperature sensors are provided at the front and rear of the DPF catalyst and the DPNR ●

catalytic converter.The exhaust temperature sensor has a built-in thermistor, in which its resistance varies depending ●

on the exhaust gas temperature, and detects the exhaust gas temperature at the front and rear of the DPF catalytic converter and DPNR catalytic converter. The higher the thermistor resistance is, the lower the exhaust gas temperature is, and similarly the higher the exhaust gas temperature is, the lower the thermistor resistance is.As 5 V from the ECM constant-voltage circuit is applied to the sensor through the resistance R, the ●

voltage of the signal terminal varies in accordance with the sensor resistance value. This signal is input into the microprocessor after being digitally converted by the ADC in the ECM.The upstream sensor is mainly used to determine an estimated catalyst temperature, injection amount ●

from the exhaust fuel addition injector and injecting timing, and the downstream sensor is used to judge the increase in the catalyst temperature (active state of catalyst).The ECM uses the value output from the exhaust temperature sensor for after-treatment control. ●

Exhaust Gas Temperature Sensor

Thermistor

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Circuit[2[

Exhaust Temperature Sensor Circuit<1< Different terminal for each circuit on ground side ■

ADC

5 V Constant Voltage Circuit

THCI

THCO

ETCO

ETCI

E1

MicroprocessorExhaust Gas Temperature Sensor (Front)

Exhaust Gas Temperature Sensor (Rear)

ECM

Same terminal for each circuit on ground side ■

ADC

5 V Constant Voltage Circuit

THCI

THCO

E2

E1

Exhaust Gas Temperature Sensor (Front)

Exhaust Gas Temperature Sensor (Rear)

Microprocessor

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Terminal Voltage<2< Exhaust Gas Temperature Sensor B1S1(in front of Catalyst) ■Problem Condition

ECM Terminal Voltage Value on Data List(Exhaust Temperature

B1S1)THCI

Sensor outputETCI (E2)

Sensor groundNormal (IG ON) Depends on 0 V Depends on

THCI open 5 V 0 V 0 ˚CTHCI short 0 V 0 V 1000 ˚C

ETCI (E2) open 5 V 0 V 0 ˚C

Exhaust Gas Temperature Sensor B1S2(behind Catalyst) ■Problem Condition

ECM Terminal Voltage Value on Data List(Exhaust Temperature

B1S2)THCO

Sensor outputETCO (E2)

Sensor groundNormal (IG ON) Depends on 0 V Depends on

THCO open 5 V 0 V 0 ˚CTHCO short 0 V 0 V 1000 ˚C

ETCO (E2) open 5 V 0 V 0 ˚C

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Character[3[

0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

Temperature (˚C)

Volta

ge (V

)

-40 160 360 560 760 960 1000

REFERENCE The output characteristics of the upstream and downstream catalysts are the same. ●

At temperatures outside of the use temperature range (50 to 850 ˚C, the thermistor tolerance is large, ●

therefore it’s difficult to judge whether the thermistor is normal or not using the resistance value.

Exhaust gas temperature ■Engine Condition Data motor output temperature

After warm up and drive or idling 150 to 350 ˚CUnder control of catalyst generation 500 to 700 ˚C


After-treatment

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5 Actuators7

Suction Control Valve11

Suction Control Valve in HP2 type Supply Pump[1[

Description<1< The suction control valves (SCVs) used in the HP2 supply pump are fitted on the two pressurized fuel ●

feeding systems, and regulate the fuel intake amount through the time duration that the fuel passages are open (the electromagnetic valves turn ON and OFF). The suction control valves incorporate a solenoid electromagnetic valve consisting of a coil, a spring, and a needle valve.

Suction Control Valves

Needle Valve

StopperFrom feed pump

Spring

Coil

When SCV is ON

To feeding area

Outline of Suction Control ■Suction control start

The coil is energized by the ECM, and when the electromagnetic force of the coil overcomes the spring force that closes the needle valve, the needle valve will open, letting the fuel come in.

Suction control end The energization of the coil is cut off by the ECM, thus, the needle valve will shut due to its spring force, and the fuel suction will stop.

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Operation<2< Since the fuel suction timing (SCV turns ON) is constant due to the crank position sensor signal ●

(determined by the pump speed), the amount of fuel intake is regulated by the timing of the fuel suction end (SCV turns OFF). Therefore, the earlier the SCV turns OFF, the smaller the fuel intake amount becomes, and the later the SCV turns OFF, the larger the fuel intake amount becomes.During the fuel suction process, the plunger moves outward along with the cam face due to the fuel ●

feeding pressure, however, when the fuel suction ends, the plunger will stop moving at that position. As the fuel intake amount varies between 0 to 100%, except the situation when the fuel comes in at the maximum extent, the roller is not coming in contact with the cam face during the period from the fuel suction end until the fuel feeding start.

Suction

Feeding

Feeding Suction

Suction

Feeding

Feeding

Feeding

Feeding Suction

Suction

Suction

Suction

Suction

Increase in Suction Volume

Suction

Suction

OFF

OFF

OFF

OFF

OFF

Roller

SCV

Plunger

Delivery Valve

Check Valve

OFF

ON

ON

Fuel

Fuel

ON

ON

OFF

OFF

SCV 1

SCV 2

Delivery Valve Discharge

Cam Lift Horizontal Direction

Cam Lift Vertical Direction

Fuel

Fuel

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Circuit<3<

Suction Control Valve in HP2 Supply Pump Circuit(1)

Constant Current Drive Circuit

12 V

COM

PCV1

PCV2

E1

ECM

No.1 Suction Control Valve

No.2 Suction Control Valve

Drive Circuit

Microprocessor


Active Test ■Active Test Item Test Detail/Control Range

Test the Fuel Leak Pressurizes common rail internal fuel pressure, and checks for fuel leaks:Stop/Start

The applicable items vary depending on the vehicle. For details about the Active Test, refer to the * relevant repair manuals.

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Suction Control Valve in HP3 and HP[ type Supply Pump[2[

Description<1< The suction control valve used in the HP3 and HP4 supply pumps is fitted on the inlet portion of the ●

pressurized fuel feeding system, and regulates the fuel intake amount by changing the fuel passage area where the fuel flows through. The suction control valve incorporates a solenoid electromagnetic valve.The fuel passage area enlarges or reduces in accordance with the valve lift of the suction control ●

valve that is regulated by the current value (drive duty ratio) from the ECM.

Suction Control Valve

To feeding area

To feeding area

From feed Pump

Low fuel intake amount(SCV opening degree is small)

High fuel intake amount(SCV opening degree is large)

Outline of Suction Volume Control ■Low fuel intake amount

Since the drive duty ratio applied to the electromagnetic valve is small and the opening degree of the SCV decreases, the amount of fuel drawn by the plunger working in the suction stroke also decreases.

High fuel intake amount

Since the drive duty ratio applied to the electromagnetic valve is large and the opening degree of the SCV increases, the amount of fuel drawn by the plunger working in the suction stroke increases as well.

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Operation<2<

General(1) By changing the current value applied to the suction control valve, the ECM controls the opening ●

degree of the suction control valve.Depending on the changes in the current value applied to the suction control valve, the ECM ●

generates SCV drive duty signals.

High fuel intake amount(SCV opening degree is large)

SCV Current Cam

Stroke

Plunger TDC

Fuel Pumping Mass

Plunger TDC

Cam Stroke

SCV Current

ON +BPCV+

TerminalOFF 0 V

ON +BPCV+

TerminalOFF 0 V

Low fuel intake amount(SCV opening degree is small)

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Operation during the Active Test(2) Data under the fuel leak test (ALE20 with 2AD-FHV) ■

When active test is conducted, target common-rail pressure rises up to maximum level

Active test is conducted

Amount of fuel fed to supply pump increases, thus, common-rail pressure rises

In order to achieve target common-rail pressure, SCV current is boosted, increasing SCV opening degree

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Data under the same conditions as the above Active Test (2000 rpm with no load) ■

In comparison to the data monitored under the same conditions, when the SCV current rises by 50 mA, the common-rail pressure increases approximately 128 MPa.

POINT

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Circuit<3<

Suction Control Valve in HP3 and HP[ Supply Pump Circuit(1)

12 V

PCV+

PCV-

E1

ECM


Drive Circuit

Current Monitor

Drive Circuit

Fail Detection

Microprocessor



Test the Fuel Leak Pressurizes common rail internal fuel pressure, and checks for fuel leaks:Stop/Start


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Pressure Discharge Valve21

Description[1[ If the fuel pressure inside the common-rail is higher than the target pressure, the pressure discharge ●

valve is opened while releasing the excess pressure such as during deceleration and engine stop to return the fuel to the fuel tank using the fuel return pipe. The pressure discharge valve is an electromagnetic valve that consists of a coil, a spring, and a plunger.When the coil is energized, the plunger is lifted up and the fuel is released to the return pipe. The coil ●

is energized by the EDU (Electronic Driving Unit) controlled by the drive request signal transmitted from the ECM. However, for the models with both the pressure limiter and the pressure discharge valve, the pressure discharge valve is directly connected to the ECM and driven directly.By releasing the excess pressure using the pressure discharge valve, the actual fuel pressure ●

decrease ability and the adherence to the common-rail target fuel pressure is improved to apply appropriate injection pressure to the injectors while the engine is running. In addition, if the fuel pressure inside the common-rail is too high, the ECM sends the valve open signal to the pressure discharge valve and releases the fuel pressure to protect the system.*

* For models with both the pressure limiter and the pressure discharge valve, the pressure limiter mechanically releases the pressure if too high.

Pressure Limiter


Plunger

Valve Open

To Fuel Tank


Outline of Pressure Discharge Specification ■Model Target fuel

pressure controlExcess fuel

pressure releaseAbnormally high pressure release Drive system

2KD-FTV KDY2## / KDN1##KLH1#, 2#

(01/08-06/08)○ ○ Pressure limiter Directly by ECM

For all models except the above-mentioned models ○ ○ ○ Driven by EDU

controlled by ECM

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Operation[2[

General<1< In case of sudden deceleration (when the accelerator pedal is suddenly depressed) or a sudden ●

fuel pressure rise, the ECM drives the pressure discharge valve to quickly decrease the pressure to prevent the fuel pressure from becoming too high.

Sudden deceleration

Accelerator depression degree

Injector injection pulse

Pressure discharge valve drive pulse

Rail pressure Target pressure

Actual rail pressure

w/o pressure discharge valve

REFERENCE The pressure discharge valve drive request signal output timings are not affected by the injector ●

injection signals.

Operation when the pressure discharge valve is defective<2< Data when normal (ALE20 with 2AD-FHV) ■

: Fuel Press: Target Common-rail Pressure

* The common-rail pressure is reduced In accordance with the target common-rail pressure, hence, it is regulated without lagging behind the target common-rail pressure.

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Data when circuit is open (ALE20 with 2AD-FHV) ■: Fuel Press: Target Common-rail Pressure

* Since the pressure discharge valve does not operate, the common-rail pressure cannot be reduced in accordance with the target common-rail pressure, a lag occurs.

Circuit[3[

Pressure Discharge Valve Circuit<1< Driven by EDU Controlled by ECM ■

Microprocessor


DC/DC Converter

Injector Driver (EDU)

12 V

+B

GND

#1

COM3

COM2

COM1

INJ1

INJ4

INJ2

INJ3

PRV


#4

#2

#3

PRD

INJF

Waveform Shaping

Fail Detection

Constant Current

Injector

Mono- Stable

Driver

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Directly by ECM ■12 V

COM

PRV

E1

ECM


Drive Circuit

Microprocessor

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EDU (Electronic Driving Unit)31

Description[1[ In order to drive the injectors at high speeds with high voltage and high current, the ECU incorporates ●

an injector driver equipped with a DC-DC converter that is exclusively used for the injectors. The EDU converts injection request signals, which are transmitted from the ECM, into injector signals to control the injectors.Since the EDU generates high voltage and high current, it is separated from the ECM to prevent the ●

noise affecting the ECM.In engines in which the common-rail has a pressure discharge valve, the EDU drives the pressure ●

discharge valve and transmits valve drive confirmation signals to the ECM in the same way as the injectors.

REFERENCE When the common-rail has both the pressure limiter and the pressure discharge valve, the ECM drives ●

the pressure discharge valve directly.

Operation[2[ By receiving the injection timing signal from the ECM, which is calculated based on the sensor ●

signals, the EDU transmits the injector drive signal to the injectors. In addition, the EDU transmits the injection confirmation signal, which can be obtained from the current flowing through the injector drive circuit, to the ECM.The power is not constantly supplied to the positive terminal of an injector, for the duration that the ●

ECM requests injection, a high voltage is applied. Simultaneously with the power supply activation, the EDU connects the negative terminal of an injector to the ground, energizing the injector. The EDU has the high side SW for the injector power control and the driver circuit for the ground control, and accurately drives the injectors through the controls.The EDU regulates the injector to decrease the injector operation voltage and speed upon receiving ●

a signal, that indicates idling conditions, from the ECM in order to reduce the injector operation noise while idling.

Timing Chart

Injection Timing Signal

Injection Current

Fail Safe Signal

Injector Low Side Voltage

Injector High Side Voltage

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Circuit[3[

EDU Circuit<1< The injector drive request signal (INJ#) transmitted by the ECM is input to the monostable circuit to ●

the high side SW, and to the driver circuit, passing through the waveform shaping circuit. Coincident with a high voltage application COM1 by the high side SW, the driver lets INJ1 flow into the ground. When the INJ injection current exceeds a certain voltage, the ECU transmits the drive confirmation signal (INJF) to the ECM.

Microprocessor


DC/DC Converter

Injector Driver (EDU)

12 V

+B

GND

#1

COM3

COM2

COM1

INJ1

INJ4

INJ2

INJ3

PRV


#4

#2

#3

PRD

INJF

Waveform Shaping

Fail Detection

Constant Current

Injector

Mono- Stable

Driver

SJG 殿からデータ提供待ち。（メモハイデータ）

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Control the Cylinder#1 Fuel CutControl the Cylinder#2 Fuel CutControl the Cylinder#3 Fuel CutControl the Cylinder#4 Fuel CutControl the Cylinder#5 Fuel CutControl the Cylinder#6 Fuel CutControl the Cylinder#7 Fuel CutControl the Cylinder#8 Fuel Cut

Cut off fuel injection from No. 1 to 8 injector:ON/OFF

Control the All Cylinders Fuel Cut All cylinder injector fuel cut:ON/OFF

The injection signals* shown in the Data List are the values calculated by the ECM, thus, an Intelligent * Tester cannot show the actual injection signals (EDU output signals).Main Injection Period, Pilot 1 Injection Period, Pilot 2 Injection Period, and After Injection Period* The applicable items vary depending on the vehicle. For details about the Active Test, refer to the * relevant repair manuals.

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Swirl Control Valve[1

Outline of Swirl Control Valve[1[ The swirl control valve generates strong swirls inside the cylinder and stabilizes combustion to largely ●

reduce smoke emissions. In addition, the swirl control ensures combustion stability while driving with a large amount of EGR.There are two types of swirl control valves; one that controls vacuum for the vacuum controller in two ●

stages, open and closed, using one VSV and the other that controls the vacuum in three stages, fully open, half open and fully closed using two VSVs.

Swirl Control Valve

Swirl Control Valve Actuator

VSV for Swirl Control Valve

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11VSV drive[2[

Description<1< The SCV consists of a shaft with a valve that is installed into the intake manifold, a vacuum actuator ●

and a VSV that switches pressure for the actuator.The ECM determines the swirl control valve opening angle in accordance with the engine conditions ●

and controls the swirl control valve opening angle in two stages (fully open and fully closed) by switching vacuum applied to the actuator diaphragm chamber via the VSV.In the low engine speed range, the valve is closed and the swirl inside the cylinder becomes stronger ●

to enhance the mixture of fuel and air in order to achieve stable combustion. As a result, smoke was reduced. However, when the engine is cold, white smoke is reduced by fully opening the valve and increasing the intake air amount.

Actuator

Air Intake Chamber

Swirl Control Valves

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Operation<2< The battery voltage is constantly supplied to the VSV that switches the vacuum applied to the vacuum ●

actuator diaphragm chamber while the ignition switch is on. The ECM controls the VSV by switching the VSV ground side circuit. The ECM turns the transistor on and shorts the SCV terminal potential to ground to energize the VSVs when closing the swirl control valve.

Circuit<3<

VSV Drive Circuit(1)

12 V

MAIN

Battery

SCV

MREL

E1

ECM

Swirl Control ValveDrive Circuit

Fail Detection Circuit *

Microprocessor

Drive Voltage(2)

Problem ConditionECM Terminal Voltage Value on Data List

(Swirl Control Valve VSV)SCV Switch InputNormal (Low speed, Low load) 0 V ON

Normal (High speed, Heavy load) 12V OFFSCV circuit open Remains 0 V Remains ONVSV itself shorted Remains 12V Remains OFF



Activate the VSV for Swirl Control Valve Activate VSV for No. 1 Swirl Control Valve:ON/OFF


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21VSV drive[3[

Description<1< The SCV consists of a shaft with valve that is installed into the intake manifold, two vacuum actuators ●

and two VSVs that switch pressure for the actuator.The ECM determines the swirl control valve opening angle in accordance with the engine conditions ●

and switches vacuum for the diaphragm chamber via the two VSVs, to control the swirl control valve opening angle in three stages (fully open, half open and fully closed).The 2-VSV drive system allows optimal swirl generation in accordance with the engine conditions ●

by controlling the swirl control valve opening angle in three stages in order to improve combustion efficiency and exhaust performance.

Actuator

Air Intake Chamber

Swirl Control Valves

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Operation<2< The battery voltage is constantly supplied to the VSV that switches the vacuum applied to the vacuum ●

actuator diaphragm chamber while the ignition switch is on. The ECM controls the VSV by switching the two VSV ground side circuits. The ECM turns the transistor on and shorts the SCV terminal potential to ground to energize the VSVs when closing the swirl control valve.

Circuit<3<

2-VSV Drive Circuit(1)

12 V

MAIN

Battery

SCV

SCV2

MREL

E1

ECM

No.1 Swirl Control Valve

No.2 Swirl Control Valve

Drive Circuit

Fail Detection Circuit

Microprocessor

Drive Voltage(2)


Value on Data List(Swirl Control Valve VSV)SCV

Switch InputSCV2

Switch InputNormal

(Low speed, Low load) 0 V 0 V ON

Normal(Medium speed, in

transition)0 V 12 V ON

Normal(High speed, Heavy load) 12 V 12 V OFF

SCV circuit open 0 V Depends on Remains ONNo. 1 VSV itself shorted 12V Depends on Remains OFF

SCV2 circuit open Depends on 0 V Depends onNo. 2 VSV itself shorted Depends on 12V Depends on

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Activate the VSV for Swirl Control Valve Activate VSV for No. 1 Swirl Control Valve:ON/OFF


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Variable Nozzle Vane Type Turbocharger51

Outline of Variable Nozzle Vane Type Turbocharger[1[ The variable nozzle vane type turbocharger opens and closes the variable nozzle located on the outer ●

circumference of the turbine and adjusts the velocity and the pressure of the exhaust gas flow taken into the turbocharger, in order to control the back pressure and boost pressure so as to take optimal balance against the engine speed and engine load.The variable nozzle vane type turbochargers can be divided into 3 types depending on the variable ●

nozzle drive system.As a basic control, the feedback control is conducted to gain a boost pressure determined from the ●

engine operating conditions (lower the boost pressure: open the variable nozzle, increase the boost pressure: close the variable nozzle).

Impeller

Open Close

Turbine

Nozzle Vane

To Exhaust Pipe

Variation of Variable Nozzle Vane Type Turbocharger ■Type

Step motor DC motor Vacuum actuator

1KD-FTV 1KD-FTV1VD-FTV

1CD-FTVAD Series etc.

Nozzle vane drive Step motor DC motor Vacuum actuator

Nozzle vane drive control

Controlled by the ECM directly.

Controlled by the turbo motor driver that is controlled by the ECM.

Controlled by regulating the vacuum taken into the actuator with the VRV that is controlled by the ECM.

Nozzle vaneposition detection

Determined by the number of steps calculated by the ECM.

Nozzle vane position sensor No detection

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Basic Control of Variable Nozzle Vane Type Turbocharger ■Engine Condition Purpose

Low and medium engine speed To improve boost pressure increase characteristicsTo reduce black smoke emission

High engine speed To improve fuel economy and outputTo prevent turbine overspeed

During EGR operation To stabilize EGR amount

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Step motor[2[

Description<1< The step motor is used to open and close the variable nozzle vanes. The turbocharger driven by the ●

step motor consists of variable nozzle vanes, a step motor (stator core and rotor), and a linkage that couples the variable nozzle vanes and the step motor.The ECM monitors the engine operating conditions using the various sensors, and calculates the ●

number of directive steps. Based on the calculation, the ECM energizes the step motor. The motor rotates a number of degrees according to the number of directive steps, opening or closing the variable nozzle via the coupled linkage.

Step Motor

Turbine

Nozzle Vane

Linkage

REFERENCE The turbocharger driven by the step motor compensates for the exhaust gas flow amount variation ●

depending on the turbine individual differences using the turbocharger compensate resistor resistance values. A turbocharger compensate resistor that matches each turbine is installed to regulate the amount of exhaust gas flow of a step to be uniform.

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Operation<2< The battery voltage is applied to the four coils built into the step motor while the engine is running, ●

and the ground sides of the coils are connected to the ECM. The ECM operates the step motor in incremental steps by switching the coil grounds, to regulate the nozzle vanes to the appropriate position according to the engine conditions.The built-in rotor of the step motor rotates in the normal or reverse direction by an incremental angle ●

by the signal transmitted from the ECM to the stator coil. The linkage is moved upward or downward by the amount of the rotor rotation, the ECM drives the step motor so that the actual step position of the step motor can follow the target step position.

Circuit<3<

Step Motor Drive Circuit(1)

Microprocessor

Microprocessor


ECM

Step Motor(VN Turbo)

MAIN

Turbocharger Compensate Resistor

12 V

R

R

VN-B

VN+B

VN-A

VN+B

VN-B

VTB

E2

E1

Battery

Drive Circuit

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Step Motor Movement: ■The 1-2 phase excitation drive method and the 2-phase excitation drive method are used to operate ●

the step motor.While the 1-phase excitation rotates the rotor by energizing a coil phase-by-phase, the 2-phase ●

excitation energizes a coil two-by-two, increasing the torque that rotates the rotor. The 1-2 phase excitation can halve the amount of rotor rotation per energization by alternating the 1-phase and 2-phase excitations.In accordance with the engine operating conditions, the ECM accurately controls the step motor with ●

a 1-2 phase excitation or the 2-phase excitation. The step motor is controlled in up to 470 incremental steps (235 steps if only 2-phase excitation), with a motor rod (linkage) stroke of 11mm between the full close to full open positions.

2-Phase ExcitationCoil

Coil

Coil

Coil

Rotational Amount

Rotational Amount

Energized

Not Energized

Rotor (magnet)

Rotor (magnet)

Rotor (magnet)

Rotor (magnet)

1-2 Phase Excitation

Terminal Arrangement

: Energized

2-Phase Excitation1-2 Phase Excitation

Direction Close Open

Combination of Energization Coils

Equivalent Circuit

Rotor

S1

B1

S3

S2 B2 S4

S2

S1

S2

S3

S4

S1

B2 B1

S4 S3

TIP

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Test the Turbo Charger Step Motor Activate Step Motor for Turbocharger:ON/OFF


REFERENCE An Intelligent Tester cannot show the step motor actual number of steps. ●

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DC motor[3[

Description<1< The DC motor is used to open and close the variable nozzle vanes. By using the DC motor, the ●

variable nozzle vane control responsiveness is improved and the variable nozzle vane boost rate is improved due to expansion of the variable nozzle vane close operation range.The turbocharger driven by the DC motor consists of variable nozzle vanes, a DC motor, a linkage ●

that couples the variable nozzle vanes and the DC motor, and a nozzle vane position sensor.The motor is driven by the turbo motor driver controlled by the request signals output from the ECM. ●

Turbine

Nozzle Vane

DC Motor

Linkage

Operation<2< The vane nozzle opening angle signal, of which value is determined from the engine speed and ●

injection volume, is input from the ECM to the turbo motor driver. The turbo motor driver drives the DC motor so that the nozzle vane position signal becomes same as the vane nozzle opening angle signal output from the ECM.The rotation of the DC motor opens and closes the nozzle vanes via the linkage provided on the ●

motor, regulating the exhaust gas pressure and the amount of the EGR gas flow.

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Circuit<3<

DC Motor Drive Circuit(1)

Microprocessor

ADC


Microprocessor

ADC

12V Constant Voltage Circuit5V Constant

Voltage Circuit

ECM

Drive Status Output Circuit

Motor Drive Request CircuitMotor Drive Circuit

Turbo Motor Driver

DC Motor

12 V

5 V

5 V

M

BNTO

VNTI

GND

+B

+B



Test the Turbo Charger Step Motor Activate DC motor for turbocharger:40 to 100%


REFERENCE An Intelligent Tester cannot show the actual position of the variable nozzle vanes that is output from ●

the nozzle vane position sensor.

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Vacuum Actuator Drive[[[

Description<1< The vacuum actuator is used to open and close the variable nozzle vanes. The turbocharger driven by ●

the DC motor consists of variable nozzle vanes, a vacuum actuator, a vacuum switching valve (E-VRV), and a linkage that couples the variable nozzle vanes and the vacuum actuator.According to the engine operating conditions, the ECM operates the electric vacuum regulating valve ●

(E-VRV) to regulate the volume of vacuum acting at the diaphragm chamber of the vacuum actuator.

Turbine

Nozzle Vane

Actuator

ActuatorLinkage

Operation<2< When the variable nozzle vanes need to be opened, the ECM boosts the current (duty signal) applied ●

to the vacuum regulating valve to increase the vacuum volume that is taken from the vacuum pump to the vacuum actuator. Conversely, when the vanes need to be closed, the ECM reduces the current to let atmospheric air come into the diaphragm chamber of the vacuum actuator, decreasing the vacuum volume taken from the vacuum pump. The position of the variable nozzle vane is controlled by the volume of vacuum of the diaphragm.

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Circuit<3<

Vacuum Actuator Drive Circuit(1)

Microprocessor

Microprocessor


ECM

E-VRV for TurbochargerMAIN

12 V

12 V

VN

MREL

E1

Battery

Drive Circuit

Drive Circuit

Current Monitor Circuit




Test the Turbo Charger Step Motor Activate DC motor for turbocharger:40 to 100%


REFERENCE An Intelligent Tester cannot show the actual position of the variable nozzle vanes. ●

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EGR Valve61

Outline of EGR Valve[1[ The EGR system is a system that recirculates the exhaust gas partially to the intake passage to lower ●

the peak temperature inside the combustion chamber, in order to reduce NOx emissions primarily. Since the ECM precisely regulates the amount of EGR gas by opening and closing the EGR valve according to the engine operating conditions and by letting enough EGR gas enter by reducing the intake manifold pressure by limiting the intake air using the diesel throttle, the engine output as well as drivability are not impaired.The EGR valve is fitted on the exhaust port or the bypass passage (EGR passage) provided in ●

between the intake passage and the exhaust manifold, and is divided into four types depending on the EGR valve drive systems.

ECM

Intercooler

EGR Cooler

EGR Valve

Diesel Throttle Body

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Variation of EGR valve ■Type

Vacuum actuator Step motor Linear solenoid DC motor

2KD-FTV KD Series1CD-FTV 1CD-FTV AD Series

1VD-FTVAD series

(for New Avensis)EGR valve drive system Vacuum actuator Vacuum actuator Step Motor Linear

Solenoid DC Motor

EGR Valve Type Gate Gate Gate Gate Butterfly

EGR valve lift control

Contro l led by regulating the vacuum taken into the actuator w i th the VRV that is controlled by the ECM.

In add i t i on to t he mechanism described on the left, the EGR cut-off control via the VSV is performed.



EGR Valve position detection

EGR valve position sensor

No detection

EGR valve position sensor


EGR valve p o s i t i o n sensor

Under the following engine conditions, higher priority is placed on quick engine warm-up and acceleration, and the ECM stops the EGR control. In addition, the EGR control will be stopped if the EGR control is performed for a long time during idling because it may result in white smoke emission due to the combustion temperature fall.

Low engine coolant temperature of below 15°C. (The temperature that allows the EGR control to start ●

varies depending on the vehicles)High engine speed of above 3500rpm. (The engine speed that stops the EGR control varies depending ●

on the vehicles)High engine load, such as when the accelerator pedal is fully depressed. ●

TIP

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Vacuum Actuator Drive[2[

Description<1< The vacuum actuator is used to open and close the EGR valve. The EGR valve system driven by the ●

vacuum actuator consists of an EGR valve (vacuum actuator), a vacuum regulating valve (E-VRV), a vacuum damper, and the ECM that controls the vacuum regulating valve. In some of the EGR systems that have the vacuum actuator, an EGR cut VSV, which has high responsiveness for when the EGR control is inactive, and an EGR valve lift sensor, which detects the EGR valve position used when conducting the feedback control for the EGR amount, are also used. According to the engine operating conditions, the ECM operates the electric vacuum regulating valve ●

(E-VRV) to regulate the volume of vacuum acting on the diaphragm chamber of the vacuum actuator.


E-VRV for EGR


E-VRV Cut VSV

Intake Air To Intake Manifold

EGR Gas

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Operation<2< When the EGR valve needs to be opened, the ECM boosts the current (duty signal) applied to the ●

vacuum regulating valve to increase the vacuum volume that is taken from the vacuum pump to the vacuum actuator. Conversely, when the valve needs to be closed, the ECM reduces the current to let atmospheric air come into the diaphragm chamber of the vacuum actuator, decreasing the vacuum volume taken from the vacuum pump. The EGR valve position is controlled by the volume of vacuum of the diaphragm.In the system with the EGR cut VSV, the VSV is activated when the EGR valve is promptly closed in ●

order to release the vacuum from the diaphragm chamber.

Circuit<3<

Vacuum Actuator Drive Circuit(1) Without EGR Cut VSV ■

Microprocessor

Microprocessor


ECM

E-VRV for EGRMAIN

12 V

12 V

EGR

MREL

E1

Battery

Drive Circuit

Drive Circuit



With EGR Cut VSV ■

Microprocessor

Microprocessor


ECM

VSV for EGR Cut

E-VRV for EGRMAIN

12 V

12 V

EGR

EGRC

MREL

E1

Battery

Drive Circuit

Drive Circuit

Drive Circuit



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Control the EGR System Activate E-VRV (for E-EGR):ON/OFF

Activate the VSV for EGR Cut Activate VSV (for EGR Cut):ON/OFF


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Step motor[3[

Description<1< The step motor is used to open and close the EGR valve. The EGR valve system driven by the step ●

motor consists of a step motor (stator core and rotor), a valve, and the ECM that controls the step motor. Compared to the EGR valve system which is driven by the vacuum actuator, the EGR volume can be regulated more accurately.The ECM monitors the engine operating conditions using the various sensors, and calculates the ●

number of directive steps. Based on the calculation, the ECM energizes the step motor. The motor rotates a number of degrees according to the number of directive steps, opening or closing the EGR valve.

EGR Valve

Exhaust Gas OUT(To Intake Manifold)

Exhaust Gas IN(From Exhaust Manifold)

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Operation<2< The battery voltage is applied to the four coils built into the step motor while the engine is running, ●

and the ground sides of the coils are connected to the ECM. The ECM operates the step motor in incremental steps by switching the coil grounds, to regulate the EGR valve lift.The built-in rotor of the step motor rotates in the normal or reverse direction by an incremental angle ●

according to the signal transmitted from the ECM to the stator coil. The EGR valve moves upward or downward by the amount of the rotor rotation, the ECM drives the step motor so that the actual step position of the step motor can follow the target step position.

Circuit<3<


Microprocessor

ECM

EGR Valve

MAIN12 V

MREL

EG+A

EG-A

EG+B

EG-B

E1

Battery

Drive Circuit

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Step Motor Movement: ■The 2-phase excitation drive method is used to operate the step motor. ●

While the 1-phase excitation rotates the rotor by energizing a coil phase-by-phase, the 2-phase ●

excitation energizes a coil two-by-two, increasing the torque that rotates the rotor. In accordance with the engine operating conditions, the ECM controls the step motor with a 2-phase ●

excitation. The step motor is controlled in up to 58 incremental steps, with a stroke of 4.3mm between the full close to full open positions.

2-Phase Excitation

Coil

Coil

Rotational Amount

Energized

Not Energized

Rotor (magnet)

Rotor (magnet)

S1

S2

S3

S4


Direction

Energized

Close Open


Equivalent Circuit

Rotor

S1

B1

S3

S2 B2 S4

S2 S1

B2 B1

S4 S3

TIP

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EGR Step Open and close EGR valve:From 0 to 125 steps


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Linear solenoid[[[

Description<1< The linear solenoid is used to open and close the EGR valve. The EGR valve system driven by the ●

linear solenoid consists of a solenoid (coil, spring and plunger), a valve that is coaxially coupled to the plunger, and the ECM that controls the solenoid. Compared to the EGR valve system which is driven by the vacuum actuator, the EGR volume can be regulated with a higher responsiveness and higher accuracy.In accordance with the engine operating conditions, the ECM calculates the current (duty signal) that ●

drives the linear solenoid and then applies it to the solenoid, regulating the valve lift. By receiving the valve position signal from the EGR valve lift sensor, the feedback control is conducted.

EGR Valve

Dual-Valve


Exhaust Gas OUT(To Intake Manifold)


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Operation<2< The plunger of the linear solenoid is being pushed toward the valve close direction by the spring, ●

however, when the coil is energized, the plunger moves to the valve open direction. The EGR valve lift is regulated by the balance between the spring force and the magnetic energy of the coil corresponding to the energization current (duty ratio). When the EGR valve needs to be opened, the ECM boosts the current (duty signal) applied to the linear solenoid, conversely, when the valve needs to be closed, the ECM decreases the current.

Circuit<3<

Linear Solenoid Drive Circuit(1)

Microprocessor

ECM

EGR ValveMAIN

12 V

12 V

MREL

EGRS

E1

Battery

Drive Circuit



Control the EGR Step Position Control the EGR valve position:0 to 100%

Control the EGR Step Position #2 Control the EGR valve (bank 2):0 to 100%


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DC motor Drive[5[

Description<1< The DC motor is used to open and close the EGR valve. The EGR valve system driven by the DC ●

motor consists of a DC motor, a valve, and the ECM that controls the DC motor. By using the DC motor for the EGR valve operation, a control with more torque, more sophisticated functions, and larger flow amount can be possible compared to the EGR valve system which is driven by the linear solenoid.The motor is driven by the request signal from the ECM. The valve lift is constantly monitored with ●

the EGR valve lift sensor, and the valve lift feedback control is conducted so that the valve lift can be appropriate to the engine operating conditions.

EGR ValveExhaust Gas OUT

(To Intake Manifold)


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Operation<2< The ECM calculates the required EGR valve lift appropriate to the engine operating conditions, and ●

drives the DC motor through the current control; the direction in which the current flows, and the magnitude of the flowing current. When the valve needs to be opened, the current is applied to the M+ and M- terminals as the motor positive pole and negative pole. Conversely, when the valve needs to be closed, the current is applied to the M+ and M- terminals by interchanging the positive and negative.The rotation of the DC motor opens and closes the EGR valve via the reduction gear provided on the ●

motor, regulating the amount of the EGR gas flow.

Circuit<3<


Microprocessor

ECM

EGR Valve(DC Motor)

12 V

EGM+

EGM-

Shield

M

Drive Circuit

Current Monitor

Character<[<



Control the EGR Step Position Control the EGR valve position:0 to 100%


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EGR Cooler Bypass Valve71

Description[1[ The EGR cooler bypass valve is fitted on the outlet port of the water-cooled EGR cooler, and ●

optimizes the temperature of the EGR gas that is recirculated into the intake passage, improving the exhaust gas purification performance since engine start.When the engine is cold or the engine load is low, if the compression heat in the engine compression ●

stroke is determined insufficient due to the low intake air temperature, the ECM closes the bypass valve and recirculates the EGR gas bypassing the EGR cooler into the intake air passage.This system consists of a bypass passage-equipped EGR cooler, a bypass valve, a vacuum actuator, ●

a vacuum switching valve (VSV), and the ECM that controls the vacuum switching valve.

EGR GasEGR Gas

EGR CoolerBypass Switching Valve

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Operation[2[ While the ignition switch is ON, the battery voltage is constantly supplied to the vacuum switching ●

valve (VSV) that switches the vacuum of the vacuum actuator. The ECM controls the VSV by switching the ground circuit of the VSV.According to the engine operating conditions, the ECM operates the VSV to activate the vacuum ●

actuator linked with the EGR cooler bypass valve, switching the EGR gas flow to either the EGR cooler or the EGR cooler bypass passage.

Circuit[3[

EGR Cooler Bypass Valve Circuit<1<

Microprocessor

ECM

VSV for EGR Cooler Bypass

Valve

12 V

MREL

E1

ECBVDiode *

MAIN

Battery

Drive Circuit

Drive Circuit


* A diode and fail detection circuit are applied depending on the type of vehicle.

Drive Voltage<2<


ECBVVSV Control OutputNormal

(Cold engine, Idling) 1.5 V or less

Normal(Engine warmed up, 3000 rpm) 12 V

ECBV circuit open Remains 12VECBV circuit GND short Remains 0 V

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Diesel Throttle81

Outline of Diesel Throttle[1[ The diesel throttle is a throttle valve that is driven by a motor or vacuum. By limiting the intake air ●

through use of the throttle valve, the intake manifold pressure is reduced, letting a large amount of the EGR gas enter. The diesel throttle can also be effective for the air-fuel ratio control as well as smooth engine stop.The diesel throttle is divided into four types depending on the throttle valve drive systems. ●

EGR Cooler EGR Valve


Intercooler

TypeStep motor Rotary Solenoid Drive DC motor1CD-FTVKD Series

AD SeriesKD Series

AD Series(for New Avensis)

Throttle Valve Drive system Step Motor Rotary Solenoid DC Motor

Throttle valve angle Controlled by the ECM directly.



Throttle Valve position detection


Throttle Position Sensor(no-contact type)

Throttle Position Sensor(no-contact type)


Equipped(Built into Diesel Throttle

Body)None None

In some 1ND-TV engines, a diesel throttle that is driven by a vacuum actuator and a VRV was used.

TIP

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Step Motor Drive[2[

Description<1< The step motor is used to open and close the throttle valve. The diesel throttle body consists of a step ●

motor (stator core and rotor), a throttle valve, and a throttle valve fully opened switch.The ECM monitors the engine operating conditions using the various sensors, and calculates the ●

number of directive steps. Based on the calculation, the ECM energizes the step motor. The motor rotates a number of degrees according to the number of directive steps, opening or closing the throttle valve.

Magnet

Reduction Gears

Throttle Control Motor

Rotor Shaft

Throttle Valve


Operations<2< The battery voltage is applied to the coil built into the step motor while the engine is running, and the ●

ground side of the coil is connected to the ECM. The ECM operates the step motor in incremental steps by switching the coil ground, to regulate the diesel throttle valve angle.The built-in rotor of the step motor rotates in the normal or reverse direction by an incremental angle ●

according to the signal transmitted from the ECM to the stator coil. The throttle valve opens or closes by the angle determined by the motor input speed that is reduced by the drive gear, the ECM drives the step motor so that the actual step position of the step motor can follow the target step position.

Relationship between the number of steps and opening angle

Full open switch ON

The number of steps

Small Full open 90˚

LargeFull close 7˚

2-phase excitationDrive 0.8˚

1-2 phase excitationDrive 0.4˚

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Step Motor Movement: ■The 1-2 phase excitation drive method and the 2-phase excitation drive method are used to operate ●

the step motor.While the 1-phase excitation rotates the rotor by energizing a coil phase-by-phase, the 2-phase ●

excitation energizes a coil two-by-two, increasing the torque that rotates the rotor. The 1-2 phase excitation can halve the amount of rotor rotation per energization by alternating the 1-phase and 2-phase excitations.In accordance with the engine operating conditions, the ECM accurately controls the step motor ●

with the 1-2 phase excitation or the 2-phase excitation. The step motor is controlled in up to 209 incremental steps (104 steps if only 2-phase excitation), and the throttle valve is controlled in an operating angle range of 83°(full close at 7°and full open at 90°).

2-Phase ExcitationCoil

Coil

Coil

Coil

Rotational Amount

Rotational Amount

Energized

Not Energized

Rotor (magnet)

Rotor (magnet)

Rotor (magnet)

Rotor (magnet)

1-2 Phase Excitation


: Energized

2-Phase Excitation1-2 Phase Excitation

Direction Close Open


Equivalent Circuit

Rotor

S1

B1

S3

S2 B2 S4

S2

S1

S2

S3

S4

S1

B2 B1

S4 S3

TIP

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Circuit<3<


Microprocessor

ECM


MAIN12 V

MREL

LU+A

LU-A

LU+B

LU-B

E1

Battery

Drive Circuit

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Rotary Solenoid Drive[3[

Description<1< In the rotary solenoid type diesel throttle system, a rotary solenoid is used to open and close the ●

throttle valve. The rotary solenoid type diesel throttle consists of a rotary solenoid (coil and magnet), a throttle valve, and a throttle valve position sensor.In accordance with the engine operating conditions, the ECM calculates the duty signal that drives ●

the rotary solenoid, regulating the throttle valve angle. The ECM performs the throttle valve angle feedback control according to the valve angle signals transmitted by the throttle position sensor.In order to minimize the vibration that occurs when the engine stops, the throttle valve fully closes ●

when the ignition switch is turned off, and then will fully open again for the next engine start.


Throttle Position Sensor

Rotary SolenoidThrottle Valve

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Operations<2< The rotary solenoid type throttle body energizes the solenoid (coil) using the built-in drive circuit ●

according to the duty signals transmitted by the ECM to rotate the rotor, regulating the throttle valve that coaxially operates with the rotor.

Circuit<3<

Rotary Solenoid Drive Circuit(1) The drive circuit and rotary solenoid, which are built into the diesel throttle body, have their own power ●

supply (+B) and ground (GND).

Microprocessor

ECMDiesel Throttle Body

12 V

MREL

LUSL

MAIN

Battery

Magnet

Solenoid Coil

Drive Circuit

Drive Circuit


Drive IC



Diesel Throttle Target Angle Control the diesel throttle valve (bank 1):0 to 90%

Diesel Throttle Target Angle #2 Control the diesel throttle valve (bank 2):0 to 90%


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DC motor Drive[[[

Description<1< The DC motor is used to open and close the throttle valve. The diesel throttle valve system driven by ●

the DC motor consists of a DC motor, a valve, and the ECM that controls the DC motor.The motor is driven by the request signal from the ECM. The valve angle is constantly monitored with ●

the throttle position sensor, and the valve angle feedback control is conducted so that the valve angle can be appropriate to the engine operating conditions.

DC Motor

Throttle Valve



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Operation<2< The ECM calculates the required throttle valve angle appropriate to the engine operating conditions, ●

and drives the DC motor through the current control; the direction in which the current flows, and the magnitude of the flowing current. When the valve needs to be opened, the current is applied to the M+ and M- terminals as the motor positive pole and negative pole. Conversely, when the valve needs to be closed, the current is applied to the M+ and M- terminals by interchanging the positive and negative.The rotation of the DC motor opens and closes the throttle valve via the reduction gear provided on ●

the motor, regulating the amount of intake air (intake manifold pressure).

Circuit<3<


Microprocessor

ECM

Throttle Control Motor (DC Motor)

12 V+BM

M+

M-

GE01

ME01

Shielded

M

Drive Circuit

Current Monitor



Diesel Throttle Target Angle Control the diesel throttle valve (bank 1):0 to 90%


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6 Control

6 Control8

Fuel Pressure Control (Common-rail Pressure)11

Description[1[ In common rail diesel engines, a stable injection pressure can be obtained even at a low speed ●

without being affected by the engine speed and load by storing high pressure fuel, which is fed from the supply pump, in the common rail. The ECM constantly monitors the common-rail pressure, and controls the supply pump SCV and feeds the fuel to allow the common-rail pressure to maintain the target pressure.

Engine ECU

ECU

Supply Pump

Fuel Filter

SCV

Fuel Temp. Sensor

Injector

Fuel Pressure Sensor Pressure Limiter

Fuel Tank

Common-Rail

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Component Parts and Functions[2[

ECM

Final Injection Volume




Component Function and PurposeCrankshaft Position Sensor Used to calculate the basic target common-rail pressure.Fuel Pressure Sensor Used to calculate the fuel pressure feedback volume.

Suction Control Valve Driven by the ECM and regulates the amount of fuel that is taken into the plunger chamber of the supply pump.

ECM

Calculates the basic common-rail pressure. Apply correction to basic target common-rail pressure and calculates the final target common-rail pressure. Controls the SCV based on the final target common-rail pressure and the actual common-rail pressures, and adjusts the common-rail pressure.

Final injection volume

Calculated by the injection volume control and used to calculate the basic target common-rail pressure.

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6 Control

Control[3[

Outline<1< The ECM calculates the basic target common-rail pressure based on the final injection volume and ●

the engine speed. In order to meet the engine conditions, the final target common-rail pressure is calculated from the product of the correction coefficient obtained by the output values from the various sensors and the basic target common-rail pressure. The ECM calculates the SCV drive current value (duty ratio) to allow the actual common-rail pressure to be the target pressure and energizes the SCV, thus adjusting the common-rail pressure to the target pressure.



Engine Speed Signals

Injection Volume Control

Basic Target Common-rail

Pressure

Final Target Common-rail Pressure

Fuel Pressure Control

Suction Control Valve Drive Control (Supply Pump)

Deviation Calculation of the Actual Common-rail Pressure and the Target Common-rail Pressure

Fuel Pressure Feedback Volume Calculation

Correction Coefficient to

calculate the Final Target Common-rail

Pressure

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Calculation of basic target common-rail pressure<2< The ECM calculates the basic target common-rail pressure from the final injection volume, which is ●

calculated based on the accelerator opening degree and the engine speed. As shown in the following map of the basic target common-rail pressure, the more the final injection volume is and the higher the engine speed is, the higher the common-rail pressure is calculated.

Basic injection pressure map ■

135 MPa

70 ~ 90 MPa

120 ~ 130 MPa

100 ~ 120 MPa90 ~ 100 MPa

50 ~ 70 MPa

30 ~ 50 MPa

Engine speed (rpm)

Fina

l inj

ectio

n vo

lum

e

1000 2000 3000 4000 50000

20

40

60

80

Drive of Suction Control Valve<3< The ECM calculates the SCV drive duty ratio to allow the actual common-rail pressure reach the ●

target pressure. The higher the target common-rail pressure is, the larger the SCV drive duty ratio is, whereas the lower the target common-rail pressure is, the smaller the SCV drive duty ratio is.

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6 Control

Injection Volume Control21

Description[1[ In the common-rail diesel engine, the ECM calculates two values: a basic injection volume and a ●

maximum injection volume, in accordance with the engine operating conditions. The ECM then compares the basic and maximum injection volumes and determines a smaller calculated value for the final injection volume.

Basic Injection Volume

Maximum Injection Volume

Comparison

Fuel Pressure Compensation Valve

Decision on Duration

Injector Feed Back Valve

EDU

InjectorECM

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Accelerator Pedal Position Sensor

Turbo Pressure Sensor

Atmospheric Temp. Sensor

Fuel Temp.

Mass Air Flow Meter

EDU

ECM

Injector

Vehicle Speed Signal


Intake Air Temp. Sensor


Engine Coolant Temp. Sensor

Starter Signal

Clutch Switch

Atmospheric Pressure Sensor

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6 Control

Component (Signal) Function and PurposeAccelerator Pedal Position Sensor Used to calculate the basic injection volume.


Used to calculate the basic and maximum injection volumes.Used as a correction value to calculate the final injection volume.Used to calculate the basic injection volume at engine start.Used to detect fluctuations in the engine speed.

Turbo Pressure Sensor Used as a correction value to calculate the maximum injection volume.

Intake Air Temp. Sensor Used as a correction value to calculate the maximum injection volume.

Fuel Pressure Sensor Used as a correction value to calculate the final injection volume.

Engine Coolant Temp. SensorUsed as a correction value to calculate the maximum injection volume.Used to calculate the basic injection volume at engine start.

Starter Signal

Used as a correction value to calculate the fuel injection volume at engine start.Used as a calculation start reference signal for the fuel injection volume at engine start

Vehicle Speed Signal Used as ISC (Idle Speed Control) correction value for the basic injection volume.

Clutch SwitchNeutral Start Switch

Used as ISC (Idle Speed Control) correction value for the basic injection volume.

EDU Drives the injector upon receiving the injection command signal from the ECM

ECM

Calculates the basic and maximum injection volumes.Calculates the final injection volume from the basic and maximum injection volumes.Calculates the basic injection volume at start and the corrected injection volume at start. Calculates a presumed actual fuel injection volume from the fluctuation in the engine speed and corrects the final injection volume. Transmits a fuel injection signal to the EDU.

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Control[3[

Outline<1< The ECM calculates the basic injection volume, based on the fuel injection volume pattern obtained ●

by the accelerat or pedal opening degree and the engine speed. In addition, the ECM calculates the maximum fuel injection volume by applying various corrections in accordance with the engine conditions to the basic maximum injection volume calculated based on the engine speed.Either the basic or the maximum fuel injection volume, whichever is smaller, is selected and set as ●

the base of the final fuel injection volume. Corrections are then applied to the base, and the final fuel injection volume is calculated.In addition, the fuel injection volume is calculated based on the engine coolant temperature, engine ●

speed and starter ON time when the engine is started.

Accelerator opening degree

Engine speed

Basic Injection Volume

Basic Maximum Injection Volume

Calculation of EDU Drive

Timing

Engine Speed

Engine Speed

Inje

ctio

n Vo

lum

e

Inje

ctio

n Vo

lum

e

Manifold Absolute ●Pressure CorrectionIntake Air Temperature ●CorrectionMaximum Fuel Injection ●Correction when the Engine is Cold.

Fuel Injection ●Volume Correction for Each CylinderSpeed Correction ●Fuel Injection ●Pressure Correction

Final Injection Volume after Correction

Smaller Volume of Fuel Injection

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Calculation of Basic Fuel Injection Volume<2< The ECM selects the fuel injection volume pattern according to signals (VPA) from the accelerator ●

pedal position sensor and signals (NE) from the crankshaft position sensor. The basic fuel injection volume is calculated by the selected pattern.In addition, idle speed control corrections from the clutch switch (park/neutral position switch) and ●

the vehicle speed signals, and the engine coolant temperature correction are applied to the basic fuel injection volume.

Basic Injection Volume Pattern ■

Engine Spped

#1 #2

#3 #4

#5

#6

#7

Bas

ic In

ject

ion

Volu

me

#1 Pattern 1: Below idling speed#2 Pattern 2: Idling speed#3 Pattern 3: Accelerator pedal depression degree of 10%#4 Pattern 4: Accelerator pedal depression degree of 20%#5 Pattern 5: Accelerator pedal depression degree of 30%#6 Pattern 6: Accelerator pedal depression degree of 50%#7 Pattern 7: Accelerator pedal depression degree of 100%

Pattern 7 of the injection volume in the maximum speed area is calculated considering the fuel injection volume reduction control that judges whether a driver dozes off or not while driving at high speeds for a long time.

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Calculation of Maximum Fuel Injection Volume<3< The maximum fuel injection volume is calculated by applying corrections such as manifold absolute ●

pressure correction, intake air temperature correction, fuel injection volume increase correction in cold start conditions to the basic maximum fuel injection volume which is determined in accordance with the engine speed.When the engine coolant temperature is 90 ˚C or more, the fuel injection volume is corrected to be ●

reduced. In addition, there are torque limit to protect drive systems, turbo speed limit to prevent the turbocharger from overrotating at high altitude, and intake air amount limit to prevent white smoke generation due to EGR cut delay, which are used to limit the injection volume within specified ranges.

[ Basic Injection Volume Pattern ]

Engine Spped

Intake Air Volume-small

Intake Air Volume-large

Varies by Required Volume

Bas

ic In

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Volu

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Calculation of Final Fuel Injection Volume<[< The ECM selects either the basic or the maximum fuel injection volume, whichever is smaller, and ●

then calculates the final fuel injection volume by applying corrections such as a fuel injection volume correction for each cylinder, engine speed correction and fuel injection pressure correction to the selected fuel injection volume.

[ Determining Injection Volume ]: Basic Injection Volume: Maximum Injection Volume

Engine Speed

30% VPA

Selects lowest

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Calculation formulaFinal fuel injection volume:

MIN (Basic and maximum fuel injection volumes) + Engine speed correction+ Fuel injection volume correction for each cylinder + Fuel injection pressure correction

The calculated final fuel injection volume is later used to calculate the fuel injection timing control, multiple injection control and EDU driving timing.

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Fuel Injection Volume at Engine Start<5< The fuel injection volume at engine start is calculated by applying a starter ON time correction to the ●

basic injection volume at engine start. The basic injection volume at engine start and increase and decrease rates of the fuel injection volume at engine start are calculated based on the engine coolant temperature and engine speed at engine start.

STA ON STA ONEngine start Engine start

STA ON time STA ON time

Basic fuel injection volume

HighEngine coolant temperature

Low

Fuel

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Fuel

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Various corrections<6< In order to obtain an optimal fuel injection volume in accordance with the engine operating conditions ●

requested by a driver, the final maximum fuel injection volume is calculated by applying corrections to the maximum fuel injection volume, based on the values from various sensors. The final fuel injection volume is calculated by applying corrections to the fuel injection volume which is selected from either the maximum or basic fuel injection volume.

Item Content

Reduction correction at high engine coolant temperature

Used to calculate the maximum fuel injection volume, and is used to protect the engine and injection systems at high engine coolant temperature.

Reduces the fuel injection volume by subtracting a predetermined correction value determined by the ECM from the maximum injection volume control value.

Increase correct ion af ter engine start in cold conditions

Used to calculate the maximum fuel injection volume.Ensures the start-off performance at extreme low temperature.

Applies correction values to the maximum injection volume control value and increases the fuel volume, to ensure a stable combustion after cold engine start.

[ Engine Coolant Correction ]

Engine Coolant Temperature (deg)

Increase

Correction Coefficient

1

40

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Item Content

Manifold absolute pressure correction

Intake air temperature correction

Used to calculate the maximum injection volume.

Corrects the combustion difference which is caused by the intake air density.

[ Manifold absolute Pressure Correction ]

Manifold absolute Pressure Sensor Output (V)

Pressure Correction Overload Protection

Increase

Decrease


1

3

[ Intake Air Temperature Correction ]

Intake Air Temperature (deg)

Decrease


1

40

Item Contents

Engine speed correction

Used to calculate the final fuel injection volume.Smoothes the fluctuation in the engine speed during acceleration and deceleration to improve drivability. Performs both the feedforward and feedback controls.

Fuel injection volume correction for each cylinder(Crank Time Compensation Learning)

Used to calculate the final fuel injection volume.Detects any fluctuation in the rotation of the cylinders while idling and increases and decreases the fuel injection volume for each cylinder, in order to reduce engine vibration caused by variations in the fuel injection volume for each cylinder.

Fuel injection pressure correctionUsed to calculate the final injection volume.Corrects the difference in the fuel injection volume according to the fuel pressure.

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REFERENCE

Accelerator pedal opening degree to calculate the fuel injection volume ■Torque control for the cruise control and the VSC are controlled by virtually changing the accelerator ●

opening degree to calculate the fuel injection volume. The fail-safe torque limit, such as when there is a malfunction in the system parts, is performed by limiting the accelerator opening degree to calculate the injection volume.The accelerator pedal opening degree to calculate the fuel injection volume can be checked by the item ●

“Accel. Position” on the data list.When there are no requests from the cruise control, ETC, or VSC system, or when the acceleration is ●

not limited by the fail-safe, the “Accel. Position” value varies in proportion to the accelerator depression amount.If the “Accel. Position” value ranges between 10 and 25% when the MIL illuminates and the accelerator ●

is fully opened, the acceleration is limited (engine output is limited) by the fail-safe.When the voltage applied to the accelerator is in a normal range (Accel Sensor Out No.1 and No.2), the ●

accelerator is limited (engine output is limited) by the fail-safe due to a malfunction in other actuators.

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Pilot Quantity Learning<7<

Outline of Pilot Quantity Learning(1) In recent common-rail injection systems, the fuel injection pressure is being progressively increased ●

to meet engine’s high power output and emission regulations. On the negative side, the fuel injection volume per valve opening time increases under high-pressure injection conditions, therefore, the variation in the fuel injection accuracy for each cylinder (variations in the injector open valve accuracy) causes a big difference in the fuel injection volume.In order to correct differences in the engines (fuel injection systems) and variations in the fuel injection ●

accuracy for each cylinder, a small amount of fuel is injected at the request of the ECM while the fuel is not injected for the output control during deceleration, and the actual fuel injection volume from the injector is estimated based on the fluctuation in the engine speed corresponding to the fuel injection. The ECM learns the difference between the estimated actual injection volume value and commanded very small injection volume value and then corrects the actual injection volume, thus equalizing the fuel injection volume for each cylinder.

Learning Process(2) When the ECM determines a decrease in the engine speed (vehicle speed) which meets a ●

predetermined condition, a small amount of fuel is injected once and the pulse width for the injection signal and the fluctuation (angular speed) in the engine speed are detected. The fluctuation in the engine speed is once converted into torque and then the torque is converted in the fuel injection volume. The ECM learns the difference between the converted fuel injection volume and the actual fuel injection volume and applies corrections to each cylinder injection volume.The small injection volume correction control has 2 modes: automatic mode in which the control is ●

performed while the vehicle is running, and manual mode in which the control is performed using an intelligent tester.

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Control Flow ■Determination of

prerequisite conditionsInjection of a very

small amount of fuel

Detection of fluctuation in the engine speed

due to injection, and processing of a

detected value

Application of correction volume

Engine speed

Injection volume Q

Q=0

TimeDetermined

CR

Injection volume Q

Q=0

TimeInjected

Engine speed

Injection volume Q

Q=0

Injected Injection pulse width

Q

Target QINJ Actual INJ

Map value

τ1 τ2τ

The ECM determines whethe r t he eng ine meets a predetermined condition to inject a very small volume of fuel, and then checks the in-jection point. *

The ECM determines which cylinder needs to be corrected, due to ei-ther variation in the fuel injection volume caused by deterioration in the cylinder over t ime or based on the previous fuel injection correction value (learned value), and determines the very small injection volume in accordance with the engine operating condi-tions. The fuel is inject-ed in a very short time dur ing decelerat ion, and the injection timing and pressure are de-termined in accordance with the engine operat-ing conditions.

The ECM detects fluc-tuation in the engine sp e e d (N E s i gna l s) when the very smal l volume of fuel is in -jected. The fluctuation in the engine speed is measured as crankshaft angular speed by the pulse width of NE sig-nals. The ECM converts the fluctuation in the en-gine speed into torque once, and inverse ly converts the torque into fuel injection volume. The ECM compares the very small fuel injec-t ion volume with the converted fuel injection volume, and learns the difference.

The dif ference between the actually injected very small fuel volume and the injection volume which is conver ted f rom the fluctuation in the engine speed is converted into a correction value to con-trol the injection volume, and reflected in the map value. The injection pulse width (Time: t1) for the fuel injection volume (Q) which is calculated from the map value under the injection volume control is corrected into the injection pulse width (t2) to obtain the actual fuel injection volume (Q).

*: The implementation conditions (prerequisite conditions) of the pilot quantity learning are outlined in the table below.

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Prerequisite conditions ■Conditions of pilot quantity learning (Auto mode)

When the ECD system works normally. ●After the engine is warmed up. (When the engine coolant temperature, intake air temperature and fuel ●temperature are within a predetermined range.)When the after-treatment is not controlled. (with DPF/DPNF catalytic converter) ●During deceleration from a speed above a predetermined speed and during the fuel cut-off operation. ●

Conditions of pilot quantity learning (Manual mode)When the ECD system works normally ●After the engine is warmed up. (The engine coolant temperature, air intake temperature and fuel ●temperature are within a predetermined range.)When the after-treatment is not controlled. (with DPF/DPNF catalytic converter) ●When the ignition switch is ON or while idling ●

The status of the pilot quantity learning can be checked by using data list on the intelligent tester. ●

Data List Item Confirmation ItemPilot Quantity State (CAT) Is the pilot quantity learning allowed on the system?

Pilot Quantity StateCurrent status of the pilot quantity learning

Is “Complete” (learning complete status) displayed?


Confirmation of Injection Volume: ■The fuel system can be easily inspected by checking the injection volume and the injection feedback ●

value, which are displayed on the data list.When there are significant variations in the fuel injection correction volume for each cylinder “injector ●

feedback value #”, there may be a malfunction in one or more of the cylinders. The fuel injection correction volume is used to correct the crankshaft angular speed for each cylinder. Therefore, it cannot specify that the cylinder of which the correction volume significantly deviates may be a malfunctioning cylinder, since the correction value may be increased or decreased to correct the malfunctioning cylinder.In addition, even when there are no extreme variations in the fuel injection correction volume for ●

each cylinder, if the “Injection Volume” on the data list is extremely high, there may be a malfunction in the fuel system relating to all the cylinders (including all injectors).

At this moment, the actual fuel injection volume from the injector cannot be detected and the feedback cannot be given. The fuel injection correction volume for each cylinder which is displayed using tools is corrected based on the angular speed at the time of the fuel injection from each cylinder which is detected from NE signals, therefore, some mechanical or electrical malfunctions may not be able to be reflected in the volume.

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Injection Timing Control31

Description[1[ In the common-rail diesel engine, the fuel injection timing control is performed by controlling the ●

injector opening timing, based on the main fuel injection timing obtained by applying corrections in accordance with the engine operating conditions to the basic fuel injection timing which is calculated by the ECM.

Basic Injection Timing

Injection Timing Correction

ECM

EDU

Injector

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EDU

Injector


ECM


Intake Air Temperature Sensor


Starter Signal

Component (Signal) Function and Purpose

Crankshaft Position SensorUsed to calculate the basic injection timing.Used to calculate the target fuel injection timing at engine start.

Turbo Pressure Sensor Used as a correction value of the basic injection timing.Intake Air Temp. Sensor Used as a correction value of the basic injection timing.

Engine Coolant Temp. SensorUsed as a correction value of the basic injection timing.Used to calculate the target fuel injection timing at engine start.

Starter Signal Used as a calculation start reference signal of the target fuel injection timing at engine start.

EDU Drives the injector upon receipt of the injection command signal from the ECM.

ECM

Calculates the basic injection timing.Applies corrections to the basic injection timing and calculates the main injection timing.Transmits an injection command signal to the EDU.

Final Injection Volume Calculated by the injection volume control and is used to calculate the basic injection timing.

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Control[3[

Outline<1< The ECM calculates the basic injection timing based on the engine speed (NE pulse) and the final ●

injection volume, and then applies various kinds of corrections to it, thus determining the optimal main target injection timing.

Basic Injection Timing

Engine Speed


Main Injection TimingCorrections

Pilot Interval

TDC

0 1

Main Injection Timing

Pilot Injection Timing

Injector Drive Pluse

NE Pulse

Nozzle Needle Lift

(2) Injection timing calculation method

(1) Outline of control timing

Pilot InjectionMain Injection

Engine Coolant Temperature Correction ●Intake Air Temperature Correction ●Manifold Absolute Pressure Correction ●

Calculation of Basic Injection Timing<2< The ECM calculates the basic injection timing, based on the final injection volume calculated by the ●

injection volume control and signal (NE) from the crankshaft position sensor. (Map calculation)

BTDC

TDC

ATDC

Engine Speed (rpm)

Inje

ctio

n Ti

min

g (˚C

A)

30 mm3/st60 mm3/st

10 mm3/st

20

10

0

-10

1000 2000 3000 4000

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Calculation of Main Injection Timing<3< The ECM calculates the main injection timing by applying corrections such as the intake pressure ●

correction, cold correction, intake air temperature correction and load correction to the basic injection timing.

Calculation formulaMain injection timing:{[Basic injection timing - (Manifold absolute pressure correction + Cold correction + Intake air temperature correction x Load correction] - Advance after cold start} + retard at high engine coolant temperature

Calculation of Main Injection Timing at Engine Start<[< The ECM calculates the main injection timing at engine start, based on the engine coolant ●

temperature and the engine speed. (Map calculation)

Injection Timing (˚CA)

TDC

Low

Low

High

High1000

Retard

Advance

Engine Coolant Temperature

Engine Speed (rpm)

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Various corrections<5< In order to obtain an optimal injection timing in accordance with the engine operating conditions, the ●

main injection timing is calculated by applying corrections to the basic injection timing and the basic pilot interval based on values from the various sensors.

Item Content

Manifold absolute pressure correction

Cold correction

Intake temperature correction

Load correction coefficient

Used to calculate the main injection timing.Used for environmental corrections for the engine operating conditions such as a misfire and white smoke.

[ Intake Air Pressure Correction ]

Manifold Absolute Pressure (MAP)

High rpmLow rpm

Timing Advance

(˚CA)

[ Water Temperature Correction ]

Engine Speed (rpm)

HotCold

Timing Advance

(˚CA)

[ Water Temperature Correction ]

Intake Air Temperature (deg)

1

40


Decrease

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Item Content

Advance correction after cold start

Used to calculate the main injection timing.Used for countermeasures against misfire and white smoke immediately after engine start.

In order to ensure the combustion stability after cold start, advance the injection timing by applying the correction value to the injection timing control value.

Retard at high coolant temperature

Used to calculate the main injection timing and reduce the thermal loads at high temperature

Retards the injection timing by subtracting a predetermined correction value calculated by the ECM from the injection timing control value.

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Multiple Injection Control[1

Description[1[ The multiple injection control, in which the fuel is injected separately in multiple times (Max.: 5 times) ●

per cycle, improves fuel combustion in the main injection by injecting a small amount of fuel before and after the main injection.Aside from the pilot injection (pilot 1), pre-injection (pilot 2), main injection and after injection which ●

are related to combustion (engine output control), the post injection, which is used for exhaust gas treatment for engines equipped with DPF or DPNR that is not related to combustion (engine output control), is provided. Thus, there are 5 types of injection in the multiple injection control.

Inje

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Time

Pilot Injection(Pilot 1)

Pre Injection(Pilot 2)

Main Injection

After Injection

Post Injection

Multiple Injection ■Pilot Injection(Pilot 1)

By injecting fuel before the ˚CA (crankshaft angle) becomes 20° against the main injection, pre-mixture of air and fuel is performed and the air utilization rate in the combustion is enhanced, thus reducing smoke emissions and improving the engine torque.

Pre Injection(Pilot 2)

By injecting a small amount of fuel immediately before the main injection, the ignition performance in the main injection is ensured. In addition, by smoothly increasing the combustion pressure due to the combustion, the combustion noise and HC emissions can be reduced.

Main Injection Main fuel injection to obtain the engine output.

After InjectionBy injecting a small amount of fuel immediately after the main injection and accelerating the combustion reaction for unburnt residue, smoke emissions are reduced and the catalyst is activated in accordance with the increase in the exhaust gas temperature.

Post InjectionIn the latter half of the expansion process after the main injection, a small amount of fuel is injected. This is used for the after-treatment control on engines equipped with DPF or DPNR.

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EDU

Injector


ECM


Intake Air Temperature Sensor


Starter Signal



Used to calculate the multiple injection modes. Used to calculate each injection volume and interval for the multiple injections.Used as a correction value to calculate the pilot/pre-injection volumes at engine start.Used to calculate the pilot/pre injection timings at engine start.

Turbo Pressure Sensor Used as a correction value to calculate the pilot/pre-injection volumes.Intake Air Temp. Sensor Used as a correction value to calculate the pilot intervals 1 and 2.Atmospheric Pressure Sensor Used as a correction value to calculate the pilot intervals 1 and 2.


Used as a correction value to calculate the pilot/pre injection volumes.Used to calculate the basic pilot/pre injection volumes at engine start. Used as a correction value to calculate the pilot intervals 1 and 2. Used to calculate the pilot/pre injection timings at engine start.

Starter Signal Used as a calculation start reference signal for the pilot/pre injection volumes and timing at engine start.

EDU Drives the injector upon receiving the injection command signal from the ECM.

ECM

Calculates the multiple injection modes.Calculates each injection volume and interval for the multiple injections. Calculates the basic pilot/pre injection volumes at engine start and corrected pilot/pre injection volumes at engine start. Calculates the pilot/pre injection timings at engine start. Transmits injection command signals to the EDU.


Calculated by the injection volume control and is used to calculate the multiple injection modes and each injection volume and interval for the multiple injections.

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Control[3[

Outline of Multiple Injection Control<1<

Injection Mode(1) The multiple injection control has 5 patterns of injection mode (and post injection mode for after- ●

treatment control) described in the table below. The ECM performs injection by switching the injection mode to obtain an optimal combustion in accordance with the engine operating conditions. The injection mode is calculated and selected based on the final injection volume by the injection volume control and engine speed signals (NE). Each injection volume and interval for the multiple injections are simultaneously calculated and controlled from the map.

Distribution of multiple injection modes ■


Engine Speed1

4 5

3

2

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Multiple injection modes ■Mode Injection pattern

Mode 1 No injection

Mode 2

Main injection only:The injection volume is not divided.

Mode 3

Pre-injection (pilot 2) + Main injectionThe injection volume is divided and the pilot intervals 1, 2 are calculated, at the same time.

Mode 4

Pilot injection (pilot 1) + Pre-injection (pilot 2) + Main injection:The injection volume is divided and the pilot intervals 1, 2 are calculated at the same time.

Mode 5

Pilot injection (pilot 1) + Pre-injection (pilot 2) + Main injection + After injection:The fuel injection volume is divided and the pilot intervals 1, 2 and after interval are calculated at the same time.

Post inject ion for a f ter - t reatment control

Any mode of the above-described modes: 2 to 5 + Post injection*Additional control of the above multiple injection control and injection for after-treatment control are performed.

* The injection volume and interval in the post injection mode are separately calculated by the after-treatment (control/system).

Example of Injection Volume Rate(2) The multiple injection volume control is a control that calculates the injection mode, division of ●

the final injection volume and injection interval from each map based on the final injection volume calculated by the injection volume control and the engine speed and then applies corrections to them. The injection mode, injection volume rate and interval are simultaneously determined, and then integrated and output for injector drive calculation. The multiple injection control is performed by selecting various injection combinations in accordance with the engine conditions.

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Reference example of calculation ■Change in the injection rate in accordance with change in the engine speed at the final injection volume of 25mm3/st.

Injection mode

Final injection volume ≈ A+B+C+D (Corrections excluded)Main injection volume ≈ Final injection volume – (A+B+D) (Corrections excluded)

Injection volume A Injection volume B Injection volume C Injection volume D

Engine speed Pilot injection(Pilot 1)

Pre-injection(Pilot 2) Main injection After injection

800 2.0 4.0 19.0 0.01200 2.0 2.8 20.2 0.01600 2.0 2.0 19.0 2.02000 2.0 4.0 17.0 2.02400 2.0 4.0 19.0 0.02800 0.0 4.0 21.0 0.03200 0.0 4.0 21.0 0.03600 0.0 1.2 23.8 0.04000 0.0 0.0 25.0 0.0

Multiple Injection Volume<2<

Outline(1) Necessary injection type is selected from the pilot, pre or after injections, with the final injection ●

volume which is calculated by the injection volume control set as the total injection volume, and the fuel injection volume is divided at an appropriate rate.

Flow of the multiple injection control calculation ■


Calculation of EDU Drive Signals

Simultaneous calculation of the injection mode, volume and interval (Map calculation)

Multiple Injection Control

Engine Speed Signals (NE)

Injection Volume

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Calculation of Pilot and Pre-injection Volumes(2) When the multiple injection control modes: mode 3, 4 and 5 are selected, the pilot injection volume ●

and/or the pre injection volume are/is calculated.The pilot injection volume (pilot 1) and the pre-injection volume (pilot 2) are calculated by applying the ●

cold correction and boost pressure correction to the basic pilot injection volume and the basic pre-injection volume. The basic pilot injection volume and the basic pre injection volume are obtained based on the final injection volume and the engine speed signals (NE) which are calculated by the injection volume control. (Map calculation)The pilot injection volume and pre-injection volume at engine start are calculated by applying the ●

engine speed correction to the basic pilot injection volume and the basic pre-injection volume which are calculated by the engine coolant temperature.

Calculation of After Injection Volume(3) The after injection volume is calculated based on the final injection volume calculated by the injection ●

volume control and engine speed signals (NE) when the multiple injection control mode 5 is selected. (Map calculation)

Calculation of Main Injection Volume([) After the multiple injection control mode is determined, the main injection volume is calculated by ●

subtracting the total injection volume of the required multiple injection from the pilot, pre, or after injection, from the final injection volume (total injection volume) which is calculated by the injection volume control, to which the torque correction is applied.

The multiple injection control is a control that divides the total injection volume. Therefore, the total volume of the pilot, pre, main and after injection approximately almost equals to the final injection volume. (Corrections excluded).

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Multiple Injection Timing<3<

Outline(1) When the multiple injection control modes: 3, 4 and 5 are selected, necessary multiple injection ●

timings other than the main injection are calculated in accordance with the mode. The injection timings are individually calculated as follows: the pilot interval 1 for the pilot injection (pilot 1), the pilot interval 2 for the pre injection (pilot 2) and after interval for the after injection. Then, fuel is injected at the timing when the calculated intervals are added to the main injection timing.The pilot interval 1, pilot interval 2 and after interval are calculated based on the final injection volume, ●

engine speed, engine coolant temperature and atmospheric pressure (Map correction). However, at engine start, the intervals are calculated based on the engine coolant temperature and the engine speed.

Pilot Interval 1

Pilot Interval 2

Main injection timing

After Interval

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Time

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Calculation of Pilot and Pre Injection Timings(2) The pre injection timing and the pilot injection timing are calculated when the particular mode is ●

selected by the multiple injection control.The pre-injection timing is calculated by adding the pilot interval 2, which is calculated by applying the ●

most minimum value of the engine coolant temperature correction, intake air temperature correction and atmospheric pressure correction and load corrections to the basic pilot interval 2 calculated based on the engine speed and the final injection volume, to the main injection timing in the advance direction.Similarly with the above case, the pilot injection timing is calculated by adding the basic interval 1 to ●

which corrections applied, to the pre injection timing in the advance direction.The pilot injection timing at start and the pre injection timing at start are calculated based on the ●

engine coolant temperature and the engine speed when the engine is started,

Basic pilot injection interval map ■60mm3/set

Engine Speed (rpm)

Inte

rval

(˚C

A)

30mm3/set10mm3/set

50

40

30

20

1000 2000 3000

Calculation of After Injection Timing(3) The after interval is calculated based on the final injection volume which is calculated by the injection ●

volume control and engine speed signals (NE) when the after injection is selected by the multiple injection control. (Map calculation) The after injection timing is calculated by adding the after interval to the main injection timing in the retard direction.

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Various Corrections<[< In order to obtain the optimal combustion in accordance with the engine operating conditions, the ●

multiple injection volume control is performed by correcting the basic injection volume and the basic pilot interval based on values from the various sensors.

Item ContentCold correctionBoost pressure correction

Used to calculate the pilot injection volume and the pre-injection volume.

Engine speed correction Used to calculate the pilot injection volume and pre-injection volume at engine start.

Torque correction Used to calculate the main injection volume.Smoothes the transition of switching the multiple injection mode.

Engine Coolant temperature correctionIntake air temperature correctionAtmospheric pressure correctionLoad correction coefficient

Used to calculate the pilot intervals 1 and 2.

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Glow Control51

Description[1[ The glow control is a control that raises the compressed air temperature by operating the glow ●

plug at cold engine start and heating the air in the combustion chamber, thus improving the engine startability.After the engine is started, the ECM performs an after-glow for a certain period of time. The after- ●

glow reduces diesel knock, white smoke emissions and engine noises when the engine is cold.


Engine Coolant Temperature Sensor Glow Relay

Glow Plug

Glow Indicator Light

ECM

Starter Signal


Engine Coolant Temp. SensorUsed to calculate the pre-heating and after-glow control time. Used to calculate the glow indicator light illumination time.

Starter SignalUsed as a reference signal of after-glow control start.Used as a reference signal of the glow indicator light off.

Glow Relay Supplies power to the glow plug. Glow Indicator Light Informs the user of the pre-heating control status.

ECMCalculates the pre-heating and after-glow control time. Turns the glow relay contact on/off. Controls the glow indicator light illumination.

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Control[3[

Outline<1< The ECM controls the glow plug operation by turning the power supply of the glow relay on/off. ●

The glow control has two kinds of control patterns: a pre-heating control when the ignition switch is on ●

before engine start, and an after-glow control while cranking and after engine start. Basically, the glow relay is turned on under the following conditions: while the ignition switch is on and the pre-heating is being enacted; while cranking; and while the after-glow control is being performed.The ECM also performs the glow indicator light illumination control that informs the user of that the ●

engine is ready to start when the combustion chamber is heated under the pre-heating control.

Conditions when the glow relay is on Control itemsWhen the ignition switch is turned off to on Pre-heating control

While crankingAfter-glow control

When STA is turned on to off, and when it is determined that the engine has started.

Glow control time chart ■IGS/W

ON

ON

Illumination

Pre-heating After-heating

OFF

OFFSTA

G-IND

S-REL

Vehicles equipped with DPNR are provided with a control that turns on the glow relay when the catalyst regeneration control is started and helps to increase the catalyst temperature, in addition to a control that performs pre-heating at engine start.

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Pre-heating Control<2< When the ignition switch is turned from off to on, the ECM controls the glow relay on time using two ●

kinds of energization patterns in accordance with the engine coolant temperature.

When the engine coolant temperature is 40 ˚C or higher(1) The ECM turns on the glow relay for 1 second after the ignition switch is turned on. ●

IG ON

ON

1 sec.OFF

When the engine coolant temperature is below 40 ˚C(2) The ECM turns the glow relay on/off repeatedly for at most 15 seconds after the ignition switch is ●

turned on (after energized). The glow relay on time is made to vary in accordance with the battery voltage.

IG ON

ON

OFF2 sec.

15 sec. at most

A

Battery voltage 11.5V 12V 12.5V 13V 13.5V 14VEnergization time A 15sec. 10.5sec. 8.4sec. 7.4sec. 6.8sec. 4.7sec.

After-glow Control<3< While cranking (while STA signal is input) or after engine start, the ECM performs the after-flow ●

control, keeping the glow relay on until the engine coolant temperature reaches to 40 ˚C or more. The energization time of the glow relay varies in accordance with the engine coolant temperature.

120

10 20 30 40 50Engine Coolant temperature (˚C)

Ener

giza

tion

dura

tion

(sec

)

1

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Glow Indicator Light Control<[< The ECM turns the glow indicator light on/off to inform the user of the pre-heating status under ●

the glow control after the ignition switch is turned to on. The glow indicator light turns on only for a predetermined time in accordance with the engine coolant temperature at engine start. However, the glow indicator light turns off when cranking occurs while it is turned on (when the STA signal is input).

-20 0 20 40Engine Coolant temperature (˚C)

Illum

inat

ion

dura

tion

(sec

)

2

4

6

Drive of Glow Relay and Glow Indicator Light<5< The ECM determines the pre-heating time and the timing of displaying the status that the engine ●

is ready to start (glow indicator light turn-off timing), mainly in accordance with the engine coolant temperature.The lower the engine coolant temperature is set, the longer the pre-heating time (glow energizing ●

time) is.

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After-Treatment Control (DPF)61

Description[1[ The DPF catalyst oxidizes CO and HC in the exhaust gas, and traps and oxidizes PM. ●

The PM, which is trapped by the DPF catalyst, will be oxidized by the DPF catalyst and the oxidation ●

catalytic converter (oxidation catalyst) located in front of the DPF catalytic converter while the exhaust gas temperature is high.If the DPF catalyst temperature remains low for an extended period so that the PM cannot be oxidized, ●

or if the vehicle has been driven for a certain period and the ECM determines that the amount of PM deposited on the DPF catalyst is higher than a certain amount, DPF catalyst regeneration control will be conducted by the ECM, burning the PM deposits.

Subsrate

Continuous Regeneration

PM

Pt

NO2 that is generated from NO, which was in the exhaust gas, through oxidation by the oxidation catalyst.

PM

DPF Temp. Up

Pt

Forcible Regeneration

Subsrate

Fuel that is added by the exhaust fuel addition injector.

Residual oxygen in the exhaust gas.

Catalyst Regeneration Flow ■Flow Continuous Regeneration Forcible Regeneration

1: Catalyst temperature rise

The temperatures of the oxidation and DPF catalysts rise in accordance with the increase in the exhaust temperature while driving.

The temperatures of the oxidation and DPF catalysts are forc ib ly increased by the combustion control.

2: PM treatmentPM is oxidized by the oxidation reaction that takes place when the temperatures of both catalysts rise.

In addit ion to the PM oxidat ion described to the left, by reacting the high-temperature DPF catalyst with the fuel added by the exhaust fuel addition injector, the temperature of the DPF catalyst is raised further, burning PM.

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Mass Air Flow Meter

Exhaust Gas Temp. Sensor

EDU

Injector

Exhaust Fuel Addition Injector

ECM



Air Fuel Ratio Sensor



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Accelerator Pedal Position Sensor Used to calculate the amount of fuel added and fuel addition timing for the catalyst regeneration control.

Crankshaft Position Sensor Used to calculate the amount of fuel added and fuel addition timing for the catalyst regeneration control.

Turbo Pressure Sensor Used to correct the amount of fuel added and fuel addition timing under the catalyst regeneration control.

Intake Air Temp. Sensor Used to correct the amount of fuel added and fuel addition timing under the catalyst regeneration control.

Engine Coolant Temp. Sensor Used to correct the amount of fuel added and fuel addition timing under the catalyst regeneration control.

Air Fuel Ratio Sensor Used to detect abnormality in the exhaust fuel addition injector.Mass Air Flow Meter Used to calculate the amount of PM deposited on the DPF catalyst.Differential Pressure Sensor Used to calculate the amount of PM deposited on the DPF catalyst.

Exhaust Gas Temp. Sensor Used to correct the amount of fuel added for the catalyst regeneration control.

Exhaust Fuel Addition Injector Adds fuel to the exhaust system.

Vehicle Speed Signal Used as a reference signal for starting the catalyst regeneration control.

EDU Drives the injectors when receiving injection request signals from the ECM.

ECM

Controls the catalyst regeneration control according to the sensor signals.Transmits injection request signals to the EDU and the exhaust fuel addition injector.

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Control[3[

Outline<1< Based on the vehicle driving conditions, intake air amount, and differential pressure sensor outputs, ●

the amount of PM which has been deposited on the DPF catalyst is calculated, and when the level of PM deposits exceeds a predetermined level, catalyst regeneration control is conducted.During catalyst regeneration, when the amount of residual PM estimated from the engine operating ●

conditions and the sensor signals, which are sent by the two exhaust gas temperature sensors fitted on the catalytic converter, is 0g, or when the differential pressure between the before and after the catalyst fall below a certain value, the catalyst regeneration control ends.The catalyst regeneration control (converter bed temperature rise) is performed via fuel addition, ●

where fuel is added to the exhaust system without affecting engine output, and combustion control, which increases the temperature of the exhaust gas emitted from the engine.Using the temperature rise multiple injection control , the DPF catalyst regeneration control raises the ●

converter bed temperature to a temperature where fuel can be added into the exhaust system, and then starts the exhaust fuel addition control, burning PM.During normal engine combustion, when it is determined that the DPF catalyst is clogged with PM, ●

the ECM increases the converter bed temperature to a temperature where fuel can be added into the exhaust system via the combustion control (temperature rise multiple injection). After that, fuel will be added into the exhaust system, and the converter bed temperature will rise to near 600 ˚C where PM can burn.

PM regeneration control flow

DPF catalytic converter bed temp.Amount of PM deposits

Normal combustion

Temp. rise multi-injection

Temp. rise multi-injection and Exhaust fuel addition

Normal combustion

1

2 3

4

1 Determination of PM clogging

2 Rises up to a temperature where exhaust fuel addition becomes possible

3 Maintained high through feedback control with exhaust gas temp. sensor

4 PM regeneration ends

REFERENCE The output of the exhaust gas temperature sensor will be 500 to 700˚C while the catalyst regeneration ●

control is being conducted. The ECM feeds the exhaust gas temperature sensor output into the catalyst regeneration control to prevent the catalyst temperature from rising too high due to the excessive PM deposits.

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Exhaust fuel addition<2< During the catalyst regeneration, a converter bed temperature rise is primarily performed by adding ●

fuel to the exhaust system.There are two types of fuel addition methods; one is that fuel is added in accordance with the ECM ●

injection signal via the exhaust fuel addition injector fitted on the exhaust port of the cylinder, the other is that a normal fuel injector performs a post fuel injection inside the cylinder (120-150˚ after the crankshaft compression TDC) in order to add fuel into the exhaust system.The fuel addition amount and timing used in the catalyst regeneration control are calculated in ●

accordance with the engine operating conditions such as the accelerator pedal position and engine speed, and are determined after the corrections from the engine coolant temperature, intake air temperature and manifold absolute pressure. Also, feedback control is conducted based on the exhaust gas temperature during the catalyst regeneration. During the catalyst regeneration, when the exhaust gas temperature is lower than the target, the ECM increases the correction value of calculated exhaust fuel addition amount, and conversely when it is higher, the ECM reduces the correction value.

Fuel addition by exhaust fuel addition ■

Supply Pump

Injector Spray


Fuel addition through post injection ■120-150 ˚CA

Time

TDC

Pilot injection

Pre-injection

After-injection

Post injectionFu

el In

ject

ion

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Combustion control<3< In addition to the exhaust fuel addition control, there are associated controls that support the catalyst ●

regeneration control for increasing catalyst temperatures.Combustion control ■

Control Description

Temperature rise multiple injection

With the same EGR rate and air-fuel ratio configurations as those of the usual combustion mode, post injection is performed in the exhaust stroke after the main injection. This control is conducted in order to raise the converter bed temperature up to a temperature where the converter bed temperature can be increased by the exhaust fuel addition during the catalyst regeneration control.

Exhaust reduction control and idle-up control

1KD-FTV engine for Japan (as of October 2008):The engine load is increased by closing the exhaust gas control valve provided after the catalyst, allowing the exhaust temperature to rise. Those controls are conducted to ensure the converter bed temperature rise and promptly complete it during the catalyst regeneration control.

Glow controlOn some vehicles with the catalyst regeneration control, the exhaust temperature is raised by energizing the glow plugs when the catalyst regeneration control begins.

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There are variations depending on the driving conditions, the catalyst regeneration control is ●

conducted every several hundred kilometers, and a 5-10km distance drive is necessary when the regeneration control is completed. Under normal driving conditions, the catalyst regeneration control is automatically conducted when PM has been deposited on the catalyst, so deposits and regeneration occur alternately. However, when the vehicle is successively driven for only short distance trips, the catalyst regeneration control may not be fully conducted.The catalyst regeneration control begins when the converter bed temperature is in the normal active ●

range (more than 200 ˚C) and it is determined that the catalyst is clogged after the engine has warmed up. If the vehicle is driven and the engine is turned off before the engine has fully warmed up, or the vehicle is successively driven for short distances in which the catalyst regeneration control is unable to be completed, PM will continue to be deposited on the catalyst.If the catalyst regeneration control is conducted when a large amount of PM has been deposited, ●

the heat developed by the PM combustion will exceed the catalyst heat-resistance range, and may cause the catalyst to melt. Thus, in order to prevent the catalyst from being damaged, the catalyst regeneration control will not be conducted either when the calculated value of deposited PM amount, or the signal output from the differential pressure sensor before and after the catalyst, indicates that the amount of PM deposits exceeds a predetermined level. However, if the catalyst regeneration control is conducted when the PM deposit amount is around the predetermined level, the catalyst may be seriously damaged due to heat deterioration.

Forcible PM regeneration control flow ■

Converter bed temperature (˚C)

Forcible regeneration control

Engine operating conditions Normal

Several hundred km

Forcible PM regeneration

5 to 10 km

Amount of PM deposits (g)

Vehicle speed

Travel distance

0

0

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Corrections<[< In order to raise the ● converter bed temperature according to the engine operation conditions, such as idling and driving, the amount of fuel added is determined from the outputs of the various sensors, and furthermore, a target converter bed temperature (exhaust gas temperature) is calculated after correction.

Item DescriptionEngine coolant temperature correctionIntake air temperature (behind the turbocharger) correctionManifold absolute pressure correction

Used to calculate the amount and timing of exhaust fuel addition.

Exhaust fuel addition amount correction value (Exhaust Fuel Addition FB)

Used to calculate the amount of exhaust fuel addition.During the catalyst regeneration, when the converter bed temperature (exhaust temperature) does not reach the target temperature, the correction value is increased, increasing the injection amount. When it is higher than the target temperature, the correction value is reduced, reducing the injection amount.

Differential pressure sensor correction value

Used to estimate the amount of PM deposited on the catalyst.The sensor output when the ignition switch is in the ON position (the engine is not started) will be the standard for no pressure difference. When the sensor is normal, the Data List item, Diff. Press. Sensor Corr., should be within the range of -1.5 to 1.5 kPa.

Air-fuel ratio sensor output signal

Used to detect abnormalities in the exhaust fuel addition injector. When the fuel is injected, the fuel injection conditions are monitored by referring to changes in the signal waveform of the air-fuel ratio sensor.Some vehicles, in order to obtain a more accurate, appropriate EGR rate, learn and correct the individual sensor output differences, and then store that value into the ECM.

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System Confirmation ■Through use of an Intelligent Tester, whether or not the after-treatment system is operating properly ●

can be checked by monitoring the following list items while the Active Test item, [Activate the DPF Rejuvenate (PM)], is performed; Exhaust gas temperature sensor output, AF Lambda B1S1, and Exhaust Fuel Addition FB.During the catalyst regeneration, the exhaust gas temperature value displayed in the Data List, ●

Exhaust Temperature, represents the conditions of the exhaust fuel addition and PM combustion, and AF Lambda B1S1 shows the actual air-fuel ratio based on the stoichiometric air-fuel ratio 14.5 to 1. Also, by looking at the exhaust fuel addition amount correction value (Exhaust Fuel Addition FB), to what degree the exhaust fuel addition amount, which is added by the exhaust fuel addition injector, has been corrected can be checked. The degree of how much PM has been deposited on the catalyst can be roughly estimated through the intake air amount (MAF) and catalyst differential pressure (DPF Differential Pressure).Checking the values will help when the after-treatment system is inspected. ●

Data List Item Diagnostic Note

Exhaust Temperature B1S1

Exhaust Temperature B1S2

Used to estimate the converter bed temperature (state of the temperature that is ●raised by adding the fuel) or determine the start timing of fuel addition through the sensor located before the catalytic converter. The converter bed temperature (PM combustion temperature) is determined through the sensor located after the catalytic converter. Usually, the sensor output will be 500 to 700 ˚C (reference values) while the catalyst regeneration control is being conducted.When the value of Exhaust Temperature B1S1 (before the catalytic converter) ●is abnormally high (more than 800 ˚C), it indicates that too much fuel has been added. It may be that the exhaust fuel addition injector has problems, or the ECM has requested more fuel injection than usual due to engine problems.When the value of Exhaust Temperature B1S1 (before the catalytic converter) ●is in the normal range and the value of B1S2 (after the catalytic converter) is abnormally high (more than 800 ˚C), it indicates that the heat generated inside the catalyst is high while the catalyst regeneration is performed. It is may be that a large amount of PM has been deposited on the DPF.Two or more problems described above may occur simultaneously. When the ●temperature before the catalytic converter is high, the sensor located after the catalytic converter is subject to send a high output.

AF Lambda B1S1

When the value is below 0.85, it is suspected that the air-fuel ratio sensor is malfunctioning, or the actual air-fuel ratio is abnormally rich. Furthermore, the exhaust fuel addition injection may have stuck open, or the engine itself has mechanical problems such as the EGR valve stuck open. Normally, the value will be 1.2 to 1.7 (reference values) while the catalyst regeneration control is being conducted.

Exhaust Fuel Addition FB

When the value is abnormally high or remains at its maximum value of 1.99, it is suspected that the converter bed temperature (exhaust gas temperature) during the catalyst regeneration has not reached the target temperature. Possible causes are; the actual exhaust fuel addition amount is low, or the catalyst itself is abnormal (melted or damaged). Normally, the value will be 0.9 to 1.4.

MAFandDPF Differential Pressure

If the differential pressure in front of and behind the catalyst comes near the value of the “intake air amount multiplied by about 0.4”, the catalyst is probably clogged with PM even if DTC P2002 is not present.

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To update the exhaust fuel addition amount correction value (Exhaust Fuel Addition FB), the engine ●

operation conditions need to meet predetermined conditions. When driving the vehicle to verify the repaired after-treatment system, take a look at the exhaust gas temperature (Exhaust Temperature).Engine problems, such as leakage or clogging in the air intake system or the EGR system, EGR ●

valve problems, and main injector problems, may cause the after-treatment system to operate improperly.For details about the inspection procedures of the catalyst system, refer to relevant TOYOTA repair ●

manuals.

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After-treatment Control (DPNR)71

Description[1[

Purification Mechanism<1< The DPNR catalytic converter employs an NSR catalyst, which stores and reduces NOx, and a DPNR ●

catalyst, which oxidizes CO and HC, stores and reduces NOx, and traps and oxidizes PM.NOx contained in the exhaust gas is catalytically reduced and purified as long as the air-fuel ratio ●

is rich and the exhaust gas temperature is high. During normal combustion where the air-fuel ratio is lean, NOx is stored in the catalyst. The NOx stored in the catalyst will be reduced and purified by regulating the air-fuel ratio to rich with the rich spike control that adds fuel in to the exhaust system.The PM contained in the exhaust gas is trapped by the DPNR catalyst, and in addition to that, will be ●

successively oxidized by the active oxygen that is generated by catalysis while the NOx is stored and reduced.

A/F Lean Rich

Nox

During lean conditions, NOx is stored by changing NOx into NO3 (NO2+O*) temporarily.

The stored NOx is reduced by NO production from the NOx storage layer due to reactions with HC and CO in the exhaust gas under rich conditions.

PM

PM (Particulate Matter) is temporarily captured in the substrate and simultaneously oxidized by oxygen in the exhaust gas and active oxygen from the stored NOx.

Active oxygen, produced by NOx reduction, is used for further PM oxidation.

Substrate SubstrateNox Storage Layer

Pt Pt

Substrate SubstrateNox Stored Layer

PM

PM

Pt Pt

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Catalyst Regeneration<2< If the DPNR catalyst temperature remains low for an extended period so that PM cannot be oxidized, ●

or if the vehicle has been driven for a certain period and the ECM determines that the amount of PM deposited on the DPNR catalyst is higher than a certain amount, the DPNR catalyst regeneration control (PM combustion) is conducted by the ECM, burning the PM deposits.Fuel and engine oils contain sulfur, and when the sulfur content in them has been deposited on the ●

catalyst, the NOx purification becomes less efficient. When the ECM determines that the amount of sulfur deposited exceeds a certain amount, it conducts the catalyst regeneration control (sulfur emission).

Catalyst Regeneration (PM combustion) ■Post Injection Exhaust Port Injection

Substrate SubstrateNox Strage

Layer

PMPM

PM

Pt Pt

DPNR Temp. UP

Catalyst Regeneration (S discharge) ■Lean Rich

Substrate SubstrateDPNR Temp. Up

SulfurSulfur

Pt Pt

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Catalyst Regeneration Flow ■Flow Continuous Regeneration Forcible Regeneration

1: catalyst temperature rise

The temperatures of the NSR and DPNR catalysts rise in accordance with the increase in the exhaust temperature while driving.

The temperatures of the NSR and DPNR catalysts are forcibly increased by the combustion control.

2: PM treatment

PM is oxidized by the oxidat ion reaction that takes place when the catalyst temperature rises.

In addit ion to the PM oxidat ion described to the left, by reacting the high-temperature catalyst with the fuel added by the exhaust fuel addition injector, the temperature of the catalyst is raised further, burning PM.

3: Sulfur treatment -

While the converter bed temperature is stimulated to rise further through the combustion control and exhaust fuel addition, the deposited sulfur is discharged by adjusting the air-fuel ratio to rich.





Mass Air Flow Meter

Exhaust Gas Temp. Sensor

EDU

Injector


ECM






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Accelerator Pedal Position Sensor Used to calculate the amount of fuel added and fuel addition timing for the catalyst regeneration control and rich spike control.

Crankshaft Position Sensor Used to calculate the amount of fuel added and fuel addition timing for the catalyst regeneration control and rich spike control.

Turbo Pressure Sensor Used to correct the amount of fuel added and fuel addition timing for the catalyst regeneration control and rich spike control.

Intake Air Temp. Sensor Used to correct the amount of fuel added and fuel addition timing for the catalyst regeneration control and rich spike control.

Engine Coolant Temp. Sensor Used to correct the amount of fuel added and fuel addition timing for the catalyst regeneration control and rich spike control.


Monitors the combustion control conditions (low temperature lean combustion and low temperature stoichiometric combustion), and feeds the information to each control. Used to detect abnormalities in the exhaust fuel addition injector.

Mass Air Flow Meter Used to calculate the amount of PM deposited on the DPNR catalyst.Differential Pressure Sensor Used to calculate the amount of PM deposited on the DPNR catalyst.

Exhaust Gas Temp. Sensor Used to correct the amount of fuel added for the catalyst regeneration control.

Exhaust Fuel Addition Injector Adds fuel to the exhaust system.

Vehicle Speed Signal Used as a reference signal for starting the catalyst regeneration control.

EDU Drives the injectors when receiving injection request signals from the ECM.

ECM

Controls the catalyst regeneration control and rich spike control according to the sensor signals.Transmits injection request signals to the EDU and the exhaust fuel addition injector.

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Control[3[

Outline<1< Not only for HC and CO purification, in order to make it possible that NOx and PM are reduced ●

simultaneously, the after-treatment system conducts the following controls; PM combustion control [catalyst regeneration control (PM combustion)] that burns PM when the catalyst is determined to be clogged with PM, NOx reduction control, and sulfur poisoning recovery control [catalyst regeneration control (S discharge)] that prevents the NOx purification performance from becoming less effective.Similar to the DPF catalyst, when the amount of PM deposits becomes higher than a certain amount, ●

the catalyst regeneration control (PM combustion) is conducted.In order to periodically discharge the sulfur that was contained in the fuel and oils and has been stored ●

and deposited on the catalyst, the after-treatment system conducts the catalyst regeneration control (S discharge) after completion of the catalyst regeneration control (PM combustion) in succession when the ECM-estimated amount of the sulfur deposited on the catalyst exceeds a predetermined value.In addition to the exhaust fuel addition via the exhaust fuel addition injector provided on the ●

cylinder head, the catalyst regeneration control is conducted through use of the combustion control (temperature rise multiple injection, low temperature stoichiometric combustion, and low temperature lean combustion) that raises the temperature of the exhaust gas emitted from the engine.Furthermore, the NOx stored in the DPNR catalyst is reduced and purified through the following two ●

controls; rich spike control (that makes the air-fuel ratio richer than the stoichiometric air-fuel ratio by adding fuel into the exhaust system), and combustion control (low temperature lean combustion).

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Normal

Cold start

60 ˚C

Time

Control mode

1 2 3 4

8

9 10

5 6 7

Converter bed

temperature

Engine coolant temperatureAmount of PM depositsAmount of S poisoning

Exhaust fuel addition

Vehicle speed

800

Lean

Stoichiometoric

Rich

600

2100

0

0

NOx reduction PM regeneration S poisoning recovery

1 Low temp. combustion starts



4 S poisoning recovery ends

5 Engine coolant temperature

6 Amount of PM deposits

7 Amount of S poisoning

8 Low temperature lean combustion

9 Temp. rise multi-injection

10 Low temperature stoichiometric combustion

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Catalyst regeneration control (PM combustion)<2< When either of the values, the ECM-calculated PM amount that has been deposited on the DPNR ●

catalyst, or the pressure difference between the before and after the catalyst output by the differential pressure sensor fitted on the DPNR catalytic converter, reaches a predetermined value, the catalyst regeneration control (PM combustion) is conducted. The determination from the differential pressure value is obtained through the various information, such as the vehicle driving conditions, intake air amount and differential pressure sensor correction, so that errors will be minimized as much as possible.During catalyst regeneration, when the amount of residual PM estimated from the engine operating ●

conditions and the sensor signals, which are sent by the two exhaust gas temperature sensors fitted on the catalytic converter, is 0g, or when the pressure difference between the before and after the catalytic converter becomes less than a certain value, the catalyst regeneration control ends.Using the temperature rise multiple injection control, the DPNR catalyst regeneration control raises ●

the converter bed temperature to a temperature where the fuel can be added into the exhaust system, and then starts the exhaust fuel addition control, burning PM. (The low temperature lean combustion control is also used partially)

PM regeneration control flow

DPNR catalytic converter bed temp.Amount of PM deposits

Normal combustion

Temp. rise multi-injection

Temp. rise multi-injection and Exhaust fuel addition

Normal combustion

1

2 3

4


2 Rises up to a temperature where exhaust fuel addition becomes possible

3 Maintained high through feedback control with exhaust gas temp. sensor


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1

2 3

55.0

25.0

10.5

0700 2700 3000

Fuel

inje

ctio

n vo

lum

e (m

m3 /s

t)

Engine speed (rpm)

1 Normal combustion


3 Temperature rise multiple injection

REFERENCE The output of the exhaust gas temperature sensor will be 500 to 700 ˚C while the catalyst regeneration ●

control is conducted. The ECM feeds the exhaust gas temperature sensor output into the catalyst regeneration control to prevent the catalyst temperature from rising too high due to the excessive PM deposits.

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Catalyst regeneration control (S discharge)<3< The DPNR converter bed temperature is maintained at more than 600 ˚C using the combustion control ●

(temperature rise multiple injection) and exhaust fuel addition, and the air-fuel ratio is made richer than the stoichiometric air-fuel ratio using the combustion control (low temperature stoichiometric combustion and low temperature lean combustion), this catalyst regeneration control discharges the sulfur deposited on the DPNR catalyst as SO2. Also, the air-fuel ratio is adjusted to rich intermittently, preventing the catalyst from being heated too high.The ECM calculates the amount of sulfur that is deposited on the DPNR catalyst. If the amount of ●

sulfur deposits calculated from the fuel consumption exceeds a predetermined value used to maintain the NOx purification performance at a good level, the catalyst regeneration control (S discharge) is conducted.During catalyst regeneration, when the amount of residual SOx estimated from the engine operating ●

conditions and the sensor signals, which are sent by the air-fuel ratio sensor and two exhaust gas temperature sensors fitted on the catalytic converter, is 0g or becomes less than a certain value, the catalyst regeneration control (S discharge) ends.

Example of S discharge under normal driving conditions ■

More than 600 ˚C

Lean

RichStoichiometric ratio

Air-fuel ratio

Elapsed time

DPNR catalytic converter ded temp.

SO2 discharge amountSO2 is discharged

NSR catalytic converter bed temp.

1

2

3

4

55.0

32.0

10.5

0700 1200 2400 3600

Fuel

inje

ctio

n vo

lum

e (m

m3 /s

t)

Engine speed (rpm)1 Normal combustion


3 Temperature rise multiple injection

4 Low temperature stoichiometric combustion

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NOx reduction<[< The rich spike control is conducted with the fuel addition via the exhaust fuel addition injector. Also, ●

the air-fuel ratio emitted from the engine is adjusted to be richer than the usual through use of the combustion control (low temperature lean combustion), thus, preventing the fuel consumption from becoming less efficient even when the fuel is added into the exhaust system.Through use of the combustion control (low temperature lean combustion), the catalyst is heated ●

to the catalyst active temperature (250-500 ˚C) to conduct the rich spike control, reducing the NOx stored in the DPNR catalyst. During the NOx reduction control, the combustion control (low temperature lean combustion) conditions are monitored through the air-fuel ratio sensor, and that information is used as feedback in the NOx reduction control.

Air-fuel RatioDPNR Catalytic Converter Bed Temp.Exhaust Fuel Addition

Rich Spike

Lean

Rich

500 ˚C

250 ˚C

ON

OFF

Nox Reduction Start

Stoichiometric Ratio

1

2

55.0

10.5

0700 1600 2400 3200

Fuel

inje

ctio

n vo

lum

e (m

m3 /s

t)

Engine speed (rpm)1 Normal combustion


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Exhaust fuel addition<5< In order to secure a high converter bed temperature for the catalyst regeneration control (PM ●

combustion), maintain the converter bed temperature at high and adjust the air-fuel ratio to rich for the catalyst regeneration control (S discharge), and conduct the rich spike control for NOx reduction, fuel is added into the exhaust system.The fuel is added by the exhaust fuel addition injector, which is fitted on the exhaust port of the ●

cylinder head, according to the injection signal from the ECM.The fuel addition amount and timing used in the catalyst regeneration control are calculated in ●

accordance with the engine operating conditions such as a accelerator pedal position and engine speed, and are determined after the corrections from the engine coolant temperature, intake air temperature and manifold absolute pressure. Also, feedback control is conducted based on the exhaust gas temperature and air-fuel ratio sensor signals during the catalyst regeneration. During the catalyst regeneration, when the exhaust gas temperature is lower than the target, or the air-fuel ratio is less lean than the target, the ECM increases the correction value of the calculated exhaust fuel addition amount, and conversely when the temperature is higher or the air-fuel ratio is richer than the target, the ECM reduces the correction value.

Fuel addition by exhaust fuel addition ■

Supply Pump

Injector Spray


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Combustion control and other controls<6< In addition to the exhaust fuel addition control, there are associated controls that support the catalyst ●

regeneration control for increasing catalyst temperatures.Combustion control ■

Control Description

Temperature rise multiple injection

With the same EGR rate and air-fuel ratio configurations as those of the usual combustion mode, post injection is performed in the exhaust stroke after the main injection. This control is conducted in order to raise the converter bed temperature up to a temperature where the converter bed temperature can be increased by the exhaust fuel addition during the catalyst regeneration control.

Low temperature lean combustion

One of the injection modes used in low temperature combustion. By introducing a large amount of EGR, raise the EGR rate to a higher rate than the one where the smoke emission amount reaches the peak to burn fuel. Primarily, this is used in order to raise the temperature in the catalyst in the area where the engine speed and load are low, and reduce NOx emission. With such a high EGR rate the pilot injection is less effective, and the smoke emission amount may increase. Thus, the pilot injection will not be conducted. The target air-fuel ratio in the low temperature lean combustion is set in a range of 19-21.

Low temperature stoichiometric combustion

One of the injection modes used in the low temperature combustion similar to the low temperature lean combustion. This is used in order to secure the conditions necessary to discharge SOx during the catalyst regeneration control (S discharge). The target air-fuel ratio in the low temperature stoichiometric combustion is set in a range of 17-21. The pilot injection will not be conducted.

Glow control On some vehicles, the exhaust temperature is raised by energizing the glow plugs when the catalyst regeneration control begins.

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There are variations depending on the driving conditions, the catalyst regeneration control (PM ●

combustion) is conducted per several hundred kilometers, and a 5-10km distance drive is necessary when the regeneration control is completed. Under the normal driving conditions, the catalyst regeneration control is automatically conducted when PM has been deposited on the catalyst, so deposits and regeneration occur alternately. However, when the vehicle is successively driven for a short distance on one trip, the catalyst regeneration control may not be fully conducted.The catalyst regeneration control (PM combustion) begins when the converter bed temperature is in ●

the normal active range (more than 200 ˚C) and it is determined that the catalyst is clogged after the engine has warmed up. If the vehicle is driven and the engine is turned off before the engine has fully warmed up, or the vehicle is successively driven for a short distance in which the catalyst regeneration control is unable to be completed, PM will continue to be deposited on the catalyst.If the catalyst regeneration control (PM combustion) is conducted when a large amount of PM has ●

been deposited, the heat developed by the PM combustion will exceed the catalyst heat-resistance range, and may cause the catalyst to melt. Thus, in order to prevent the catalyst from being damaged, the catalyst regeneration control will not be conducted either when the calculated value of deposited PM amount, or the signal output from the differential pressure sensor, indicates that the amount of PM deposits exceeds a predetermined level. However, if the catalyst regeneration control is conducted when the PM deposit amount is around a predetermined level, the catalyst may be seriously damaged due to heat deterioration.

Forcible PM regeneration control flow ■

Converter bed temperature (˚C)

Forcible regeneration control

Engine operating conditions Normal

Several hundred km

Forcible PM regeneration

5 to 10 km

Amount of PM deposits (g)

Vehicle speed

Travel distance

0

0

TIP

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Corrections<7< In order to raise the converter bed temperature according to the engine operation conditions, such ●

as idling and driving, the amount of fuel added is determined from the outputs of the various sensors, and furthermore, a target converter bed temperature (exhaust gas temperature) is calculated after correction.

Item DescriptionEngine coolant temperature ●correctionIntake air temperature (behind ●the turbocharger) correctionManifold absolute pressure ●correction

Used to calculate the amount and timing of exhaust fuel addition.

Exhaust fuel addition amount ●correction value (Exhaust Fuel Addition FB)

Used to calculate the amount of exhaust fuel addition. During the catalyst regeneration, when the converter bed temperature (exhaust temperature) does not reach the target temperature, the correction value is increased, increasing the injection amount. When it is higher than the target temperature, the correction value is reduced, reducing the injection amount.

Differential pressure sensor ●correction value

Used to estimate the amount of PM deposited on the catalyst. The sensor output when the ignition switch is in the ON position (the engine has not been started) will be the standard for no pressure difference. When the sensor is normal, the Data List item, Diff. Press. Sensor Corr., should be within the range of -1.5 to 1.5 kPa.

Air-fuel ratio sensor output ●signal

Used to detect abnormalities in the exhaust fuel addition injector. When the fuel is injected, the fuel injection conditions are monitored by referring to changes in the signal waveform of the air-fuel ratio sensor. The air-fuel ratio needs to be richer than the stoichiometric ratio by adding fuel into the exhaust system during the catalyst regeneration control (S discharge), and the sensor output is necessary to perform the feedback control. The feedback control is used to stabilize the low temperature combustion.

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System Confirmation ■Through use of an Intelligent Tester, whether or not the after-treatment system is operating properly ●

can be checked by monitoring the following list items while the Active Test item, [Activate the DPF Rejuvenate (PM)], is performed; Exhaust gas temperature sensor output, AF Lambda B1S1, and Exhaust Fuel Addition FB.During the catalyst regeneration, the exhaust gas temperature value displayed in the Data List, ●

Exhaust Temperature, represents the conditions of the exhaust fuel addition and PM combustion, and AF Lambda B1S1 shows the actual air-fuel ratio based on the stoichiometric air-fuel ratio 14.5 to 1. Also, by looking at the exhaust fuel addition amount correction value (Exhaust Fuel Addition FB), to what degree the exhaust fuel addition amount, which is added by the exhaust fuel addition injector, has been corrected can be checked. The degree of how much PM has been deposited on the catalyst can be roughly estimated through the intake air amount (MAF) and catalyst differential pressure (DPF Differential Pressure).Checking the values will help when the after-treatment system is inspected. ●

Data List Item Diagnostic Note

Exhaust Temperature B1S1Exhaust Temperature B1S2

Used to estimate the converter bed temperature (state of the ●temperature that is raised by adding the fuel) or determine the start timing of the fuel addition through the sensor located before the catalytic converter. The converter bed temperature (PM combustion temperature) is determined through the sensor located after the catalytic converter. Usually, the sensor output will be 500 to 700 ˚C (reference values) while the catalyst regeneration control is conducted.When the value of Exhaust Temperature B1S1 (before the catalytic ●converter) is abnormally high (more than 800 ˚C), it indicates that too much fuel has been added. It may be that the exhaust fuel addition injector has problems, or the ECM has requested more fuel injection than usual due to engine problems.When the value of Exhaust Temperature B1S1 (before the catalytic ●converter) is in the normal range and the value of B1S2 (after the catalytic converter) is abnormally high (more than 800 ˚C), it indicates that the heat generated inside the catalyst is high while the catalyst regeneration is performed. It may be that a large amount of PM has been deposited on the DPNR.Two or more problems described above may occur simultaneously. ●When the temperature before the catalytic converter is high, the sensor located after the catalytic converter is subject to send a high output.

AF Lambda B1S1

When the value is below 0.85, it is suspected that the air-fuel ratio sensor is malfunctioning, or the actual air-fuel ratio is abnormally rich. Furthermore, the exhaust fuel addition injector may have stuck open, or the engine itself has mechanical problems such as the EGR valve stuck open. Normally, the value will be 1.2 to 1.7 (reference values) while the catalyst regeneration control is being conducted.

Exhaust Fuel Addition FB

When the value is abnormally high or remains at its maximum value of 1.99, it is suspected that the converter bed temperature (exhaust gas temperature) during the catalyst regeneration has not reached the target temperature. Possible causes are; the actual exhaust fuel addition amount is low, or the catalyst itself is abnormal (melted or damaged). Normally, the value will be 0.9 to 1.4.

MAF and DPF Dif ferential Pressure

If the differential pressure in front of and behind the catalyst comes near the value of the "intake air amount multiplied by about 0.4", the catalyst is probably clogged with PM even if DTC P2002 is not present.

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To update the exhaust fuel addition amount correction value (Exhaust Fuel Addition FB), the engine ●

operation conditions need to meet predetermined conditions. When driving the vehicle to verify the repaired after-treatment system, take a look at the exhaust gas temperature (Exhaust Temperature).Engine problems, such as leakage or clogging in the air intake system or the EGR system, EGR ●

valve problems, and main injector problems, may cause the after-treatment system to operate improperly.For details about the inspection procedures of the catalyst system, refer to relevant TOYOTA repair ●

manuals.

POINT

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Swirl Control81

Description[1[ In the swirl control, the vacuum taken into the swirl control valve actuator is regulated via the VSV ●

according to the engine operating conditions, this causes the swirl control valve, which is provided on the intake manifold, to open or close, controlling swirls generated inside the combustion chamber.There are two types of swirl controls; one that controls the swirl control valve in two stages, fully open ●

and fully closed, via one VSV, and the other that controls the valve in three stages, fully open, half open and fully closed, via two VSVs. The energization to the VSVs is activated or deactivated by the ECM through switching the built-in transistor on or off.The valve is closed when the engine speed is low to boost swirls inside the cylinder, stabilizing ●

combustion. When the engine is cold, the valve is opened in order to prevent white smoke from being generated.

1 VSV Type ■

Intake Port

Swirl Control ValveCombustion Chamber

Actuator

VSV

ECM

Vacuum Pump

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2 VSV Type ■

Intake Port

Swirl Control ValveCombustion Chamber

Actuator

VSV

VSV

ECM

Vacuum Pump

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VSV


ECM

Component (Signal) Function and PurposeCrankshaft Position Sensor Used to calculate swirl control valve opening degree. *Turbo Pressure Sensor Used to calculate swirl control valve opening degree. *

VSV Opens and closes the vacuum introduction passage to the swirl control valve actuator.

ECMCalculates the swirl control valve opening degree corresponding to the engine operating conditions.Transmits drive signals to the VSV.

Final injection volume Calculated by the injection volume control, and is used as load corrections that are necessary to calculate the swirl control valve opening degree. *

* The one VSV type has two opening degrees, fully open and fully closed. The two VSV type has three opening degrees, fully open, half open and fully closed.

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Control[3[

Swirl control valve control (Two-stage control)<1< Whether a VSV is energized or not (opening or closing the swirl control valve) is determined from the ●

engine speed (NE) and manifold absolute pressure (MAP), and in addition, the load correction value obtained from the final injection volume is applied.The final injection volume, which indicates the value for the engine load condition (engine torque), is ●

determined by the injection volume control. This is calculated from the engine operating conditions, such as the accelerator pedal position, engine speed, mass air flow meter, intake air temperature, and engine coolant temperature.With the area where the engine speed and boost pressure are high, the swirl control valve is opened ●

to make the intake air flow passage wide. Conversely, with the area where the engine speed and boost pressure are low, the valve is closed to narrow the intake air flow passage, making the swirl intense inside the cylinder.

Valve closure area

Valve open area50

3000

Boo

st p

ress

ure

(kPa

)

Engine speed (rpm)

Energization characteristics ■ECM built-in transistor VSV Swirl control valve

OFF Not energized OpenON Energized Closed

On vehicles with the catalyst after-treatment control (DPF catalytic converter), while the catalyst ●

regeneration control is being conducted, the swirl control valve closure area calculated by the ECM is limited (expanding the valve open area), preventing the catalyst purification performance from becoming less efficient.

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Swirl control valve control (Three-stage control)<2< The three-stage control uses two VSVs and holds the swirl control valve at the half open position ●

when transitioning from fully open/closed to fully closed/open, changing the intensity of the swirls inside the cylinder smoothly as well as preventing the combustion from changing rapidly.

Three-stage swirl control valve control characteristics ■VSV1 VSV2 Swirl control valve

Energized Energized Fully ClosedEnergized Not energized Half open

Not energized Not energized Fully Open

Valve fully closed area

Valve half open area

Valve fully open area50

3000

Boo

st p

ress

ure

(kPa

)

Engine speed (rpm)

Corrections<3< In order to generate swirls appropriate to the engine operating conditions, the VSV energization timing ●

is calculated depending on the intake air amount and engine load.

Item Description

Load correction

Used to calculate the VSV energization timing.

This is a correction value that represents the engine control conditions (engine load), and is obtained from the final injection volume calculated by the injection volume control.

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EGR Control91

Description[1[ On diesel engines, since the excess air ratio during combustion is high (1.2 to 4.0), a three-way ●

catalyst that is effective for NOx reduction cannot be used. Therefore, through use of the EGR system, the exhaust gas is partially taken into the intake side in order to adjust the combustion conditions to be less efficient to a degree where the driving performance is not affected, and then the peak combustion temperature is allowed to fall, reducing the amount of NOx. However, when high-temperature EGR gases are taken the the filling efficiency becomes low, so EGR gases are cooled by the EGR cooler to increase the EGR amount and reduce the combustion temperature, attempting further NOx reduction. Also, some vehicles are equipped with a DPNR catalytic converter that is effective for NOx and PM reduction, reducing NOx using catalysts too.

Engine

EGR Valve

EGR Cooler

EGR Cooler Bypass Switching Valve


To Turbocharger

Exhaust Gas

Engine ECU

Stoichimetric air-fuel ratio

Relationship between amounts of generated CO, HC and NOx

Combustion gas temperature and NOx concentration

Am

ount

gen

erat

ed

NO

x co

ncen

tratio

n

Nox

10Rich

LowAir-fuel ratio

Combustion gas temp.Lean

12 14 16 18 20

COHC

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Mass Air Flow Meter


EGR Valve


ECM

Component Function and PurposeCrankshaft Position Sensor Used to calculate the basic EGR valve opening degree.Turbo Pressure Sensor Used to calculate the EGR rate.Mass Air Flow Meter Used to calculate the EGR rate.

EGR Valve Position SensorUsed to detect actual opening degree of the EGR valve, and also used to calculate the deviation from the target valve opening degree.

EGR Valve Controls the intake EGR gas amount.Calculates the basic EGR valve opening degree.Calculates the f inal target EGR valve opening degree af ter correcting the basic EGR valve opening degree.Calculates the deviation between the actual and target valve opening degrees, and then drives the EGR valve.Calculates the target EGR rate, and regulates the EGR valve through feedback control.

Final injection volume Calculated by the injection volume control and is used to calculate the basic EGR valve opening degree.

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Control[3[

Outline<1< The ECM calculates the basic EGR valve opening degree based on the engine speed and the final ●

injection volume which is calculated by the injection volume control. The ECM corrects the calculated basic EGR valve opening degree according to the various sensors to make it appropriate to the engine operating conditions, and drives the EGR valve so that the EGR valve position sensor value comes to the target value. Also, even if the valve opening degree is constant, the EGR flow amount (EGR rate) changes due to the engine operating conditions and time, so the ECM monitors EGR flow amount to perform feedback corrections.


Final target EGR valve opening degree

Calculating the variation between the actual and target valve opening

degrees

Driving EGR valve

Basic EGR valve opening degree Correction coefficient

EGR feedback control

Engine Speed Signals

EGR Control



REFERENCE

EGR deactivation conditions (2AD-FHV) ■Condition Item Situation

1 Engine coolant temperature Outside the range of 15 to 96 ˚C2 Engine speed Outside the range of 675 to 4400 rpm

3 Accelerator pedal depression degree

70% or more, or the load coefficient from the final injection volume is above a certain level.

4 Long idling 20 minutes or more have elapsed.

* If any one of the conditions shown above is met the EGR control is deactivated.* The thresholds vary depending on the engines.

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Basic EGR valve opening degree calculation<2< The ECM calculates the basic EGR valve opening degree based on the engine speed and the final ●

injection volume which is calculated by the injection volume control. The basic EGR valve opening degree map is as shown below, and when the engine load is low, a large amount of EGR is taken, so that NOx can be reduced aggressively.

Basic EGR valve opening degree ■

Engine speed (rpm)

60

30

10

0

0 %

59 %

70 %

74 % 77 %

70~75 %

60~70 %

70 %

59 %0 %

600 1000 1400 1800 2200 2600 3400 3600

Inje

ctio

n vo

lum

e (m

m3 /s

t)

Feedback control<3< Even if the EGR valve opening degrees are the same, the EGR flow amount varies depending on ●

the engine load, diesel throttle valve opening degree, and amount of carbon deposited on the EGR passage. In order to achieve the target EGR flow amount (EGR rate), the ECM calculates the EGR flow amount by comparing the following values; the fresh air volume from the mass air flow meter, intake air amount calculated from engine displacement and engine speed, and manifold absolute pressure signal, and then performs feedback control increasing or reducing the opening degree of the EGR valve.In addition, to obtain the target EGR flow amount (EGR rate) as accurate as it can be, the EGR ●

cooperative control in association with diesel throttle control, in which the intake manifold vacuum and fresh air volume is regulated, is conducted at the same time. (Refer to Diesel Throttle Control - EGR Cooperative Control)

EGR rate difference at a same EGR valve opening degree ■Case Engine Speed Target EGR

EGR valve opening degree

MAF MAP EGR rate

Case 1 1050 49.0 54.6 5.76 94 72%Case 2 1800 49.0 54.6 12.71 94 64%

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Combustion control<[< Low temperature combustion control is used to reduce smoke and NOx, and determines and sets ●

air-fuel ratios depending on the EGR rate. On the vehicles with DPF/DPNR catalytic converters, the low temperature combustion control (temperature rise multiple injection, low temperature lean combustion, and low temperature stoichiometric combustion) is conducted so that converter bed temperature is raised during the catalyst after-treatment control.While the exhaust gas temperature is raised by increasing the EGR flow amount (EGR rate) to a large ●

extent, the air-fuel ratio is adjusted to rich, supporting the controls such as catalytic converter PM deposit combustion, sulfur poisoning recovery, and NOx reduction.

Air Fuel RatioLean

EGR Volume

Stoichiometric

Low Temp.Combusion Area

NormalCombustion Area

: Smoke: NOx: CO/HC

Rich

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EGR flow amount monitoring by ECM<5< Unlike gasoline engines, diesel engines do not regulate the intake air amount via the throttle valve, ●

thus, the intake pipe pressure is basically constant when the engine not turbocharged. When the EGR valve is opened, the exhaust gas coming through the EGR valve will be taken into the engine, so the amount of fresh air taken from the air cleaner will decrease, as a result, the intake air amount detected by the mass air flow meter will be less. The ECM monitors the EGR flow amount by reading this change in the mass air flow meter signal.

Intake Restrictor Valve Intake Restrictor Valve

EGR Valve

EGR Valve

EGR Cooler EGR Cooler

Engine Engine

If the mass air flow meter value does not change even when the EGR valve is opened, the ECM ●

interprets it as the EGR valve being clogged and sets P0400.

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Data under EGR control (ALE21 with 2AD-FHV)<6< Idling ■

EGR

No EGR

By reducing the diesel throttle valve opening degree, manifold pressure falls, allowing the EGR gas to enter

By reducing the diesel throttle valve opening degree, manifold pressure falls, allowing the EGR gas to enter

Diesel throttle valve opening degree increases, hence, MAF value rises

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Acceleration and deceleration ■

EGR volume is increased up to maximum level during deceleration

When engine load is low, taking EGR gas into intake sideWhen engine load is

high, EGR control is deactivated

Relationship between EGR and exhaust gas temperature (combustion temperature) ■

After EGR cut-off, exhaust gas temperature (combustion temperature) starts rising

EGR gas is cut off

After EGR cut-off, exhaust gas temperature (combustion temperature) starts rising

When the EGR control is deactivated, no exhaust gas is taken into the combustion chamber, and fuel can burn more, hence, the exhaust gas temperature will rise. The movement of the temperature shown in the graph above was monitored under idling conditions, so exhaust gas temperatures will rise higher under actual driving conditions.

POINT

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System Confirmation ■Through use of an Intelligent Tester, whether or not the EGR valve is operating properly can be ●

checked by monitoring the following list item while the Active Test item, [Control the EGR Step Position], is performed; EGR valve position sensor output [EGR Lift Sensor Output]. In addition, learned full close positions of the EGR valve can be checked through the display value at [EGR Close Learn Val.] with the sensor output voltage display. The full close learning status can be checked with the Data List item [EGR Close Lrn. Status].When closing the EGR valve using the Active Test function, see if the EGR valve position sensor ●

output value smoothly changes to the one corresponding to the set valve opening degree. (Whether or not the sensor output value will be within a range of plus or minus 10% of the set value of the valve opening degree.) When normal, the EGR valve position sensor output will be as shown below.

Target EGR Position EGR Valve Condition EGR Lift Sensor Output(Sensor Output Voltage)

0% Fully closed 80.0 +/- 10 %(4.0 +/- 0.5 V)

100% Fully open 26.0 +/- 10 %(1.3 +/- 0.5 V)

Target EGR Position

EGR Lift Sensor Output

Fully Closed

+/- 10%

Fully OpenEGR Valve Opening

(%)

(%)(V)(5)

(0)

100

100

0

0

If the Data List item [EGR Close Lrn. Status] shows [NG], the learning value [EGR Close Learn Val.] ●

will be the default value of 4.0V, or the value updated at the last moment when it was normal. The value is not the latest, thus, it will not be useful.If the result of the inspection described above is that the display value is not normal, carbon may ●

have been deposited on the EGR valve, EGR passage, intake system, and exhaust system. In addition, engine problems, which cause a large amount of black smoke to be emitted, may have occurred.

Depending on the vehicle models, the EGR lift sensor output characteristics may be opposite to the description here.

NOTICE

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EGR Cooler Bypass Valve111

Description[1[ The ECM controls the EGR cooler bypass valve, which is fitted on the outlet port of the EGR cooler, ●

via the VSV in accordance with the engine operating conditions, thus optimizing the temperature of the EGR gas that is recirculated into the intake passage and further improving the exhaust gas purification performance after engine start.When the engine is cold or the engine load is low, if the compression heat in the engine compression ●

stroke is determined to be insufficient due to a low intake air temperature, the ECM opens the bypass valve and recirculates the EGR gas bypassing the EGR cooler into the intake air passage.

Engine

EGR Valve

EGR CoolerEGR Cooler Bypass Switching Valve


To Turbocharger

Exhaust Gas

ECM




VSV


ECM

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Crankshaft Position Sensor Used to determine which valve, either the EGR cooler bypass valve on the bypass passage side or on the cooler side, to open.

Engine Coolant Temperature Sensor Used to determine which valve, either the EGR cooler bypass valve on the bypass passage side or on the cooler side, to open.

VSV Opens and closes the vacuum introduction passage to the EGR bypass valve actuator.

ECM

Determines which valve, either the EGR cooler bypass valve on the bypass passage side or on the cooler side, to open in accordance with the engine operating conditions.Transmits drive signals to the VSV.

Final injection volumeCalculated by the injection volume control, and used to determine which valve, either the EGR cooler bypass valve on the bypass passage side or on the cooler side, to open.

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Control[3[

Outline<1< Energization of the VSV to switch the EGR cooler bypass valve is controlled by the ON/OFF timing ●

which is calculated based on the final injection volume, engine speed and engine coolant temperature. (Map calculation)The final injection volume, which indicates the value for the engine load condition (engine torque), is ●

determined by the injection volume control.The ECM energizes the VSV, either in the EGR operating range during engine warm-up phase (at the ●

low temperature of the engine coolant) or in a range from a non-injection state to a nearly non-loaded state during perfect warm-up phase, and activates the actuator to bypass the EGR gas passing through the EGR cooler.

VSVEGR cooler condition

Bypass side Cooler sideEnergized Open Close

Not energized Close Open

VSV energization map ■High

Load

(Fin

al in

ject

ion

volu

me)

Engine Speed (rpm)

Low

VSV: On range(Bypassed)

VSV: Off range(Not bypassed)

Engine

3000

In vehicles equipped with DPNR, in order to raise the exhaust gas temperature under control of after- ●

treatment such as the temperature rise multiple injection control or the low temperature combustion control, the EGR cooler bypass range (VSV ON range) is widened and the EGR gas introduction rate is increased.

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Diesel Throttle Control111

Description[1[ Under the diesel throttle control, the ECM regulates the diesel throttle valve opening degree in ●

accordance with the engine operating conditions, ensuring the intake EGR amount, preventing the engine from overspeeding and reducing the engine vibrations at engine stop.The diesel throttle control has the following controls: a specified condition control to protect the engine ●

and reduce engine vibration, which is performed when the engine meets a specified condition, and a normal control relating to the combustion control and the EGR control which are mainly for exhaust gas after-treatment.

Engine

EGR Valve

EGR Cooler

EGR Cooler Bypass Switching Valve


To Turbocharger

Exhaust Gas

ECM

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Starter Signal

EGR Valve

Diesel Throttle Control Motor


ECM


Used as a specified condition control performance condition

Used as a specified condition control performance conditionUsed to calculate the basic throttle opening degree under normal control.

Turbo Pressure Sensor Used to calculate the EGR rate.Throttle Position Sensor Used for feedback control of the diesel throttle valve opening degree. EGR Valve Position Sensor Used to calculate the EGR rateStarter Signal Used as a specified condition control performance condition.Diesel Throttle Control Motor Controls the intake air amount. EGR Valve Controls the intake EGR gas amount.

ECM

Calculates the basic diesel throttle valve opening degree.Calculates the target diesel throttle valve opening degree, to which corrections are applied to the basic diesel throttle valve opening degree. Performs feedback control of the diesel throttle valve opening degree, based on the actual diesel throttle valve opening degree from the throttle position sensor. Transmits drive command signals to the diesel throttle control motor. Transmits drive command signals to the EGR valve.

Final injection volume Calculated by the injection volume control and is used to calculate the basic throttle opening degree.

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Control[3[

Specified condition control<1<

General(1) In order to protect the engine from overspeeding and abnormal fuel pressure rise, and to reduce the ●

engine vibration at engine stop, when the engine meets specified conditions, the diesel throttle valve is controlled as follows:

Engine condition Diesel throttle opening degree Diagnostic Note

When the engine stops. Fully Closed

Vibration is reduced when the engine stops.

Learning of fully closed position of the diesel throttle valve is performed.

When running at abnormally high speed. (approx. 5000 rpm or more) Half closed Recovery engine speed:2800 rpm

When the engine speed abnormally rises Half closed

This applies when the accelerator opening degree is 2% or less and the engine speed of 1600rpm or more continues for 1 second.

When the starter is on.(When STA signal is input.) Fully Open Startabiilty is improved

When the fuel pressure is abnormally high. Half closed When high fuel pressure DTC is detected.

During evacuation running before the engine stalls. Half closed A few minutes before fail-safe is activated

when low fuel pressure DTC is detected.

REFERENCE In diesel engines, torque can be generated even in the combustion of engine oil. Therefore, the engine ●

speed is limited by restricting the intake air amount or cutting off the intake air when the engine speed abnormally increases in a case that engine oil enters into the combustion chamber due to an oil leakage.

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Engine is stopped (ALE21 with 2AD-FHV)(2)

ONIGSW

MREL

LUSV

VLU

Ne

ON

OFF

OFF

OpenClose

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IIgnition switch is turned from OFF to ON

Main relay remains ON

Immediately after the engine has started, diesel

throttle valve opening degree control starts

Ignition switch is turned from ON to OFF

Main relay remains ON

Diesel throttle valve full closure control starts(Engine is stopped)

Diesel throttle valve open control starts

(Start performance improvement for next

start)

Main relay turns OFF

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Normal Control<2<

Calculation of Diesel Throttle Valve Opening Degree(1) The ECM calculates the basic throttle valve opening degree based on the engine speed and the ●

final injection volume which is calculated by the injection volume control. In accordance with the engine conditions, the ECM determines the target throttle valve opening degree by the product of the correction coefficient which is calculated based on the values from various sensors and the basic throttle valve opening degree, and drives the diesel throttle valve.In diesel throttles which are driven by the rotary solenoid or the DC motor, the throttle valve position ●

sensor detects the actual diesel throttle valve opening degree and that value is used as feedback in the diesel throttle control. The ECM drives the diesel throttle valve to make the value from the throttle position sensor equal to the target value.


Basic Throttle Valve Opening Degree

Correction Coefficient to calculate the Target

Throttle Opening Degree

Target Throttle Valve Opening Degree


Diesel Throttle Control


Engine Speed Signals(NE)

Throttle Valve

Position Sensor

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Cooperative Control of EGR(2) By performing the cooperative control of the EGR valve control and the diesel throttle control, the ●

optimal EGR rate in the intake air is ensured in accordance with the engine operating conditions. The EGR rate varies in accordance with the diesel throttle valve opening degree even if the engine speed and the lift amount of the EGR valve are constant. By monitoring the diesel throttle valve opening degree by the throttle valve position sensor and performing feedback correction based on that information, an appropriate valve opening degree and a target EGR rate in the intake air are obtained.The intake air into the cylinder contains fresh air from the air cleaner and EGR gas, however, the ●

diesel throttle valve opening degree is a crucial element to determine the EGR rate in the amount of the EGR gas/intake air into the cylinder. This also significantly affects the air-fuel ratio which is used for combustion control.

Effects of Diesel Throttle Valve and EGR Valve Opening Degree ■Item Effects

Diesel throttle vale opening degreeThe more the valve is closed, the more the vacuum increases. When the EGR valve is open, the EGR rate increases and fresh air rate decreases.

EGR valve opening degree The more the EGR valve is opened, the more EGR gas enters the intake pipe and the lower the vacuum is.

Manifold Absolute Pressure

Under the control of the EGR, the MAP pressure decreases due to a pressure loss in the diesel throttle, however, the decrease in the pressure is compensated by the EGR and is made equal to the atmospheric pressure.(Except in the case of applying the boost pressure.)

Intake air into the cylinder ■MAP Sensor

EGR Valve

Diesel Throttle Valve

EGR Compensation

Fresh Air

EGR Gas

When no boost pressure is applied (natural air intake mode):

MAP ≈ Atmospheric Pressure - Pressure Loss in the Diesel Throttle Valve + EGR Compensation

Pressure Loss in the Diesel Throttle Valve

Air Cleaner

Engine

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EGR cooperative control (VDJ200 with 1VD-FTV) ■

Since EGR gas is allowed to enter, EGR valve is open

In order to allow EGR gas to enter, diesel throttle valve is closed

Diesel throttle valve is closed, thus, manifold pressure is low (EGR gas volume is increased due to manifold vacuum)

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Normal (without cooperative control) ■

EGR gas is cut off, hence, EGR valve is fully closed

EGR gas is cut off, thus, diesel throttle valve is fully open

Since diesel throttle valve is fully open, MAF value rises according to increases in engine speed

Diesel throttle valve is fully open and no turbocharger boost pressure is applied, hence, it is almost atmospheric pressure

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Operation check of the diesel throttle valve ■Check the valve opening degree and operation using an intelligent tester. ●

Data List/Actual Throttle Position (Reference values on AD engines)

Engine Condition Specified Condition Diagnostic Note

Ignition switch ON -5 to 5 %

The diesel throttle valve is fully opened when the engine stops. However, when the ignition switch is turned from on to off, the diesel throttle valve is closed once to reduce vibration when the engine stops. At this time, the ECM learns the diesel throttle valve fully closed position.

Idling 81 to 95 %

The values are reference values, after the engine is warmed up and while running at an altitude near sea level. The diesel throttle valve opening degree varies in accordance with the atmospheric pressure.

Accelerator pedal fully depressed -5 to 5 %

When running the engine at full load, EGR introduction is cancelled, instead of introducing a large amount of fresh air from the air cleaner.

Acceleration and deceleration

Value changes s m o o t h l y i n transition

Check that the diesel throttle valve operates smoothly over the entire operating degree. When the valve does not operate smoothly, check along with the following item: Throttle Motor DUTY.

Data List/Throttle Motor Duty (Reference values for AD engines)

Engine Condition Specified Condition Diagnostic Note

Idling, acceleration, and deceleration

50 +/-40 %

When the values of 10% or less or 90% or more remain displayed, it is believed that there may be a malfunction in the diesel throttle body. The ECM outputs drive commands at minimum duty (valve open) or at maximum duty (valve closed), to allow the valve opening degree to follow the target opening degree. When this lasts for approximately 30 seconds, DTCs are output.

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Check of Air Intake Systems (Corrected MAF Value) ■Carbon deposits or icing in the diesel throttle body may cause the diesel throttle valve to malfunction. ●

When carbon deposits are visible in the diesel throttle body, the deposits may be formed in the EGR systems, catalyst or other intake/exhaust air systems. Therefore, troubleshooting the causes of the deposits must be performed and the areas of depositions must be cleaned. Especially, the carbon deposition is relatively easily formed when the engine emits black smoke.In the intake air system including the diesel throttle body, black smoke is generated when the intake ●

air volume deviates from the injection volume due to air leakage or clogging. In this case, calculate a value at near maximum engine speed at no load (at the cancellation of the EGR) using the following formula, and narrow down the areas of air leakage by comparing the calculated data with the reference value.

Corrected MAF Value (Reference values for AD engines)Calculation formula Reference value

MAF (g/sec) x 4500 / Engine Speed (rpm) x 145 / MAP (kPa) 1AD: 95 +/- 5 g/sec2AD: 105 +/- 5 g/sec

Calculation Ex.: Reference data (for 2AD engines): ●

Engine speed: 4350 rpm, MAP: 142.1 kPa, MAF: 96.7 g/sec ●

96.7 x 4500 / 4350 x 145 / 142.1 = 102.08 ●

The calculated value of 102.08 is within standard range of 105 +/- 5 g/sec ●

When the corrected MAF value, calculated by the above formula, is above the reference value, air ●

leakage may occur between the turbocharger and the intake manifold. When the value is below the reference value, air leakage may occur between the air cleaner (behind the intake air flow meter) and the turbocharger.

Air leakage between turbocharger and intake manifold

MAF MeterBlack Smoke

intake

Exhaust

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Turbocharger Control121

Description[1[ The variable nozzle vane type turbocharger has made great improvements in low-speed torque, ●

maximum output, fuel consumption, and emission reduction. These improvements have been accomplished through variable control of the nozzle vane angle, and maintaining an optimal velocity of the exhaust gas inflow to the turbine at all times in response to the engine conditions.The ECM controls the nozzle vane angle, in order to obtain the calculated target boost pressure ●

appropriate to the engine operating condition.As a basic control, the feedback control is conducted to gain a boost pressure determined from the ●

engine operating conditions (lower the boost pressure: open the variable nozzle, increase the boost pressure: close the variable nozzle), but an open control will be conducted in the EGR operating range to gain an angle determined from the engine operating conditions.

VRV

Actuator

Vacuum Pump


Engine ECU

Basic Control of Variable Nozzle Vane Turbocharger ■Engine Condition Purpose

Low and Medium Engine Speed To improve boost pressure increase characteristicsTo reduce black smoke emission

High Engine Speed To improve fuel economy and outputTo prevent turbine overspeed

During EGR Operation To stabilize EGR amount

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VRV


Atmospheric Pressure Sensor

ECMTurbo Pressure Sensor

Component Function and Purpose

Crankshaft Position Sensor Used to calculate the basic nozzle vane opening degree and the basic target boost pressure.

Turbo Pressure Sensor Used to calculate the boost pressure feedback amount.

Intake Air Temperature Sensor Used to determine whether the engine is in a cold condition or not. Used as a correction value for the basic nozzle vane opening degree and the basic target boost pressure.

Atmospheric Pressure Sensor Used as a correction value for the basic nozzle vane opening degree and the basic target boost pressure.


Used to determine whether the engine is in a cold condition or not. Used as a correction value for the basic nozzle vane opening degree and the basic target boost pressure.

VRV Opens and closes the vacuum introduction passage to the actuator which controls the nozzle vane angle.

ECM

Calculates the basic nozzle vane opening degree and the basic target boost pressure.Calculates the boost pressure feedback amount based on the deviation between the target boost pressure to which corrections are applied to the basic target boost pressure, and the actual boost pressure Calculates the final nozzle vane opening degree by applying corrections and boost pressure feedback to the basic nozzle vane opening degree. Transmits drive command signals to the VRV.


Calculated by the injection volume control, and is used to calculate the basic nozzle vane opening degree and the basic target boost pressure.

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Control[3[

Outline<1< The turbocharger control controls the nozzle vane opening degree to obtain the target boost pressure. ●

The turbocharger control has the following controls: One is the nozzle vane opening degree control to obtain appropriate exhaust gas pressure and flow rate for the turbocharger in accordance with the engine opening conditions, and the other is the boost pressure control which corrects difference to the target boost pressure, based on the manifold absolute pressure sensor output signals (MAP).The ECM determines the nozzle vane opening degree from various sensor signals and values ●

calculated by the other controls, and drives the nozzle vane. Then, in order to make the boost pressure (manifold absolute pressure sensor output signal) to be the target boost pressure, a boost pressure control value is applied to the nozzle vane opening degree control and the final nozzle vane opening degree is determined.

Nozzle vane opening degree control

Boost pressure control

ECM

Nozzle vane actuator (Turbocharger)

Manifold Absolute Pressure Sensor

(Intake Manifold)

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Nozzle Vane Opening Degree Control<2< The basic nozzle vane opening degree is calculated based on the engine speed and the final injection ●

volume calculated by the injection volume control. (Map calculation)By applying the atmospheric pressure correction, engine cold condition determination correction ●

which is determined based on the intake air temperature and the engine coolant temperature, the EGR control status, and the status under the after-treatment control using things such as DPF or DPNR catalytic converter, and furthermore, applying the boost pressure feedback (to be described) to the basic nozzle vane opening degree, the final nozzle vane opening degree is obtained. The ECM drives the turbocharger nozzle vane actuator based on the final nozzle vane opening degree.


Final nozzle vane opening degree

Nozzle vane actuator(Turbo motor driver)

Basic nozzle vane opening degree

Atmospheric correctionEngine cold condition determinationEGR control statusAfter-treatment control status

Boost pressure feedback

Turbo Pressure Control


Boost pressure control

Engine speed signals (NE)

REFERENCE In a communication type turbocharger system, the final nozzle vane opening degree signals are ●

transmitted to the turbo motor driver, driving the nozzle vane actuator (DC motor). In addition, the turbo motor driver determines the actual nozzle vane position using the nozzle vane position sensor, and then strictly regulates the nozzle vane opening degree to be the command value (final nozzle vane opening degree position) from the ECMWhen the vacuum actuator, which is controlled by DUTY control of the E-VRV, is used for the nozzle ●

vane actuator, the ECM directly drives the E-VRV and controls the nozzle vane position.When the EGR control is performed, the exhaust gas after-treatment control using things such as DPF ●

or DPNR is changed to an open loop control, in which the feedback is not carried out, to stabilize the combustion control.

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Boost Pressure Control<3< The basic target boost pressure is calculated based on the engine speed and the final injection ●

volume calculated by the injection volume control.By applying the atmospheric pressure correction, the engine cold condition determination correction, ●

the EGR conrol status and status under the after-treatment control using things such as DPF or DPNR catalytic converter, to the basic target boost pressure, and furthermore, applying the deviation to the actual boost pressure which is calculated from the manifold absolute pressure sensor output signal to the basic target boost pressure, the obtained information is fed back to the nozzle vane control, and the ECM determins the final nozzle vane opening degree.


Calculation of deviation of actual and target boost pressuresCalculation of boost pressure feedback amount

Nozzle vane opening degree control

Final nozzle vane opening degree

Basic target boost pressure

Atmospheric pressure CorrectionEngine cold condition determination correctionEGR control statusAfter-treatment control status

Turbo Pressure Control


Manifold Absolute Pressure Sensor

Engine speed signals (NE)

REFERENCE When running the engine in a high altitude area such as mountains, the boost pressure becomes ●

hard to raise due to low atmospheric pressure. Therefore, if the atmospheric pressure decreases in a situation where the target boost pressure value is set to be constant, the turbocharger speed must be increased by controlling the nozzle vane to closer than normal to make the target boost pressure equal to the actual target boost pressure. In short, if the atmospheric pressure decreases while the turbocharger operates at a high rotation speed, this may cause the turbocharger to rotate excessively. To prevent the turbocharger from overrotating in a low atmospheric pressure, the ECM controls the nozzle vane position by monitoring the atmospheric pressure correction, mass air flow (MAF) at a low atmospheric pressure and the engine speed.

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Various Corrections<[< In order to obtain an optimal nozzle vane opening degree in accordance with the engine operating ●

conditions, corrections are applied to the basic nozzle vane opening degree and the basic target boost pressure based on values from the various sensors.

Item Content

Atmospheric pressure correction

Engine cold condition determination

Used to calculate the final nozzle bane opening degree.

Used to limit the boost pressure in cold engine condition and limit the turbo charger speed at high altitude.

EGR control status

After-treatment control status

Used to calculate the basic nozzle vane opening degree and the basic target boost pressure.

REFERENCE In the ECM, the drive amount of the turbocharger actuator is integrated, and if the integrated value ●

exceeds a predetermined value and the engine is in a stable idle state, the nozzle vane is fully opened and closed once for deposition removal to prevent the nozzle vane from sticking due to foreign objects such as soot sticking to the turbocharger nozzle vane link mechanism.

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7 Others9

Exhaust Gas Control System11

Description[1[ The exhaust gas control system closes the valve located downstream of the oxidation catalytic ●

converter when the engine conditions meet the predetermined conditions while the engine is cold, to ensure the engine warm-up performance and heater performance.This system consists of an idle-up switch, an exhaust gas control valve, a vacuum actuator that ●

is linked with the valve, a vacuum switching valve (VSV), and the ECM that controls the vacuum switching valve.The ECM operates the electronic vacuum switching valve in accordance with the engine operating ●

conditions and also operates the vacuum actuator that is linked with the exhaust gas control valve. When the exhaust gas control valve is closed, the engine back pressure becomes larger, and so does the pumping loss. The loss makes the engine load larger, causing the exhaust temperature to rise. As a result, time it takes to warm up the engine is reduced.


Exhaust Gas Control Valve

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System block diagram ■

Air Cleaner

ECM

Vacuum Pump

VSV



Water Temp. Sensor


Air Flow Meter

Crankshaft Position SensorAccelerator Pedal Position SensorAtmospheric Temp. SensorIdle-up Switch

REFERENCE The exhaust gas control valve used on the 1KD-FTV engine for Japan (as of October 2008) helps the ●

catalyst temperature to rise, in order to reduce time for completing PM recovery.As with the exhaust gas control system described in this chapter, it takes the vacuum into the exhaust ●

gas control valve and opens and closes the valve via the VSV controlled by the ECM.

Air Cleaner

ECM

Vacuum Pump

VSV


Air-fuel Ratio Sensor

Oil Level Sensor

Other Sensors

Exhaust Gas Temperature Sensor (up stream)

Exhaust Gas Temperature Sensor (down stream)Exhaust Gas Pressure

Sensor

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Operating Condition[2[ This system operates when the idle-up switch is on while all of the following conditions are satisfied: ●

EGR system is operating ●

Engine coolant temperature is below 70 ˚C ●

Air inlet port intake air temperature is below 5 ˚C ●

At least 10 seconds have elapsed after engine start ●

Engine speed and fuel injection volume are within the range specified in the graph below ●

Engine Speed

Activation Range

Injection Volume

Operation[3[ When the ECM satisfies all the aforementioned operation conditions, it energizes and operates the ●

VSV. This switches the vacuum route, operates the connected vacuum actuator and then closes the linked exhaust gas control valve.

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Circuit[[[

Exhaust Gas Control System Circuit<1<

Microprocessor

ECM

VSV for Exhaust Gas Control

Warm Up Switch

12 V

12 V

HSW

MREL

E1

HEFX

MAIN

Battery

Drive Circuit

Interface


* Fail detection circuit is applied depending on the type of vehicle.

Drive Voltage<2<


HEXFVSV Control Output

Normal(Valve close condition: HSW ON, Cold engine, Idling) Below 1.5 V

Normal(Valve open condition: Engine warmed up, 3000 rpm) 12V

HEXF circuit open Remains 0 VHEXF circuit ground short Remains 0 V

VSV itself shorted Remains 12V



Exhaust Gas CTL VSV Activate VSV (for exhaust gas control valve):ON/OFF

The applicable items vary depending on the vehicle. For details about the Active Test, refer to the * relevant repair manuals.An Intelligent Tester cannot show the exhaust gas control valve drive signal (VSV drive signal).*

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In-Tank Fuel Pump System21

Description[1[ On the vehicles with a separate fuel sub tank (Land Cruiser Prado for Australia) and with a saddle- ●

shaped fuel tank (LEXUS IS220d), in order to use the fuel stored in the divided reservoirs equally, an electric fuel pump provided inside the fuel tank is employed to equalize the amounts of the remaining fuel. (Fuel transfer mode)Also, vehicles equipped with a saddle-shaped fuel tank (LEXUS IS220d) can operate priming mode, ●

which is used when air enters between the fuel tank and the supply pump when running out of fuel, by an electric fuel pump. (Priming mode)The in-tank fuel pump system consists of an electric fuel pump, a jet pump, a fuel pump relay, and the ●

ECM that drives the relay. Furthermore, on the vehicle models that have priming mode, a fuel route switching valve and a PCV relay are provided. The PCV relay supplies the power to the fuel route switching valve.

Fuel Pump

Chamber A Chamber B

Fuel Tank Solenoid

Jet Pump

Supply Pump

Engine

Fuel Sedimenter Fuel Filter

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Operating Condition[2[ When the engine starts or the amount of fuel consumption reaches the threshold value, the ECM ●

drives the electric fuel pump for approximately one minute and restores the amount of fuel in the main fuel tank (main chamber).When the fuel remaining in the main fuel tank (main chamber) decreases below a certain amount ●

(approximately 17.1L), the ECM drives the electric pump until the remaining fuel amount exceeds the predetermined amount (more than approximately 20.3L). However, this operation will not be conducted when the fuel remaining in the sub fuel tank (sub chamber) is less than a certain amount (approximately 4.5L).

Engine Start

from a sharp turn etc.

Approx 1 min.

Fuel Consumption Count(Liter)

Fuel Pump

Fuel Level (Main)

20.3L

MS

17.1L

0.5

0

ON

OFF

REFERENCE This section describes about the operation conditions of the Lexus IS220d. The operating conditions ●

vary depending on the vehicles.

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Operation [3[

Fuel transfer mode<1<

General(1) According to the remaining fuel amount calculated from the fuel consumption, the ECM turns on the ●

relay to drive the fuel pump when the amounts of fuel remaining in the separate reservoirs need to be equalized. Or, the ECM calculates the difference between the amounts of fuel remaining in the separate fuel tanks, and when the amount of fuel remaining in the sub fuel tank is larger than that of the main fuel tank, it drives the pump.The fuel from the fuel pump passes through the orifice inside the jet pump, and returns to the fuel ●

tank. When the fuel is passing through the orifice of the jet pump, a pressure difference develops around the orifice outlet port and it sucks the fuel out of the sub fuel tank (sub chamber), and that fuel is transferred to the main fuel tank (main chamber).

Fuel Transfer Operation

Fuel Pump

Chamber A Chamber B

Fuel Tank Solenoid Return Valve (OFF)

Jet Pump

Supply Pump

Engine

ECM

Fuel PCV Relay

F/PMP Relay


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Priming mode<2< In priming mode, the mode between the fuel transfer and the priming is changed by the fuel route ●

switching valve. During priming mode, the ECM turns on the PCV relay to energize the fuel route switching valve, changing the fuel feeding route, in which the fuel is fed from the fuel pump to the jet pump, to another route in which the fuel drawn by the fuel pump is fed to the supply pump. Priming mode can be activated by a driver’s switch operation at any time.

Fuel Pump

Chamber APriming Operation

Chamber B

Fuel Tank Solenoid Return Valve (ON)

Jet Pump

Supply Pump

Satellite Switch

Engine

ECM

Fuel PCV Relay

F/PMP Relay


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Priming operation using in-tank fuel pump: (LEXUS IS220d)To drive the in-tank fuel pump in priming mode, operate a satellite switch provided in the cockpit in the following procedure.

Check the fuel amount, and refuel when necessary. ●

Turn the engine switch ON. (IG ON) ●

Select PRIMING using the RH or LH button of the satellite switch. ●

Press the ON/OFF button of the satellite switch to start priming. ●

The priming operation will stop either when the ON/OFF button of the satellite switch is pressed or approximately two minutes have elapsed after the priming operation started. To activate the priming operation again, wait for several tens of seconds after stop.

ONOFF

“PRIMING” Mode

ON/OFF Switch

Satelite Switch

LH Switch RH Switch

TIP

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Circuit[[[

In-Tank Fuel Pump System Circuit<1<

Microprocessor

ECM

Fuel Route Switching Valve *

Fuel Pump

12 V

F/PMP

MAIN

FUEL PCV *

MREL

PPRM

FC

E1

BatteryM

Drive Circuit

Drive Circuit

* A relay (FUEL PCV) and fuel route switching valve are applied depending on the type of vehicle.

Drive Voltage<2< In-tank Fuel Pump Control ■


Value on Data List(In-tank Fuel Pump)FC

Relay Control OutputPPRM *

Relay Control OutputNormal

(Fuel pump not operated) 12V 12V OFF

Normal(Fuel transfer mode

activated)Below 1.5 V 12V ON

Normal(Priming mode activated)* Below 1.5 V Below 1.5 V ON

FC circuit open 0 V 12V Remains OFFFC circuit ground short 0 V 12V Remains OFF

PPRM circuit open * 12V 0 V Depends onPPRM circuit ground short * 12V 0 V Depends on

* Only on the LEXUS IS220d



Activate the Intank Fuel Pump Relay Activate in-tank fuel pump relay:ON/OFF


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8 Initialization and Registration11

Description11 The sensors and actuators will also change characteristics due to their own individual differences ●

and age deterioration. The ECM identifies the variations and changes to improve the sensor output accuracy and actuator operations, correcting them so that the vehicles can provide their best performance. The ECM judges the results of the actuator drive requests through the sensor signals, and then corrects the drive requests. Learning values are index parameters that allow the ECM to judge and correct the actuator drive requests.If the actuator operating conditions have changed significantly due to repair or parts replacement, the ●

ECM needs to identify the operating conditions of new sensors and actuators, and in order to conduct appropriate system controls corresponding to the engine operating conditions, some of the stored system control learning values will need to be manually updated or reset (initialized).If the engine has been operated without necessary learning value updates or initialization, the ●

amplitude of correction will be extremely large, therefore, the ECM may not be able to recognize the engine conditions precisely, or may not be able to drive the actuators accurately. Depending on the parts that are repaired or replaced, usually, the following operations are necessary: Learning sensor output individual differences, or transmitting stored leaning value data; Learning actuator individual differences, initializing learned values, or registering actuators; Transmitting stored learning value data from old ECMs.

Primary elements that are learned or registered in the ECD system ■System

component element

Learning/registration description Necessary operation

Monitor item[Data List/Utility]

Supply Pump

To increase the fuel pressure control accuracy, the ECM corrects variations due to the individual difference of pump discharging performance. Pump discharging performance gaps are calculated in the fuel pressure feedback control, the consequent value will be learned as correction values, and is stored in the ECM memory.

I n i t i a l i z a t i o n i s necessary when the following com-ponent par ts are changed:

Supply pump ●ECM ●

[Pump SCV Learning Value]

Fuel InjectorCompensation code(QR code)

The injectors have their own individual inject ion characteristics. To optimize the injection characteristics, the ECM corrects the individual differences by finely adjusting the injection durations of each injector through the compensation resistors or compensations codes.To use the compensation code injection correction, the 30-digit code (QR code) imprinted on the top of an injector needs to be registered in the ECM. The ECM identifies each injector's characteristics with the codes, correcting fuel injection.

Code registration ●is necessary when fuel injectors are changed.Code registration ●o r s t o r e d c o d e d a t a t r a n s m i s -sion is necessary when the ECM is changed.

Checking, saving and writing codes using an Intelligent Tester[Learning Values C o n f i r m a t i o n Utility]

Pilot Quantity Learning(Injection Volume Control) *1

To correct the engine individual differences and the fuel injection accuracy variations between the cylinders, the ECM performs injection with a minute amount of fuel while no fuel is injected, and estimates the actual amount of fuel injected by the injectors from the engine speed change caused by the minute volume fuel injection. The ECM learns a deviation between the values of an estimated actual injection volume and requested minute injection volume, and corrects the actual injection volume, removing the injection volume variations among the cylinders.

Value learning is ●necessar y when injectors or the en-gine is changed.L e a r n e d v a l u e ●d a t a t r a n s m i s -sion is necessary when the ECM is changed.

Checking, saving and writing learn-ing values using a n I n t e l l i g e n t Tester[Learning Values C o n f i r m a t i o n Utility]

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8 Initialization and Registration

System component

elementLearning/registration description Necessary

operationMonitor item

[Data List/Utility]

Crankshaft Position Sensor Plate *1

To increase pulse signal (NE signal) accuracy, the ECM learns the variations of the sensor plate tooth widths (pulse signal widths). The pulse signals are used to detect the crankshaft angle. When the accuracy of pulse signal widths is increased, the measurement accuracy of crankshaft rotation speeds also increases for idling, and over a wide range of the engine speed, from low to high. The crankshaft rotation speed is used to correct the injection volume variations between the cylinders.

Initialization is nec- ●essary when the crankshaft position sensor plate (en-gine) is changed.L e a r n e d v a l u e ●d a t a t r a n s m i s -sion is necessary when the ECM is changed.*2


VN Turbocharger(Step Motor Drive)

To increase the control accuracy of nozzle vane operation, the ECM learns the step motor 0 (zero) point position (vane fully closed position).The ECM corrects turbine f low amount variations through use of the turbine flow compensation resistor. The turbine flow compensation resistor is connected to the ECM, and the ECM reads the resistor value that indicates the turbocharger individual difference. The ECM uses the value as feedback in the boost pressure control.

Values are learned automatically.The turbine and com-pensat ion resistor are supplied as a set (assembly).

After the engine has warmed up, visually check the nozzle vane link-a g e m o v e m e n t when the engine is restarted.

VN Turbocharger(DC Motor Drive)

To increase the control accuracy of nozzle vane operations, the ECM learns the nozzle vane position sensor output transmitted immediately after the ignition switch is turned from off to on. The ECM stores the sensor output as the value indicating that the nozzle vanes are at the fully closed position. Hence, when the engine is stopped, the DC motor is driven to fully close the nozzle vanes (making them contact with the full close stopper) so that the vanes will be at the full close positions when the ignition switch is turned on next time.

Values are learned automatically.

V i s u a l l y c h e c k the nozzle vane linkage movement when the ignition switch is turned off.

EGR Valve

To increase the control accuracy of the EGR valve operation, the ECM learns the EGR valve position sensor output when the engine is cold or the EGR control is deactivated with the engine fully loaded. The ECM interprets the sensor output as a value indicating that the EGR valve is fully closed.


[EGR Close Learn Val.][EGR Close Lrn. Status]

Diesel Throttle Valve(Step Motor Drive)

To increase the control accuracy of diesel throttle operation, the ECM learns the following two throttle valve positions; one the fully closed position from a throttle full open switch ON signal, and the other the reference position while the engine is operating under specified conditions.


[Diesel Throttle Learn Status]

Diesel Throttle Valve(Rotary Solenoid)

To prevent the vibration from occurring when the engine is stopped, the throttle valve is fully closed. At this time, the ECM reads the throttle position sensor output, learning the throttle valve full close position.


[Diesel Throttle Learn Status][Throttle Close Learning Val.]

DPF/DPNR Catalyst *1

The ECM determines the heat developed in the catalyst according to the engine operating conditions (engine load), calculating heat deterioration values. To warn that the catalyst purification performance has been less effective due to severe heat deterioration, a DTC will be set when heat deterioration is detected.

Counter (calculation value) resetting (ini-tialization) is neces-sary when the DPF/DPNR catalytic con-verter is changed.

[DPF Catalyst Deteriorate]

Air-fuel Ratio Sensor *1

To increase the detection accuracy, the ECM learns the air-fuel ratio sensor output in the atmospheric air, eliminating sensor output variations. Using the learned value, the ECM corrects the fuel injection volume and EGR volume so that they come to the calculated target values.

Initialization is nec- ●essary when the air-fuel ratio sensor is changed.L e a r n e d v a l u e ●d a t a t r a n s m i s -sion is necessary when the ECM is changed.*2


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System component

elementLearning/registration description Necessary

operationMonitor item

[Data List/Utility]

Differential Pressure Sensor *1

The ECM corrects the measurement standard of the differential pressure sensors located before and after the catalytic converter that are used to measure the amount of PM trapped by (deposited on) the DPF/DPNR catalytic converter. The ECM learns the sensor outputs when the engine coolant temperature is higher than a certain level and the ignition switch is in the ON position while the engine is being stopped. The ECM interprets the sensor outputs as the value indicating that there is no pressure difference.


[Diff. Press. Sensor Corr.]

*1: Depending on the specifications, the component element is not applicable. Regarding the detailed value initialization and learning procedures, refer to the relevant TOYOTA repair manuals.

*2: When the ECM is replaced, if the learning value transmission is not completed properly due to voltage drops or other problems from any cause, DTC P1601 may be set and a default value will be set to prevent the DTC from being set again. The ECM will learn appropriate value in the subsequent engine control. In this case, check that no DTC is set.

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Part 2

Com

mon-rail D

iesel Engine

8 Initialization and Registration

Injection Volume Compensation21

Outline[1[ The injectors have their own individual injection characteristics. To correct the injection characteristics, ●

the ECM finely regulates the injection durations of each injector through use of the compensation resistors or compensations codes.Each injector injection characteristics are identified through the amount of fuel injected at a specified ●

point that is determined from the common-rail pressure and injection duration. When the ECM recognizes the compensation resistor or code preset in an injector itself, the injection volume of that injector can be corrected.The injection volume of an injector with a compensation resistor is corrected at between 2 to 4 points, ●

and for an injector with a compensation code, the injection volume is corrected at between 10 to 12 points. These correction points are determined through the common-rail pressure and injection duration.

Correction Resister Type Compensation Code TYpe (QR Code)

Correction Point

Common-rail pressure

Inje

ctio

n Q

uant

ity

Inje

ctio

n Q

uant

ity

Activation Pulse Correction TQ Activation Pulse Correction TQ

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Part 2

Com

mon-rail D


Compensation Resistor Type Injector[2[ In a system, where the injectors are equipped with the compensation resistor, the resistors are directly ●

connected to the ECM, and the ECM reads the resistor values, correcting the injection volumes.

Correction ResistorCorrection Resistor

Solenoid CoilInjector

EDU

ECM

Compensation Code (QR Code) Type Injector[3[ The QR code and its alphanumeric version code (30-digit alphanumeric code), which represent the ●

injection characteristics, are imprinted on the top of the head of an injector. The common-rail system optimally regulates the injection volumes using the information. When new injectors are fitted onto the engine, their compensation codes are need to be entered the ECM using an Intelligent Tester.The injection volume correction points, which are determined from the common-rain pressure and ●

injection duration, vary depending on the vehicle models and engine types.

QR Code

Laser Marking

Injector Compensation Code

Part 3

Effective Use of Intelligent Tester

307

308

Part 3


1 Description

Part 3 Effective Use of Intelligent Tester

This chapter describes the ECM data items that can be shown on a TOYOTA Intelligent Tester and actuator items that can be arbitrarily driven.

1 Description4

The ECM receives a signal that contains driving condition information from the sensor. The ECM ●

recognizes and judges the signal and then outputs a signal that regulates the actuator to operate in correspondence to the driving conditions.The various control values that are processed inside the ECM are the ECM data, and these can be ●

checked by an Intelligent Tester. (Data List function)The actuator can be arbitrarily driven by outputting the drive request signal from an Intelligent Tester ●

to the ECM and thus the operation conditions can be checked by monitoring the ECM data. (Active Test function)

Sensor SwitchActuator

Drive Request (Active Test)

ECM data (Data List)

ECM

Recognize Judge Drive

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Part 3


2 Data List

2 Data List5

Outline11

Signals Shown in Data List[1[ Data List is a function to check the “input signals from the sensor”, “output signals to the actuator” and ●

“various learning values” that are necessary for the ECU control in the form of ECU data.The control data can be checked without touching various parts of the vehicle. And especially for the ●

input signal system, it can be judged to be normal without conducting the individual inspections and wireharness inspection, when the ECU data inspection result is normal.In addition, the items that cannot be checked from outside, such as ECU learned conditions, can be checked.Data List is generally classified as the following ECM data item groups; “input signals”, “output signals” ●

and “learning values”.

Input signals Output signals Learning valuesSignals from the sensorsSignals sent to the ECM from various sensors and switchesThe operation conditions of vari-ous systems and driving condi-tions are sent to the ECM.

Signals to the actuatorSignals that inform the ECM how to act against the actuator.

Value for compensation to gain current best vehicle conditions in accordance with the individual differences of the sensors and ac-tuators and the characteristic changes over time recognized by the ECM.

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2 Data List

Data List Items[2[ Using the Data List function, data from the following systems can be shown in the details of the data ●

list items.

Category DescriptionAccelerator Pedal Accelerator pedal position sensor related data

Air-fuel Ratio Sensor Air-fuel ratio sensor related dataCharging Control Charging control system related data

Check Mode ECM mode related dataCommon-rail Injection Fuel injector and injection volume related data

Diagnosis DTC detection related dataDiesel Throttle Diesel throttle control related data

ECT Electric controlled transmission (transaxle) related dataEGR Exhaust Gas Recirculating system related data

Exhaust Exhaust system and catalyst related dataFuel Fuel pressure related data

Monitor Data related to monitor status in compliance with legal regulationsOther Systems Status data of other systems related to the engineSensor / Status Sensor input and engine condition information

Switch Status signal data from various switchesSymptom Diagnosis Vehicle motion information

Test Cylinder compression measurement (active test) informationVN Turbocharger Turbocharger control related data

Vehicle Specifications Vehicle specification information

REFERENCE This manual describes the Data List items by dividing them into the above categories to improve ●

searchability.However, Intelligent Testers can show the data list items in various measurement groups, such as All ●

Data, Custom List*, Primary* and some defined measurement groups.

* Custom List: Measurement group that is arbitrarily selected by the tester user* Primary: Measurement group that is set for basic engine inspection

Even on the engine types that have data list items, they may not be displayed depending on the vehicle model and model year.

NOTICE

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2 Data List

Details of Data List Items21

Cat-egory

Tester Display Indication Summary Diagnostic Notes

Acc

eler

ator

Ped

al

Acc

el P

ositi

onMeasurement Item Hint

Accelerator position status for engine control This parameter indicates the final accelerator pedal open-ing angle calculated by the ECM.

Min: 0 Max: 100 Unit: % Reference Value

Cause of Out of Range0 % for a non depressed accelerator pedal and 100 % when fully depressed, value is in proportion with the ac-celerator pedal opening angle regardless of the engine condition

Under fail-safe condition for END system1. Accelerator position sensor malfunction2. W/H or connector3. ECM4.

Acc

ele

Sen

sor O

ut N

o.1

Measurement Item Hint

No.1 Accelerator pedal position sensor volt-age

When the circuit is open or a short occurs, output is less than 1.2 V or grater than 4.8V .If both No.1 and No2 circuits open or short occurs use the fail safe value and fix the engine speed at first idle.

Min: 0 Max: 5 Unit: V Reference Value

Cause of Out of Range Approx. 0.8 V for a non depressed accelerator pedal and 3.5 V when fully depressed, value is in proportion with the accelerator pedal opening angle regardless of the engine condition.The gap between Accele Sensor Out No.2 is constantly 0.8 V

Under fail-safe condition for ECD system1. Accelerator position sensor malfunction2. W/H or connector3. ECM4.

Acc

ele

Sen

sor O

ut N

o.2


No.2 Accelerator pedal position sensor volt-age

When the circuit is open or short occurs, output is less than 1.2V or grater than 4.8 V.Both No.1 and No2 circuits open or short occurs use the fail safe value and fix the engine speed at first idle.


Cause of Out of Range Approx. 1.6 V for a non depressed accelerator pedal and 4.3 V when fully depressed, value is proportion with ac-celerator pedal opening angle regardless of the engine condition.The gap between Accele Sensor Out No.1 is constantly 0.8 V


Acc

ele

Sen

s N

o.1V

olt %


No.1 Accelerator pedal position sensor out-put

This indicates the value of No.1 Accelerator pedal position sensor voltage divided by sensor power source voltage (VC)


Cause of Out of RangeApprox. 16% at non depressed accelerator pedal and 70% at fully depressed accelerator pedal, value is proportion with accelerator pedal opening angel regardless engine condition.


Acc

ele

Sen

s N

o.2V

olt %


No.2 Accelerator pedal position sensor out-put

This indicates the value of No.2 Accelerator pedal position sensor voltage divided by sensor power source voltage (VC)


Cause of Out of RangeApprox. 32% at non depressed accelerator pedal and 85 % at fully depressed accelerator pedal, value is proportion with accelerator pedal opening angel regardless engine condition.


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Part 3


2 Data List

Cat-egory


Air-

fuel

Rat

io S

enso

r

AF

Lam

bda

B#S

#


Lambda value calculated from the air-fuel ratio sensor14.5 is 1.000B#S# represents the sensor location

AF Lambda B#S# = air-fuel ratio / 14.5 (Stoichiometric A/F ratio)Value less than 1 (0.000 to 0.999): RichValue greater than 1 (1.001 to 1.999): LeanAir-fuel ratio = Intake air mass / (main fuel injection + ex-haust fuel addition injection mass)Refer to the illustration A.

Min: 0 Max: 1.99 Unit: N/A Reference Value

Cause of Out of Range0.80: 11.8 (Rich)0.90: 13.2 (Rich)1.00: 14.5 (Stoichiometric air-fuel ratio)1.10: 16.2 (Lean)1.20: 17.6 (Lean)

Air-fuel ratio sensor1. Wire harness or connector2. Fuel injector3. E x haus t f ue l add i t i on i n j ec to r ( i f 4. equipped) ECM5.

AF

Sen

sor L

earn

ing

Valu

e


AF sensor output voltage learning value in the atmospheric air

AF sensor output voltage learning value in atmospheric air.To correct variations caused by the individual differences of the outputs or deterioration by age, the ECM learns the air-fuel ratio sensor output value in the atmospheric air.


Cause of Out of Range AD series engine reference value:1.8 to 2.1 V

Initial value in case of learning error 1.9994 V

Air-fuel ratio sensor1. Wire harness or connector2. ECM3.

AFS

Cur

rent

B#S

#


Air-fuel ratio sensor output current valueB#S# represents the sensor location

Output current increases as the air-fuel ratio becomes larger (lean)

Min: -128 Max: 127.99 Unit: mA Reference Value

Cause of Out of RangeIdling after engine warmed-up: -0.5 to 0.5 mA

Air-fuel ratio sensor1. Wire harness or connector2. ECM3.

AFS

Vol

tage

B#S

#


Air-fuel ratio sensor output voltage valueB#S# represents the sensor location

If the exhaust fuel addition injector is clogged, even if DPF/DPNR catalyst regeneration is performed with the intelligent tester, the AFS B1 S1 value will not change.Refer to the illustration A.


Cause of Out of Range

Idling after engine warmed-up: 1.01 to 1.58 V

Air-fuel ratio sensor1. Wire harness or connector2. Fuel injector3. E x haus t f ue l add i t i on i n j ec to r ( i f 4. equipped) ECM5.

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2 Data List

Cat-egory


Air-

fuel

Rat

io S

enso

rIllustration A

Air-fuel Ratio Displayed on Tester:

AF Lambda B1S1 = Air-fuel Ratio /14.5

AF Lambda B1S1

AFS B1S1

2

2

1

1

0

0

(V)

Air-fuel Ratio14.5

20 30 40 50

AFS Voltage B1S1 - - - 0 0.065 0.174 0.274 0.361 0.513 0.787 1.013 1.579

AF Lambda B1S1 0.828 0.897 0.966 1 1.034 1.103 1.172 1.241 1.379 1.724 - -

Air-fuel Ratio 12 13 14 14.5 15 16 17 18 20 25 30 50

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2 Data List

Cat-egory


Cha

rgin

g C

ontro

l

Bat

tery

Cur

rent


Shows the current value calculated from the current sensor output

When driving after the engine is warmed-up, the values change in accordance with the amount of electricity gen-erated by the alternator.In case of overcharge or over discharge, the charging control will be stopped to protect the battery and prevent capacity decrease

Min: -100 Max: 100 Unit: A Reference Value


During vehicle acceleration: small currentDuring vehicle deceleration: large currentWhile battery discharged: negative value

Battery current sensor1. Wire harness or connector2. Charging system (Alternator)3. Battery 4. ECM5.

Bat

tery

Tem

pera

ture


Displays the battery fluid temperature calcu-lated from the fluid sensor (current sensor) output

Charging control is performed in accordance with the sen-sor temperature signals because the current reception characteristics change in accordance with the battery fluid temperature

Min: -45 Max: 156.4 Unit: ˚C Reference Value


The values change in accordance with the actual tem-perature around the battery

Battery current sensor1. Wire harness or connector2. Charging system (Alternator)3. Battery4. ECM5.

Alt

Vol -

Act

ive

Test Measurement Item Hint

Voltage command value to the regulator dur-ing Active Test [Control the Voltage of the Alternator]

Active test support dataEngine is operated


Cause of Out of Range Changes in accordance with commands during Active Test-

Alt

Vol -

Non

Act

ive

Test


Voltage command value to the regulator dur-ing Active Test [Control the Voltage of Alter-nator] (normally operated)

Active test support dataEngine is operated


Cause of Out of Range The values change in accordance with the battery fluid temperature and driving conditions (12.5 to 14.8 V)-

Cat-egory


Che

ck M

ode

Che

ck M

ode


Check mode status Check Mode: The mode in which certain DTCs can be de-tected more easily and with higher sensitivity.

Status ON/OFF Unit: N/A Reference Value

Cause of Out of RangeON: Check mode selected

ECM

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Part 3


2 Data List

Cat-egory


Com

mon

-rai

l Inj

ectio

n

Inje

ctio

n Fe

edba

ck V

al C

yl#


Injection compensation value between cylin-ders:Rotational fluctuation compensation injec-tion volume during idling (calculated from the crankshaft rotation speed)4 cylinder engine:#1 → No. 1 cylinder, #2 → No. 2 cylinder#3 → No. 3 cylinder, #4 → No. 4 cylinder8 cylinder engine:#1 → No. 1 cylinder, #2 → No. 2 cylinder#3 → No. 6 cylinder, #4 → No. 7 cylinder#5 → No. 3 cylinder, #6 → No. 4 cylinder#7 → No. 5 cylinder, #8 → No. 4 cylinder

When compensation is performed before a malfunction occurs, it is not always caused by a problem with the cyl-inder with the biggest absolute numberExample: When the injection order is 1-3-4-2#1 Compression leak → #1 rotation speed becomes low and #2 rotation speed becomes high#2 Injection volume excessive → #2 rotation speed be-comes high

Min: -10 Max: 10 Unit: mm3/st Reference Value


Idling: -3.0 to 3.0 mm3/st

Positive value if rotation speed of each cylinder combus-tion process is lower than the target rotation speed cal-culated from the target idling speed, and negative value if higher.

Injector clogging1. Injector deterioration2. Decrease in cylinder compression3. Injector compensation code is incorrectly 4. set (forgot to input code after replace-ment or made mistake during setting of code after replacing ECM with one from another vehicle)

Inje

ctio

n P

ress

ure

Cor

rect

ion


Injection pressure feedback correction amount: Injection volume correction when there is difference between the calculated injection volume fuel pressure and the actual fuel pressure

When this value (absolute value) is large, it shows that the difference between the actual fuel pressure and the target fuel pressure is large. A positive value shows that the amount of fuel compressed and fed has increased due to lack of pressure. A negative value shows that the amount has decreased due to excessive pressure. When the pump SCV malfunctions, the rail pressure usually be-comes excessive due to SCV closure malfunction and this value and the pump individual difference learning value becomes smaller.

Min: -400 Max: 400 Unit: mm3/st Reference Value

Cause of Out of Range -20 to 20 mm3/st at standard temperatureBasically, if the actual fuel pressure = target fuel pressure, the injection pressure feedback compensation amount = 0.

Suction control valve malfunction1. Clogged fuel filter2.

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2 Data List

Cat-egory


Com

mon

-rai

l Inj

ectio

n

Inj V

ol F

eedb

ack

Lear

ning


Injection volume compensation learning value: Injection volume compensation value for reaching the target idling speed at the cur-rent engine status using the injection volume at the minimum engine friction (Idle Injection Volume [Min])

“ Inj Vol Feedback Learning” is calculated by the ●deviation of the injection volume at idle speed when the engine has warmed up.When poor quality fuel or sustained low-speed driving ●causes a reduction in the injector nozzle hole area (reducing injection volume), the “Inj Vol Feedback Learning” will become an abnormal value (for example, 2.0 mm3/st). At the time if all of “Injection Feedback Value #” are within specifications (for example, less than 2 mm3/st), then all cylinders are considered to be malfunctioning.Other than the injectors, fuel f ilter pore blockage, ●poor-quality fuel, compression loss and large engine friction can all cause “Inj Vol Feedback Learning” to be abnormal.When the engine is started in cold conditions, the ●idling engine speed is high and gradually slows down in accordance with the increasing engine coolant temperature. If the changing value of the idling engine speed is unstable during engine warming up, check “Inj. FB Vol. For Idle”.When combustion noise or drivability is bad, check “Inj ●Vol Feedback Learning” as part of the injection system deterioration diagnosis.Only when the ignition switch is turned off, the learned ●value is updated gradually.Refer to illustration B. ●

Min: -10 Max: 9.92 Unit: mm3/st Reference Value


Idling: -2.0 to 2.0 mm3/stFuel injector1. Engine assembly (low compression, 2. large engine friction, etc.)

Inj.

FB V

ol. F

or Id

le


Idling stable condition injection volume com-pensation learning value:Compensation injection volume when there is dif ference between the target engine speed and the actual engine speed while idling

When the electric load or the AC SW is ON, compensa-tion is performed respectivelyCompensation amount is the total amount for all cylinders

Min: -80 Max: 79.998 Unit: mm3/st Reference Value


Idling: -10 to 10 mm3/stFuel injector1. Fuel filter2. Inferior quality fuel3. Engine assembly (low compression, 4. large engine friction, etc.)

Inje

ctio

n Vo

lum

e



Injection amount for each combustion. ●If injectors are clogged, fuel quality is poor, the fuel filter ●is clogged, or engine friction increases, the “Injection Volume” will increase.If there is a malfunction due to low turbocharger ●pressure or a low intake air volume, the injection volume is limited and there is a lack of power.

Min: 0 Max: 100 Unit: mm3/st Reference Value


Idling: 3.0 to 10.0 mm3/stFuel injector1. Fuel filter2. Inferior quality fuel3. Engine assembly (low compression, 4. large engine friction, etc.)

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2 Data List

Cat-egory


Com

mon

-rai

l Inj

ectio

n

Inje

ctor

Mem

ory

Err

or


Displays the ECM error status when the injector QR is unregistered or unable to be read outDisplays the QR code writing error status

This flag displays an error when the injector compensa-tion code is not input for a new ECU or an injector for a different type or a value beyond the compensation setting range is input. This error will not be detected when a wrong QR is input.For unregistered ECU, check engine light will illuminate.On certain models, P1601 will be displayed

Status No error / Error Unit: N/A Reference Value

Cause of Out of RangeNo error

QR code writing error

Idle

Inje

ctio

n Vo

lum

e (M

in)


Reference value for calculating the injection volume compensation learning value “Inj Vol Feedback Learning”

The injector flow amount decrease can be diagnosed by comparing the value with the injection volume command value when idling without an electric load after the engine is warmed-up.When the “Inj Vol Feedback Learning” has been in-creased to 1.5 to 2.0 mm3/st when the travel distance is short (10,000 to 20,000 km), the flow amount may have decreased due to a clogged injector, bad fuel etc.Refer to illustration B

Min: 0 Max: 39.8 Unit: mm3/st Reference Value

Cause of Out of Range 3.0 to 10 mm3/stInjection volume compensation is determined from the result of the Inj Vol Feedback Learning-

Mai

n In

ject

ion

Perio

d


Main injection period

When unable to start, whether the injection is conducted ●is checked.When the fuel pressure falls to 15 MPa or less, “Main ●Injection Period” is set to 0.When P0093, P0607, P0627, P062D or P062E is ●stored, there is an engine stall request. At that time, “Main Injection Period” equals 0.As the engine stalls 1 minute after the MIL illuminates, ●freeze frame data cannot be checked.

Min: 0 Max: 65535 Unit: μs Reference Value


Idling, engine warmed up:490 to 690 µs (1VD reference value)170 to 368 μs (2AD reference value)

ECM (Calculation items related to the in-1. jection volume control)Fai l -safe due to DTC (DTC P0093, 2. P0607, P0627, P062D, P062E, etc.) de-tection

Mai

n In

ject

ion

Tim

ing Measurement Item Hint

Main injection timingUse “Main Injection Timing” to check poor drivability when the following symptoms are present: Bad injection timing, black smoke, and white smoke.

Min: -90 Max: 90 Unit: °CA Reference Value

Cause of Out of Range Idling after engine warmed up and vehicle under normal atmospheric pressure:-5 to 15 °CA

ECM (Calculation items related to the in-1. jection timing control)

Pilo

t 1 In

ject

ion

Perio

d Measurement Item Hint

Pilot 1 injection timing Check to see if “Pilot 1 Injection Period” is not zero when the symptoms occur.


Cause of Out of RangeIdling: 0 µsECM (Calculation items related to the 1.

multiple injection control)

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Part 3


2 Data List

Cat-egory


Com

mon

-rai

l Inj

ectio

n

Pilo

t 1 In

ject

ion

Tim


Pilot 1 injection timingUse “Pilot 1 Injection Timing” to check poor drivability when the following symptoms are present:Bad injection timing, black smoke, and white smoke.


Cause of Out of RangeIdling after engine warmed up and vehicle under normal atmospheric pressure: 0 °CAECM (Calculation items related to the 1.


Pilo

t 2 In

ject

ion

Perio

d Measurement Item Hint

Pilot 2 injection timing Check to see if “Pilot 2 Injection Period” is not zero when the symptoms occur.


Cause of Out of Range Idling after engine warmed up: 390 to 490 µs (1VD reference value)148 to 260 µs (2AD reference value)

ECM (Calculation items related to the 1. multiple injection control)

Pilo

t 2 In

ject

ion

Tim


Pilot 2 injection timingUse “Pilot 2 Injection Timing” to check poor drivability when the following symptoms are present: Bad injection timing, black smoke, and white smoke.


Cause of Out of RangeIdling after engine warmed up and vehicle under normal atmospheric pressure: -6 to -2 °CAECM (Calculation items related to the 1.


Afte

r Inj

ectio

n Pe

riod Measurement Item Hint

After Injection PeriodCheck to see if “After Injection Period” is not zero when the following symptoms occur:Black smoke, poor drivability.


Cause of Out of Range 2000 rpm with no load: 300 to 370 µs (1VD reference value)90 to 110 µs (2AD reference value)

ECM (Calculation items related to the 1. multiple injection control)

Afte

r Inj

ectio

n Ti

min

g Measurement Item Hint

After injection timingUse “After Injection Timing” to check poor drivability when the following symptoms are present: Bad injection timing, black smoke, and white smoke.


Cause of Out of Range2000rpm with no load: 23 to 30°CAECM (Calculation items related to the 1.


Pilo

t Qua

ntity

Sta

te


Pilot quantity learning status

When the learning is incomplete, the MIL comes ON and P1601 EEPROM error will be recordedWhen replacing injectors or ECUs, use an intelligent tes-ter to perform learning.

Status Standby / Wait / Learn / Stop / Complete Unit: N/A Reference Value

Cause of Out of Range Standby: Not performed (pilot quantity learning manual mode standby)Wait: Waiting for the learning activation conditions to be metLearn: Learning is performedStop: Learning is stoppedComplete: Learning is complete

-

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Part 3


2 Data List

Cat-egory


Com

mon

-rai

l Inj

ectio

n Pilo

t Qua

ntity

Sta

te (C

AT)


Pilot quantity learning prohibition state

Displays the pilot quantity learning prohibition state due to the after-treatment control. Catalyst regeneration control being previously completed because learning cannot be performed under following conditions:

Catalyst regeneration control (PM combustion) was ●performed D iese l ox idat ion cata ly t i c conver ter / f i l te r bed ●temperature rise prevention control is performed (DPF/DPNR)Air- fuel rat io sensor atmospher ic air learning is ●performed.

Pilot quantity learning needs to be performed after re-placing the injector, however learning is prohibited during DPF/DPNR catalyst regeneration control because it can-not be conducted properly during regeneration control.

Status READY / NG Unit: N/A Reference Value

Cause of Out of RangeREADY:Catalyst regeneration control not performed

Learning may not have been performed us-ing an intelligent tester after replacing the injector or ECM

Illustration B

320

Part 3


2 Data List

Cat-egory


Dia

gnos

is

# C

odes

(Inc

lude

His

tory

)


Number of detected DTCs

The applicable Diagnostic Trouble Codes (DTCs) are stored in the ECM memory when the vehicle on-board computer detects a malfunction in the computer itself or in drive system components. In addition, the Malfunction Indicator Lamp (MIL) is illuminated.Number of DTCs appearing at least once during the last 40 times the vehicle was warmed up.

Min: 0 Max: 255 Unit: N/A Reference Value


0: System normalThe vehicle on-board computer (ECM) de-tects a malfunction in the common-rail diesel engine control system

MIL


Malfunction Indicator Lamp (MIL) statusThe MIL is illuminated when the vehicle onboard comput-er detects a malfunction in the computer itself or in drive system components.



OFF: System normalThe vehicle on-board computer (ECM) de-tects a malfunction in the common-rail diesel engine control system

Dis

tanc

e fro

m D

TC

Cle

ared


Distance after DTC cleared

Distance driven since the DTCs were cleared. ●(Data List’s “Distance from DTC clear”) - (Freeze frame ●data’s “Distance from DTC clear”) = Distance driven since the abnormality occurred.

Min: 0 Max: 65535 Unit: km Reference Value

Cause of Out of Range-

-

MIL

ON

Run

Dis

tanc

e


Distance after DTC stored

Distance traveled after a DTC is stored. ●Cleared when the negat ive (-) bat ter y cable is ●disconnected or when the DTC is cleared using the intelligent tester.Result of ECU calculations (using the vehicle speed) ●

Min: 0 Max: 65535 Unit: km Reference Value


-

Num

ber o

f E

mis

sion

DTC


Number of DTCs related to the emission de-terioration -



-

OB

D R

equi

rem

ents Measurement Item Hint

Identifying OBD requirement -

Min: E-OBD / Euro 4 / Euro 5 / NO Unit: N/A Reference Value

Cause of Out of Range Euro-OBD applicable country models:E-OBD -

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Part 3


2 Data List

Cat-egory


Dia

gnos

is

Run

ning

Tim

e fro

m M

IL

ON


Running time after MIL turns on

Engine run time since the MIL illumination. ●Cleared when the negat ive (-) bat ter y cable is ●disconnected or when the DTC is cleared using the intelligent tester.

Min: 0 Max: 65535 Unit: min Reference Value


-

TC a

nd T

E1


TC and TE1 terminal of DLC3When the Active Test “Connect the TC and TE1” is per-formed, the system behaves as if TC and CG were con-nected.

Status ON / OFF Unit: N/A Reference Value

Cause of Out of RangeOFF: TC and TE1 are not connected

-

Tim

e af

ter D

TC

Cle

ared


Time after DTCs cleared Time elapsed since the DTCs were cleared (or shipment from the factory).

Min: 0 Max: 65535 Unit: min Reference Value


-

War

mup

Cyc

le

Cle

ared

DTC


Number of engine warm ups since DTCs were cleared.

(Data List “Warmup Cycle Cleared DTC”) - (Freeze frame data “Warmup Cycle Cleared DTC”) = Warmup cycles since the abnormality occurred.



-

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Part 3


2 Data List

Cat-egory


Die

sel T

hrot

tle

Act

ual T

hrot

tle P

ositi

on #


Actual diesel throttle valve opening degree# represents the bank

Closing percentage of the throttle valve.Fully closed: 100%. ●Fully open: 0%. ●

There is no connection with the accelerator. However, un-der full load, the throttle is usually fully open (0%).

Stuck closed: Engine stall, difficult to start, lack of ●power, black smoke, rough idleStuck open: Loud turbocharging sound, bad vibration ●when engine stoppedWhen ECM detects a malfunction in the diesel throttle ●(MIL on), engine power is restricted so that the vehicle can drive at a maximum speed of 80 to 120 km/h.

Min: -20 Max: 120 Unit: % Reference Value


Idling after engine warmed-up: 0 to 90%(accordance with EGR control condition)

Diesel throttle body (stuck open, stuck 1. closed)Diesel throttle valve position sensor 2. Wire harness or connector3. ECM4.

Die

sel T

hrot

tle L

earn

S

tatu

s #


Diesel throttle valve full closed position learning status# represents the bank

If the system is functioning properly, learning will be ●performed when the engine switch is turned from on (IG) to off.NG indicates that a foreign object may be lodged in the ●throttle valve or actuator components, or a disconnect/short exists in the signal wires.

Status NG / OK Unit: N/A Reference Value


OKDiesel throttle body (stuck open, stuck 1. closed)Diesel throttle valve position sensor2. Wire harness or connector3. ECM4.

Thro

ttle

Clo

se L

earn

ing

Val.

#


Diesel throttle valve full closed position learning value# represents the bank

When the engine is turned from on (IG) to off and 5 ●seconds elapse, learning of “Throttle Close Learning Val.” will be complete.When “Throttle Close Learning Val.” is outside of the ●normal range, a foreign object may lodged in the throttle valve.

Fully closed: 17.25 deg.Fully open: 87.25 deg.

If the value is stuck at the upper limit of 21.25 deg, there ●is a chance that a malfunction is present.

However, as the initial value for the learned value is 21.25 deg, it is necessary to check the value after learning is completed.

Min: 0 Max: 249.992370605468 Unit: deg Reference Value


14 to 22 deg(rotary solenoid drive diesel throttle valve reference value)


323

Part 3


2 Data List

Cat-egory


Die

sel T

hrot

tle

Thro

ttle

Mot

or D

UTY

#


Diesel throttle motor actuate duty ratio# represents the bank

To 0%: Closed side diesel throttle actuation. ●To 100%: Open side diesel throttle actuation. ●When this value is large but the actual opening angle ●does not reach the target opening angle, there is an unable to close malfunction.If it is small, but the actual opening angle does not reach ●the target opening angle, there is an unable to open malfunction.Usually this value is at approximately 50 +/-20%, but ●momentarily jumps outside this range do occur.If a duty outside 50 +/-40% continues for several ●seconds, it will be judged that the diesel throttle is not moving properly and the MIL will be illuminated.

If the duty ratio does not remain constant when the target throttle position is constant, the mechanical movement of the throttle valve is unsmooth.



Idling after engine warmed-up: 10 to 90%Diesel throttle body (stuck open, stuck 1. closed) Wire harness or connector2. ECM3.

Thro

ttle

Ste

p P

ositi

on


Diesel throttle valve position for step motor type

The ECM learns the valve position by detecting the full open position using the diesel throttle valve full open switch and determines the full open and full closed steps and recognizes the position by the steps.Fully open: 0 stepFully Closed: 209 (217) step

Min: 0 Max: 255 Unit: step Reference Value

Cause of Out of RangeIdling after engine warmed up:150 to 175 step

Diesel throttle body (step motor) 1. Wire harness or connector2. ECM3.

Thro

ttle

Sen

sor #

Vol

t %


Diesel throttle valve position sensor output# represents that there are 2 sensor output systems.Displayed in % by dividing the No. 1 throttle sensor output value by the sensor power voltage.Displayed in % by dividing the No. 2 throttle sensor output value by the sensor power voltage.

Throttle position sensor output voltage is converted ●using 5 V = 100%.When fully closed: 14%. ●When fully open: 70%. ●When the ignition switch is turned from OFF to ON, the ●throttle valve fully opens once.When the ignition switch is turned from ON to OFF, the ●throttle valve fully closes once.

Symptoms when out of range:Stuck closed: Engine stall, difficult to start, rough idling, ●lack of power, black smoke, white smokeStuck open: Loud turbocharging sound, bad vibration ●when engine stoppedWhen the ECM detects a malfunction with the diesel ●throttle (MIL on), engine power is restricted but city driving is possible.



Ignition switch on: 60 to 80% ●Warmed-up and idling: 10 to 80% ●


324

Part 3


2 Data List

Cat-egory


Die

sel T

hrot

tle

Targ

et T

hrot

tle P

ositi

on #


Target diesel throttle valve opening degree# represents the bank

If the actual throttle position follows this value, it is normal.Fully closed: 100%Fully open: 0%The value should not largely differ from the actual throttle position


Cause of Out of RangeIdling after engine warmed-up: 0 to 90%(accordance with EGR control condition)ECM (Calculation items related to the diesel

throttle control)

Cat-egory


ECT

Rec

eive

d M

IL fr

om E

CT Measurement Item Hint

Malfunction information from transmission control ECU

Information through CAN communicationOFF: No MIL ON command from the ECTON: MIL ON command from the ECT


Cause of Out of RangeOFF: ECT system is operating normallyMalfunction in ECT (electronic controlled

transmission) system

Shi

ft P

ositi

on S

ig fr

om

ECT


Transmission gear position signal from transmission control ECU Information through CAN communication

Status 1st / 2nd / 3rd / 4th / 5th / 6th Unit: N/A Reference Value

Cause of Out of RangeAccordance with transmission gear positionMalfunction in ECT (electronic controlled


ECT

Lock

Up


Automatic transmission lock-up statusInformation through CAN communicationOFF: Lock-up OFFON: Lock-up ON


Cause of Out of RangeAccordance with transmission lock-up statusMalfunction in ECT (electronic controlled


325

Part 3


2 Data List

Cat-egory


EGR

Act

ual E

GR

Val

ve P

os.#


Actual EGR valve opening#represents the bankCalculated from EGR valve opening position sensor

Fully open: 100%. ●Fully closed: 0%. ●Inspect while comparing to “Target EGR Valve Pos.”. ●Check the valve movement via the Active Test. ●Sometimes the malfunction only occurs around a certain ●temperature, so refer to the engine coolant temperature and outside temperature at the time the malfunction occurred.

“Actual EGR Valve Pos. #2” has to be inspected while comparing to “Target EGR Valve Pos. #2”.



Idling after engine warmed up: 0 to 80%(accordance with EGR control condition)

EGR valve1. EGR valve lift sensor2. Wire harness or connector3. ECM4.

EGR

VS

V


EGR operation status for vacuum controlled EGR valve

Active test support dataDisplays ON when the E-VRV drive duty ratio is 45% or more



ON: Active Test item “Control the EGR System” operatedE-VRV1. EGR valve2. Wire harness or connector3. ECM4.

EGR

Clo

se L

earn

Val

.EG

R C

lose

Lrn

Val

. #


EGR valve full closed position learning value# represents the bank

This value is the EGR position sensor output voltage. ●At the upper and lower limits of the normal range, it is ●possible that a foreign object is lodged in the EGR valve seat area.As the lower and upper limits are 3.5 V and 4.5 V ●respectively, if the value becomes stuck at either of these values, there is a malfunction in the lift sensor or the valve position may be misaligned (foreign matter is present, etc.).


Cause of Out of RangeIdling: 3.5 to 4.5 VInitial value 4.0 V when the battery terminal is reconnect-ed

EGR valve (carbon deposits, stuck open)1. EGR valve lift sensor2. Wire harness or connector3. ECM4.

EGR

Clo

se L

rn. S

tatu

s


EGR valve full closed position learning sta-tus

“OK” means the fully closed position learning has ●completed normally.When NG, the learned fully closed position may be ●outside of the normal range. When NG, there may be foreign matter stuck in the valve.After disconnecting and reconnecting the battery cable, ●if the ignition switch has not been turned to off once, learning may not be completed.



OK: Full closed position learning completeEGR valve (carbon deposits, stuck open)1. EGR valve lift sensor2. Wire harness or connector3. ECM4.

326

Part 3


2 Data List

Cat-egory


EGR

EGR

Lift

Sen

sor O

utpu

t #


Displayed in % by dividing the sensor output value by the sensor power voltage# represents the bank

EGR lif t sensor output is calculated from the EGR ●position sensor output voltage. Value is 0 to 5 V converted to 0 to 100%.Sensor output may vary depending on the engine ●

There are 2 types, one with the lift sensor voltage around 0 V and the other around 5 V at the closed side

Except for the engines without the opening degree ●feedback, the EGR valve may be malfunctioning if the difference between the value and the target EGR valve opening degree is larger than the predetermined value.

Min: 0 Max: 99.6 Unit: % Reference Value

Cause of Out of RangeFully closed: 80 +/- 10%Fully opened: below 26 +/- 10%(AD series engine reference value)

EGR valve (carbon deposits, stuck open)1. EGR valve lift sensor2. Wire harness or connector3. ECM4.

EGR

Ope

ratio

n P

rohi

bit


EGR valve forced drive prohibition status

OK: Status when the EGR valve can be forcibly driven.NG: Status when it cannot be forcibly driven. When the engine is running, the Active Test of [Control the EGR Step Position] can operate the EGR valve only to the closing side.When the engine is not running (ignition switch ON), the Active Test can operate the EGR valve to both the open and closing sides.



OK: Active Test item “Control the EGR Step Position” can be performed

Following execution conditions for the active test are not met.

Ignition switch ON1. Vehicle stopped condition2. Engine stopped (opening direction drive 3. is restricted when the engine is running)

Targ

et E

GR

Pos

. #


ECM calculated target EGR valve opening degree# represents the bank

ECU calculated value based on sensors (airflow, boost pressure, intake air temperature etc.)

Fully open: 100%. ●Fully closed: 0%. ●When value is out of range and approaching 0%: MAF ●meter degradation, intake or exhaust system blockageWhen value is out of range and approaching 100%: ●EGR pipe blockage


Cause of Out of Range Idling after engine warmed up: 0 to 80%Changes in accordance with the engine operating condi-tions15 to 35% (2AD-FHV reference value)

ECM (Calculation items related to the 1. EGR control)

EGR

Ste

p P

ositi

on


Current EGR valve opening degree for the step motor

The step motor is controlled in up to 58 incremental steps (converted for 2 phase excitation), with a stroke of 4.3mm between the full close to full open positions. The ECM de-termines the number of steps for the fully closed condition by full closed position learning and recognize the valve position by the steps.Fully open: 125 steps (converted for 1-2 phase excitation)Fully Closed: 0 step

Min: 0 Max: 125 Unit: step Reference Value

Cause of Out of RangeIdling after engine warmed up: 0 to 125 step(accordance with EGR control condition)

EGR valve1. Wire harness or connector2. ECM3.

327

Part 3


2 Data List

Cat-egory


Exh

aust

Cat

alys

t Mem

ory

Err

or


EEPROM error status for DPNR catalyst

When the DPF/DPNR catalyst thermal deterioration ●data exceeds the predetermined value, DTC P2002 is set and Error is displayed. ECM calculates and integrates the DPF/DPNR catalyst ●thermal deterioration data by the engine load.

Status No error / Error Unit: N/A Reference Value


No error: DPF/DPNR catalytic converter normal(DPF/DPNR catalytic converter thermal deterioration data does not exceed threshold)

DPF/DPNR catalytic converter is deterio-1. ratedAfter the DPF/DPNR catalyst has been 2. replaced, DPF/DPNR catalytic converter thermal deterioration data is not initial-ized.

Diff

. Pre

ss. S

enso

r Cor

r.


Differential pressure sensor 0 point learning value.Compensates the sensor output drift when the ignition switch is ON (the engine is stopped).

This number indicates the correction value (0 point ●calibrat ion) for compensation of var iance in the differential pressure sensor.If this value of DPF Differential Pressure does not ●approach 0 kPa when the ignition switch is ON (engine is stopped) and the Diff. Press. Sensor Corr. displays less than -1.5 kPa or more than 1.5 kPa, there may be a malfunction in the differential pressure sensor.Note however, that the output of the differential pressure ●sensor fluctuates depending on the temperature.

Min: -10 Max: 245.9 Unit: kPa Reference Value

Cause of Out of RangeIgnition switch ON (engine stopped): -1.5 to 1.5 kPaDifferential pressure sensor1.

ECM2.

DP

F Th

erm

al D

eter

iora

te


Displays the deterioration condition status from the DPF/DPNR catalyst thermal dete-rioration data

When the DPF/DPNR catalyst thermal deterioration ●data exceeds the predetermined value, DTC P2002 is set and Error is displayed.ECM calculates and integrates the DPF/DPNR catalyst ●thermal deterioration data by the engine load.

Status Normal / Deteriorated Unit: N/A Reference Value


Normal: DPF/DPNR catalytic converter normal(DPF/DPNR catalytic converter thermal deterioration data does not exceed threshold)

DPF/DPNR catalytic converter is deterio-1. ratedAfter the DPF/DPNR catalyst has been 2. replaced, DPF/DPNR catalytic converter thermal deterioration data is not initial-ized.Exhaust gas temperature sensor (In)3. Exhaust gas temperature sensor (Out)4.

DP

F D

iffer

entia

l Pre

ssur

e


Differential pressure sensor output value

When PM (Particulate Matter) builds up in the DPF/ ●DPNR catalyst, the “DPF Differential Pressure” value increases.If the differential pressure in front of and behind the ●catalyst becomes near the value of the “intake air amount multiplied by about 0.4”, the catalyst is probably clogged with PM even if DTC P2002 is not present.

Min: -5 Max: 100 Unit: kpa Reference Value


Idling: -3kPa to 3kPaDPF/DPNR catalytic converter1. Vacuum transmitting pipe clogged2. Dif ferential pressure sensor vacuum 3. hose clogged

328

Part 3


2 Data List

Cat-egory


Exh

aust

DP

F N

o A

ctiv

ate


Result of checking whether the catalyst is activated when the catalyst regeneration control is performed.

Exhaust gas temperature does not rise enough during ●the DPF/DPNR catalyst regeneration.If the exhaust gas temperature does not rise enough, ●then “No Activate” appears on the intelligent tester display. In this case, DPF/DPNR catalytic converter deterioration or clogging of the exhaust fuel addition injector are possible causes of the malfunction.Other possible causes include EGR valve malfunction, ●exhaust temperature sensor malfunction, and injector malfunction.

Status Activated / Not Activated Unit: N/A Reference Value


Activated: Catalyst regeneration control is performed.

DPF/DPNR catalytic converter1. Exhaust fuel addition injector2. Exhaust gas temperature sensor (In)3. Exhaust gas temperature sensor (Out)4. Fuel injector assembly5. ECM6.

DP

F P

M B

lock


DPF/DPNR catalyst differential pressure er-ror status The error is detected if the differential pres-sure is excessive due to catalytic converter PM deposit or if the differential pressure is too small due to fusion

If PM (Particulate Matter) builds up in the DPF/DPNR ●catalyst, the pressure differential from front to rear of the DPF/DPNR catalyst gradually increases.For example, at 3000 rpm (no load), i f the DPF ●Differential Pressure increases to MAF (mass air flow meter) x 0.4 kPa or more, “Blocked” appears on the intelligent tester display.In this case, clogging of the DPF/DPNR catalytic ●converter or exhaust fuel addition injector are possible causes of the malfunction.Other possib le causes inc lude in jec tor system ●malfunction, dif ferential pressure sensor system malfunction, exhaust leaks, and MAF meter malfunction.Clogging of the DPF/DPNR catalytic converter may ●be caused by the use of an oil that does not meet the specifications, such as a high-ash engine oil, or a high rate of engine oil consumption.

Status Not blocked / Blocked Unit: N/A Reference Value


Not blocked: DPF/DPNR catalytic converter normal

DPF/DPNR catalytic converter clogged1. Exhaust fuel addition injector2. Differential pressure sensor3. Vacuum transmitting pipe clogged4. Dif ferential pressure sensor vacuum 5. hose cloggedFuel injector assembly6. Exhaust gas leak7. MAF sensor8.

Add

. IN

J Fl

ow In

suffi

cien

t


Exhaust fuel addition injector error status:Exhaust fuel addition amount judged (Flow amount decrease) from the exhaust fuel ad-dition injector flow amount compensation value (Exhaust Fuel Addition FB)

One of the detection items for DTC P1386 (Exhaust fuel addition injector trouble detection diagnosis)(Not applicable on certain engines)

Status Normal / Error Unit: N/A Reference Value


Normal

Exhaust fuel addition injector1. DPF/DPNR catalytic converter2. Wire harness or connector3. Exhaust gas temperature sensor4. Engine components (air intake system, 5. exhaust system, fuel system, etc.)ECM6.

329

Part 3


2 Data List

Cat-egory


Exh

aust

Add

. IN

J Fl

ow E

xces

sive


Exhaust fuel addition injector error status:Exhaust fuel addition amount judged (flow amount excessive) from the air-fuel ratio sensor output value in the after-treatment control (catalyst regeneration control).




Normal

Exhaust fuel addition injector1. DPF/DPNR catalytic converter2. Wire harness or connector3. Air-fuel ratio sensor4. Engine components (air intake system, 5. exhaust system, fuel system, etc.)ECM6.

DP

F O

verte

mpe

ratu

re


Exhaust fuel addition injector error status:Exhaust fuel addition amount judged (high exhaust temperature 1000˚C or higher) from the air-fuel ratio sensor output value in the after-treatment control (catalyst regeneration control).




Normal

Exhaust fuel addition injector1. DPF/DPNR catalytic converter2. Wire harness or connector3. Exhaust gas temperature sensor4. Engine components (air intake system, 5. exhaust system, fuel system, etc.)ECM6.

Ric

h S

pike

Mal


Exhaust fuel addition injector error status:Exhaust fuel addition amount judged from the air-fuel ratio sensor output fluctuation during the after control (catalyst regenera-tion control)

DPNR catalytic converter installed vehicle ●One of the DTC P1386 (Exhaust fuel addition injector ●error detection diagnosis) detection items

(Not applicable on certain engine models)The error is detected when the air-fuel ratio fluctuation ●during the catalyst regeneration control when the exhaust fuel addition is performed is smaller or larger than the fluctuation value estimated by the ECM



Normal

Exhaust fuel addition injector1. DPF/DPNR catalytic converter2. Wire harness or connector3. Air-fuel ratio sensor4. Engine components (air intake system, 5. exhaust system, fuel system, etc.)ECM6.

330

Part 3


2 Data List

Cat-egory


Exh

aust

Cat

alys

t Diff

eren

tial P

ress


Catalyst differential pressure characteristic value

It shows that the catalytic converter is more clogged as ●the value gets largerValue calculated from the differential pressure sensor ●output value and the intake air amount (MAF)Displays almost the same value in the same filter ●clog condition even when the exhaust temperature changes during driving because the compensation by exhaust temperature is also performed. (If no exhaust compensation is performed, differential pressure rises as the temperature increases)I f the value exceeds 0.4, DTC P2002 (catalyst ●deterioration) may be set.

Min: -3.99 Max: 3.99 Unit: N/A Reference Value


Less than 0.2

Exhaust fuel addition injector1. DPF/DPNR catalytic converter2. Wire harness or connector3. Air-fuel ratio sensor4. Exhaust temperature sensor5. Engine components (air intake system, 6. exhaust system, fuel system, etc.)ECM7.

DP

NR

/DP

F S

tatu

s R

eju

(PM

)


Catalyst regeneration control (PM combus-tion) status For active test

These values do not change when automatic PM- ●release is occurring on the road.These can only be changed by applying forced ●regeneration with Active Test.

Standby: Displayed during normal operationReady: ECM tries to increase DPNR temp.Operate: Forced PM-release happenCompl.: Forced PM-released completedUsed for checking whether the after-treatment system is completely fixed after fixing.

Status Standby / Ready / Operate / Compl. Unit: N/A Reference Value

Cause of Out of Range Compl: Catalyst regeneration control (forcibly driven by Active Test) normally completed -

DP

NR

Sta

tus

Rej

u (S

)


Catalyst regeneration (desulfurization) sta-tusFor active test

These values are not changing during automatic ●S-release is occurring on the road.These can only be changed by applying forced ●regeneration with Active Test.

Standby: Displayed during normal operationReady: ECU tries to increase DPNR temp.Operate: Forced S-release happenCompl.: Forced S-released completed

Status Standby / Ready / Operate / Compl. Unit: N/A Reference Value

Cause of Out of Range Compl: Catalyst regeneration (forcibly driven by Active Test) control normally completed -

331

Part 3


2 Data List

Cat-egory


Exh

aust

Exh

aust

Fue

l Add

ition

FB


Exhaust fuel addition correction learning co-efficient

Exhaust Fuel Addition FB is a correction value to ●increase the fuel volume injected from the exhaust fuel addition injector when the catalyst temperature does not rise to the target range during DPF/DPNR catalyst regeneration.When the value exceeds 1.4, i t may be caused ●by following problems: f low amount decrease due to clogged addition injector, exhaust temperature decrease due to engine (injector, EGR etc.) problem or temperature rise problem due to catalyst converter deterioration. If the value is 1.0, there have been no increase or ●decrease of fuel addition amount by compensation.

Min: 0.8 Max: 1.99 Unit: N/A Reference Value


0.9 to 1.4

Exhaust fuel addition injector clogged1. DPF/DPNR catalyst deteriorated2. Engine assembly (intake system, exhaust 3. system, fuel system, EGR system, MAF, MAP sensor, etc.)ECM4.

Exh

aust

Tem

pera

ture

B#S

#


Exhaust gas temperatureB#S# represents the sensor location.

If an open occurs in an exhaust temperature sensor ●circuit, 1000°C is displayed on the intelligent tester.If a short occurs in an exhaust temperature sensor ●circuit, 0°C is displayed on the intelligent tester.Note that when a failure occurs, the default value (200°C) ●is displayed.

Min: 0 Max: 1000 Unit: °C Reference Value


150 to 300°C: Idling after engine warmed up500 to 700°C: During DPF/DPNR catalyst regeneration(AD series engine reference value)

Exhaust gas temperature sensor1. Exhaust fuel addition injector2. DPF/DPNR catalyst deteriorated3. Wire harness or connector4. ECM5.

EX

H G

AS

CTL

VS

V


Exhaust gas control VSV operation statusActive test support dataON: Active test “Exhaust Gas Control VSV” operating OFF: Normally operating after the engine warmed-up



OFF: Idling after engine warmed upExhaust gas control VSV1. Wire harness or connector2. ECM3.

332

Part 3


2 Data List

Cat-egory


Fuel

Com

mon

Rai

l Pre

s S

ens

2


Fuel pressure calculated from the 2nd fuel pressure sensor system. Only when there are 2 fuel pressure sensor systems

No large difference from the fuel pressure value

Min: 0 Max: 200000 Unit: kPa Reference Value


(AD series engine reference value)27 to 45 MPa when idling57 to 91 MPa when maintained at 3000 rpm with no load

Fuel pressure sensor1. Wire harness or connector2. Lack of fuel 3. Fuel injector4. Supply pump5. Pressure limiter / pressure discharge 6. valveFuel line (fuel pipes, fuel filter, air trapped 7. in fuel line, etc.)ECM8.

Fuel

Pre

ss


Common-rail actual fuel pressure

Inspect by comparing the fuel pressure with the Target ●Fuel Pressure and Common-rail Press Sens 2. When in a stable condition such as when idling, the fuel ●pressure is within +/-5 MPa of the target fuel pressure. The ECM uses fuel pressure for feedback control of the ●target fuel pressure via the supply pump. The injection amount is determined based on the injection timing and fuel pressure. Also, the spray pattern (multiple fuel injection) is selected based on the fuel pressure. When the fuel pressure is below 25 MPa during idling, it ●may cause rough idling. When the fuel pressure has decreased by 20 MPa from ●the target fuel pressure, there may be a lack of power. If actual fuel pressure is 40 MPa higher than the target ●fuel pressure, DTC P1229 will be stored. When it is lower than the target fuel pressure, “Lack of Power” will occur, but a DTC will not be stored. When the fuel pressure is higher than 200 MPa, DTC ●P0088 will be stored.



(AD series engine reference value)27 to 45 MPa when idling57 to 91 MPa when maintained at 3000 rpm with no load

Fuel pressure sensor1. Wire harness or connector2. Lack of fuel 3. Fuel injector4. Supply pump5. Pressure limiter / pressure discharge 6. valveFuel line (fuel pipes, fuel filter, air trapped 7. in fuel line, etc.)ECM8.

Targ

et C

omm

on-r

ail P

ress

ure Measurement Item Hint

Target common-rail pressure calculated by ECM

Inspect the (actual) fuel pressure, comparing it against ●the common-rail target value.Considered normal when the actual fuel pressure is ●within +/-5 MPa of the target fuel pressure under stable conditions.


Cause of Out of Range (AD series engine reference value)27 to 45 MPa when idling57 to 91 MPa when maintained at 3000 rpm with no load

ECM (Calculation items related to the fuel pressure control)

333

Part 3


2 Data List

Cat-egory


Fuel

Fuel

Tem

pera

ture


Fuel temperature from fuel temperature sen-sor signal

After a cold soak, the fuel temperature is the same as the outside air temperature.

Min: -40 Max: 140 Unit: °C Reference Value

Cause of Out of RangeChanges in accordance with the fuel temperature around the fuel temperature sensor (supply pump)

Fuel temperature sensor1. Wire harness or connector2. ECM3.

Inta

nk F

uel P

ump


Intank fuel pump operation status Operates according to fuel consumption amount(Operates after about 10 minutes of driving)


Cause of Out of RangeON: Intank fuel pump is operating.Only for vehicles equipped with a double tank.ECM (Calculation items related to the fuel

pump control)

Targ

et P

ump

SC

V C

urre

nt


Suppy pump target SCV energization cur-rent control

ECM-calculated value for the suction control valve ●actuation target current.Value is large when a high fuel pressure is desired. ●Value is more than 3000 mA when SCV does not move ●smoothly (poor movement due to deposits, etc.).When this deviates from the standard value, it indicates ●that for some reason, even though the pump is running hard, the actual fuel pressure is inconsistent with the target fuel pressure.

Min: 0 Max: 8191.875 Unit: mA Reference Value


800 to 3000 mAVaries in accordance with the rotation speed and injection volume.

Clogged fuel filter1. Supply pump (suction control valve mal-2. function)Wire harness or connector3. Fuel leaks in fuel line4. Clogging in fuel line5. Air trapped in fuel line (insufficient air 6. bleeding)

Fuel

Rou

te S

witc

hing

Val

ve Measurement Item Hint

Intank fuel pump fuel transfer mode and priming mode switching valve operation sta-tus

Fuel route switching relay operation status for fuel ●transferFuel routes for the fuel transfer mode and priming mode ●is switched arbitrarily by a user.


Cause of Out of RangeON: Priming mode selectedECM (Calculation items related to the fuel

pump control)

334

Part 3


2 Data List

Cat-egory


Mon

itor

Com

plet

e P

arts

Mon

itor Measurement Item Hint

Displays the support status of the system composition parts, that is currently being monitored by the on-board diagnosis, in ac-cordance with each country’s regulations.

NOT AVL: Without supportAVAIL: With support

Status NOT AVL / AVAIL Unit: N/A Reference Value

Cause of Out of RangeAVAIL

-

Fuel

Sys

tem

Mon


Displays the support status of the fuel sys-tem, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.



Cause of Out of Range NOT AVLThis item does not apply to diesel engines.-

Mis

fire

Mon

itor


Displays the support status of the misfiring detection, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.

NOT VAL: Without supportAVAIL: With support



Mis

fire

Mon

itor


Displays the support status of the misfiring detection, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.




EGR

/VV

T M

onito

r


Displays the support status of the EGR system, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.



Cause of Out of RangeAVAIL: Euro-OBD installed vehicle

-

EGR

/VV

T M

onito

r


Displays the diagnostic history status of the EGR system.

COMPL: Monitoring complete or not applicableINCMPL: Readiness code is used for monitoring incom-plete simulation test and for checking that the system is completely fixed after fixing

Status COMPL / INCMPL Unit: N/A Reference Value

Cause of Out of Range COMPL: Supported EGR system monitoring is all com-plete-

335

Part 3


2 Data List

Cat-egory


Mon

itor

O2S

(A/F

S) H

eate

r Mon


Displays the support status of the air-fuel ratio heater control system, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regula-tions.




O2S

(A/F

S) H

eate

r M

onito

r


Displays the diagnostic history status of the air-fuel ratio sensor.

COMPL: Monitoring complete or not applicableINCMPL: Monitoring incomplete


Cause of Out of Range COMPL: When not supported, COMPL is displayed per-manently. -

O2S

(A/F

S) M

onito

r


Displays the support status of the air-fuel ra-tio sensor, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.




O2S

(A/F

S) M

onito

r Measurement Item Hint

Displays the diagnostic history status of the air-fuel ratio sensor.




A/C

Mon

itor


Displays the support status of the air condi-tioner system, that is currently being moni-tored by the on-board diagnosis, in accor-dance with each country’s regulations.

NOT AVL: Not supportedAVAIL: Supported



A/C

Mon

itor


Displays the diagnostic history status of the air conditioner system.




2nd

Air

Mon

itor


Displays the support status of the secondary air injection system, that is currently being monitored by the on-board diagnosis, in ac-cordance with each country’s regulations.




336

Part 3


2 Data List

Cat-egory


Mon

itor

2nd

Air

Mon


Displays the diagnostic history status of the secondary air injection system.




EVA

P M

onito

r


Displays the support status of the EVAP system, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.




EVA

P M

onito

r


Displays the diagnostic history status of the EVAP system.




Hea

ted

Cat

alys

t Mon


Displays the support status of the heater catalyst system, that is currently being moni-tored by the on-board diagnosis, in accor-dance with each country’s regulations.




Hea

ted

Cat

alys

t M

onito

r


Displays the diagnostic history status of the heater catalyst system.




Cat

alys

t Mon

itor


Displays the support status of the catalytic converter, that is currently being monitored by the on-board diagnosis, in accordance with each country’s regulations.




Cat

alys

t Mon


Displays the diagnostic history status of the catalytic converter.




337

Part 3


2 Data List

Cat-egory


Oth

er S

yste

m

ACM

Inhi

bit


VSV for ACM (active control engine mount) status

Active Test item “Control the ACM Inhibit” support dataON: VSV for ACM ONOFF: VSV for ACM OFF


Cause of Out of Range VSV status:Engine switch is on (IG): OFF. ●Idling: ON. ●

ECM (Calculation items related to the active control engine mount system)

ACT

VS

V


Air conditioner cut control statusActive Test item “Control the A/C Cut Signal” support dataON: Air conditioner cut ONOFF: Air conditioner cut OFF


Cause of Out of RangeON: During cranking or acceleratingOFF: IdlingECM (Calculation items related to the air

conditioner control system)

Sw

irl C

ontro

l Val

ve V

SV Measurement Item Hint

VSV for No. 1 Swirl control valve status

Active Test item “Activate the VSV for Swirl Control Valve” support dataON: VSV for swirl control valve ONOFF: VSV for swirl control valve OFF


Cause of Out of RangeON: VSV ON (swirl control valve close)OFF: VSV OFF (swirl control valve open)ECM (Calculation items related to the swirl

control system)

Afte

r Glo

w


After glow operation

Whether the glow plug operation is affected or not can ●be determined by monitoring the glow plug energization command value when a problem occurs during engine start-up.When the battery voltage resistance value remains the ●same even if the glow command is changed (ON to OFF, or OFF to ON), it is believed that there may be a malfunction in the glow plug or circuit.

(TIPS: Whether the problem causes are related to the glow system or not can be determined only when all cyl-inders don’t operate such as in a case of relay operation problem.)



Flag is constantly on when the after glow is requested. Glow plug1. Glow relay2. Wire harness or connector3. ECM4.

338

Part 3


2 Data List

Cat-egory


Oth

er S

yste

m

Pre

Glo

w


Pre glow operation

Whether the glow plug operation is affected or not can ●be determined by monitoring the glow plug energization command value when a problem occurs during engine start-up.When the battery voltage resistance value remains the ●same even if the glow command is changed (ON to OFF, or OFF to ON), it is believed that there may be a malfunction in the glow plug or circuit.

(TIPS: Whether the problem causes are related to the glow system or not can be determined only when all cyl-inders don’t operate such as in a case of relay operation problem.)



Flag is constantly on when the pre glow is requested. Glow plug1. Glow relay2. Wire harness or connector3. ECM4.

Ele

ctric

Fan

Mot

or


Radiator cooling fan motor operation status

Active Test item “Control the Electric Cooling Fan” support dataON: Radiator fan motor ONOFF: Radiator fan motor OFF


Cause of Out of RangeON: Radiator fan motor activatedECM (Calculation items related to the radia-

tor fan control)

339

Part 3


2 Data List

Cat-egory


Sen

sor /

Sta

tus

Alte

rnat

e D

uty

Rat

io


Duty value generated by the alternator (Field duty value):Displays the generation status of the alter-nator (when an electrical load is applied to the alternator).

Outputs the alternator generation duty in order to see ●the electrical load.Can be used to determine whether a higher-than-normal ●injection volume at idle, etc. is resulting from electrical loading or from some other source. For example, when the duty is not high but the idling injection volume is high, there is injector volume degradation or high engine friction.Can be used for judging whether or not a malfunctioning ●component in the electr ical system is generating continual generation requests (ex. battery deterioration is causing an unending full recharge request, etc.). If the alternator duty is always MAX regardless of whether or not auxiliary devices such as A/C or heater is activated, there may be an abnormality in the electrical system, such as battery deterioration.



No electrical load at idling: 10 to 60% ●High electrical load at idling: 100% ●

Battery deterioration1. Alternator malfunction2.

Check for accessory lights, malfunctions, etc.

Atm

osph

ere

Pre

ssur

e


Actual atmospheric pressure

With the ignition switch ON, when the dif ference ●between the atmospheric pressure sensor and intake manifold absolute pressure is 8 kPa or higher, there is a malfunction in one of the sensors.With the ignition switch ON, when the atmospheric ●pressure is 0 kPa or 140 kPa, there is a malfunction in the sensor circuit.

Min: 0 Max: 255 Unit: kpa Reference Value

Cause of Out of RangeStandard atmospheric pressure: 101 kPa.For every 100 m increase in altitude, pressure drops by 1 kPa. Varies by weather.

Atmospheric pressure sensor itself has failed(atmospheric pressure sensor is inside the ECM)

Bat

tery

Vol

tage


Battery voltage If 11 V or less, characteristics of some electrical compo-nents change.

Min: 0 Max: 65.535 Unit: V Reference Value


11 to 14 VBattery deterioration1. Alternator malfunction2. Wire harness or connector3. ECM4.

Cal

cula

te L

oad


Calculated load by ECM (Load value calculated by ECM)

Current torque (Estimated)/Maximum output torque ●at current engine speed, or (Final injection volume/Maximum injection volume at current engine speed) x 100.Malfunction in which turbo pressure or Mass Air Flow ●(MAF) decreases


Cause of Out of Range 1VD-FTV reference valueIdling: 15.4 to 20.4% ●Running without load (2500 rpm): 20.1 to 25.9% ●Driving with the accelerator fully depressed at 3000 ●rpm: 80.3 to 99.6%Driving with the accelerator fully depressed at 4000 ●rpm: 96.4 to 98%

Mass air flow meter1. Manifold absolute pressure sensor2. ECM (Calculation items related to the fuel 3. injection volume control)

340

Part 3


2 Data List

Cat-egory


Sen

sor /

Sta

tus

Coo

lant

Tem

p


Engine coolant temperature

If the value is -40°C (-40°F) or 140°C (284°F), the ●sensor circuit is open or shorted.After a long soak, the coolant temperature, intake ●air temperature, and ambient air temperature will be approximately equal.

Min: -40 Max: 140 Unit: ˚C Reference Value


After warming up engine:75 to 90°C (167 to 194°F)

Engine coolant temperature sensor1. Wire harness or connector2. Thermostat3. ECM4.

Eng

ine

Run

Tim

e Measurement Item Hint

Time since the ignition switch was turned ON Time passed since the ignition switch was turned ON

Min: 0 Max: 65535 Unit: s Reference Value

Cause of Out of Range Displays the calculated value in accordance with the elapsed time. ECM (Timer built into the ECM)5.

Eng

ine

Spe

ed


Engine speed (crankshaft rotation speed)When the crankshaft position sensor is malfunctioning, “Engine speed” is approximately 0 or varies greatly from the actual engine speed.

Min: 0 Max: 6000 Unit: rpm Reference Value

Cause of Out of Range50 to 400 rpm: Cranking500 to 900 rpm: Idling with warm engine

Crankshaft position sensor1. Wire harness or connector2. ECM3.

Initi

al E

ngin

e C

oola

nt

Tem

p


Engine coolant temperature when engine started

For Freeze Frame Data, this tells whether the malfunction happened at a cold start or with a warm engine.


Cause of Out of RangeVaries in accordance with the engine coolant temperature at start.

Engine coolant temperature sensor1. Wire harness or connector2. ECM3.

Initi

al In

take

Air

Tem

p


Intake air temperature when engine startedFreeze frame date can be used to determine whether a malfunction occurs due to low atmospheric pressure or not.



Varies in accordance with the intake air temperature at engine start.

Intake air temperature sensor (around air 1. inlet port)Wire harness or connector2. ECM3.

Inta

ke A

ir


Intake air temperature (around air inlet port)

After a long soak, the engine coolant temperature, ●intake air temperature, and ambient air temperature will be approximately equal.If the value is -40°C (-40°F) or 140°C (284°F), the ●sensor circuit is open or shorted.



Displays a temperature which is nearly equal to the atmo-spheric temperature around the sensor.

Intake air temperature sensor (around air 1. inlet port or mas air flow meter)Wire harness or connector2. ECM3.

341

Part 3


2 Data List

Cat-egory


Sen

sor /

Sta

tus

Inta

ke A

ir Te

mp

(Tur

bo)


Intake air temperature (behind the turbo-charger)

Intake air temperature at the intake manifold (after ●intercooler).During fail-safe operation, the value is set to 165°C ●(329°F). As the value is set to a high temperature, the turbo pressure may be suppressed and there may be a lack of power.



Displays a temperature which is nearly equal to the atmo-spheric temperature around the sensor.

Intake air temperature sensor (behind the 1. turbocharger)Wire harness or connector2. ECM3.

MA

F


Intake air amount from the mass air flow me-ter

Based on the MAF, the ECM controls the fuel injection ●volume, injection timing, EGR, etc.If the value is always approximately 0 g/sec.: ●

- Mass air flow meter power source circuit is open.- VG circuit is open or shorted.

If the value is always 200 g/sec. or more: ●- EVG circuit is open.

Min: 0 Max: 200 Unit: g/sec Reference Value


Value differs according to EGR control2AD engine reference value:

Idling: 2.8 to 5.2 gm/s ●Running without load (2,500 rpm): 27.5 to 32.5 gm/s ●

1VD engine reference value: Idling: 5 to 12 g/sec. ●Running without load (2000 rpm): 28.2 to 130 g/sec. ●

Mass air flow meter1. Intake related clog or leak2. Exhaust related clog3. Turbocharger subassembly4. Leak or clog in passages for turbocharg-5. erMalfunction in which EGR valve does not 6. closeWire harness or connector7. ECM8.

MA

P


Intake manifold pressure

When the engine switch is on (IG) or the vehicle is ●idling, the intake manifold absolute pressure and atmospheric pressure are approximately the same (standard atmospheric pressure = 101 kPa).

Above approximately 1500 rpm, the turbo becomes effec-tive, and the pressure increases above atmospheric pres-sure.

Inspect while comparing with “Target Booster Pressure”. ●With the accelerator fully open, if the actual manifold ●absolute pressure (MAP) is low compared to the target booster pressure by at least 20 kPa for 5 seconds or more, a feeling of insufficient power will occur.

Min: 0 Max: 255 Unit: kpa Reference Value


Idling: 90 to 102 kPa (depending on atmosphere ●pressure)Engine running at 3000 rpm: 100 to 150 kPa ●

Manifold absolute pressure sensor1. Intake related clog or leak2. Exhaust related clog3. Turbocharger subassembly4. Leak or clog in passages for turbocharg-5. erEGR valve stuck open6. Exhaust leak7. Throttle valve stuck closed8. Wire harness or connector9. ECM10.

342

Part 3


2 Data List

Cat-egory


Sen

sor /

Sta

tus

Vehi

cle

Spe

ed


Actual vehicle speed Receives vehicle speed signals from the speedometer.

Min: 0 Max: 255 Unit: km/h Reference Value


Displays a value which is nearly equal to the actual ve-hicle speed.

Speed sensor circuit (speedometer cir-1. cuit)Speed sensor (wheel speed sensor)2. ECM3.

Am

bien

t Tem

pera

ture


Outside temperature

Receives outs ide temperature s ignals f rom air ●conditioner ECU.If the value is -40°C (-40°F) or 140°C (284°F) or more, ●the sensor circuit is open or shorted.Displays the intake air temperature around the air inlet ●port or behind the turbocharger, on CD engines or some conventional KD engines.

Refer to “Intake Air” or “Intake Air Temp (Turbo)”.


Cause of Out of RangeDisplays a value which is nearly equal to the outside air temperature.Malfunction in A/C system1.

ECM2.

343

Part 3


2 Data List

Cat-egory


Sw

itch

A/C

Sig

nal


Air conditioner (A/C) operation signal output from A/C amplifier

ON: A/C operating ●OFF: A/C not operating ●



ON: A/C operatingA/C system (A/C amplifier, A/C switch)1. Wire harness or connector2. ECM3.

ACC

Rel

ay


Powersource for accessory cut-off status

This item is applied to the vehicle with the cranking ●holding function.The ECM cuts of f the cur rent that powers the ●accessories while the engine is cranking.



ON: engine is crankedEngine starting system (cranking holding 1. function)Wire harness or connector2. ECM3.

Clu

tch

Sw

itch


Clutch start switch signal statusClutch start switch status for engine starting ●Clutch star t switch is ON when the clutch pedal ●depressed



ON: Clutch pedal depressedClutch start switch1. Wire harness or connector2. ECM3.

Imm

obili

ser C

omm

unic

atio

n


Engine immobiliser system statusOFF: Communication malfunctioning, or engine immobil-iser system setON: Communication normal



ON: Normal engine operationUse of a non-registered key1. Key battery is fully depleted2. Engine immobiliser system3. Wire harness or connector4. ECM5.

Neu

tral P

ositi

on S

W S

igna

l Measurement Item Hint

Park/neutral position switch signal status(for engine starting)

Park/neutral position switch status for engine starting ●Par k /neu t ra l pos i t i on sw i tc h i s O N when the ●transmission gear position is in P or N (neutral).



ON: Transmission gear in P or N (neutral)Park/neutral position switch (clutch start 1. switch)Wire harness or connector2. ECM3.

344

Part 3


2 Data List

Cat-egory


Sw

itch

Pow

er S

teer

. Sig

. Rec

ord


Power steering switch status history

Power steering switch output history (after disconnecting and reconnecting the battery):ON: Power steering operated in the past.OFF: Power steering did not operate in the past.


Cause of Out of RangeON: When steering wheel first turned after ignition switch ON

Power steering switch1. Wire harness or connector2. ECM3.

Pow

er S

teer

ing

Sig

nal

Rec

ord


Power steering switch status

ON: Power steering operatedOFF: Power steering not operatedOFF malfunction (OFF during power steering operation): Engine speed decreases temporarily when power steering is operating



ON: Power steering operationPower steering switch1. Wire harness or connector2. ECM3.

Sta

rter C

ontro

l


Starter switch signal (STSW terminal input status)

ON: STSW terminal voltage is highOFF: STSW terminal voltage is low



ON: Cranking (during ignition switch or engine switch op-eration)

Engine starting system (entry and start 1. system)Wire harness or connector2. ECM3.

Sta

rter R

elay


Starter relay (STAR terminal output status)

This item is applied to the vehicle with the cranking ●holding function.The cranking folding function provides current to ●the starter when the ECM detects the engine switch start signal (STSW). When the ECM performs a firing judgment, the system cuts current to the starter. The ECM keeps energizing the starter relay by outputting the current from STAR terminal.



ON: CrankingEngine starting system (cranking holding 1. function)Wire harness or connector2. ECM3.

345

Part 3


2 Data List

Cat-egory


Sw

itch

Sta

rter S

igna

l


Starter relay drive signal (STA terminal input status)

ON: Starter is operating. ●OFF: Starter is not operating. ●OFF malfunction (ignition switch is in ST position but ●the “Starter Signal” is OFF and the starter is operating): Wire harness is open or shorted to groundON malfunction (engine switch (STA) is OFF but the ●signal is ON and the starter is not operating): Wire harness is shorted to +BOperation malfunction: Engine switch malfunction, ●starter relay malfunction, starter malfunction, battery or battery cable is defective, or wire harness is open or shorted



ON: CrankingStarter relay1. Ignition switch (entry and start system)2. Wire harness or connector3. ECM4.

Sto

p Li

ght S

witc

h


Stop light switch signal (STP terminal input status)

OFF malfunction: Wire harness (stop light switch to ●ECM, stop light switch to +B) open or shorted to groundON malfunction: Wire harness (stop light switch to ECM) ●shorted to +B



ON: Light is on (Brake pedal is depressed).OFF: Light is off (Brake pedal is released).

Stop light switch1. Stop light2. Wire harness or connector3. ECM4.

346

Part 3


2 Data List

Cat-egory


Sym

ptom

Dia

gnos

is

A/C

Dut

y Fe

edba

ck V

alue


Injection volume correction value by air con-ditioning load

Expected injection volume increase after the A/C turns from off to on. The relationship between the air conditioning load and en-gine stalling can be confirmed. When the air conditioning is turned off, the load actually applied to the air conditioning does not decrease due to a failure in the air conditioning system and an excessive load is applied to the engine, which may cause engine stalling.



1VD engine reference value0 to 4.1 mm ● 3/st (A/T)0 to 2.6 mm ● 3/st (M/T)

Air conditioner control system (including 1. mechanical malfunctions in the air condi-tioner)Wire harness or connector2. ECM3.

Ele

ctric

Dut

y Fe

edba

ck V

alue


Injection volume correction value by electri-cal load

Expected injection volume increase after the electrical load turns from off to on. The relationship between the alternator load and engine stalling can be confirmed. When the alternator DUTY decreases, the load actually applied to the alternator does not decrease due to a fail-ure in the alternator and an excessive load is applied to the engine, which may cause engine stalling.



1VD engine reference value0 to 2.5 mm3/st

Charging control system (including elec-1. trical malfunctions in the charging sys-tems)Wire harness or connector2. ECM3.

Eng

ine

Spe

ed (S

tarte

r Off)


Engine speed when starter offEngine speed immediately after starting the engine.Vehicle behavior data to refer to when a problem occurs during engine start-up.

Min: 0 Max: 6000 Unit: rpm Reference Value


Varies in accordance with the engine start status.

Crankshaft position sensor1. STA signal circuit2. Starting system components3. Engine components (that affect engine 4. start problems)ECM5.

Eng

ine

Sta

rt Ti

me


Engine start (cranking) timeTime necessary for the engine to start.Vehicle behavior data to refer to when a problem occurs during engine start-up.

Min: 0 Max: 60 Unit: ms Reference Value


Varies in accordance with the engine start status.

Crankshaft position sensor1. STA signal circuit2. Starting system components3. Engine components (that affect engine 4. start problems)ECM5.

347

Part 3


2 Data List

Cat-egory


Sym

ptom

Dia

gnos

is

PS

Dut

y Fe

edba

ck V

alue


Injection volume correction value by power steering load

Expected injection volume increase after the power steer-ing turns from off to on.The relationship between the power steering load and en-gine stalling can be confirmed. When the steering operation angle is held (at minimum load applied to the power steering), the load actually ap-plied to the power steering system does not decrease due to a failure in the system and an excessive load is applied to the engine, which may cause engine stalling.



1VD engine reference value0 mm3/st

Air conditioner control system (including 1. mechanical malfunctions in the air condi-tioner system)Wire harness or connector2. ECM3.

Run

Dis

t of P

revi

ous

Trip


Previous trip distance

Used to confirm the driving conditions of the previous ●trip (before the malfunction occurred).

On gasoline engines, if a short circuit occurs constantly, it may deteriorate the engine startability due to ignition plug smoking. On diesel engines, when the vehicle often travels under a light load such as in the case of a short trip or idling, the injector ports will be clogged, causing a shortage in the fuel injection volume, which may result in deterioration of startability and idle stability.

Min: 0 Max: 326.4 Unit: km Reference Value

Cause of Out of Range Varies in accordance with the vehicle driving conditions.

-

Sta

rter C

ount


The number of times that the starter turns on.

Number of times the starter turned on from the time the ignition switch was turned ON.

Min: 0 Max: 127 Unit: Times Reference Value

Cause of Out of Range Varies in accordance with the number of times that the starter turns on. -

348

Part 3


2 Data List

Cat-egory


Test

Av E

ngin

e S

peed

of A

ll C

yl


Crankshaft rotation speed (average of all cylinders)Active test support data

Output only when the Active Test “Check the Cylinder ●Compression” is performed. Indicates the average engine speed of all cylinders ●during cranking. Refe r to the Ac t i ve Tes t “Check the Cy l inder ●Compression”.

Min: 0 Max: 51199.21875 Unit: rpm Reference Value

Cause of Out of RangeVaries in accordance with the engine friction.Engine mechanical components (related to

the engine friction)

Eng

ine

Spe

ed o

f Cyl

#


Crankshaft rotation speed for each cylinderActive test support data# represents the cylinder number

Output only when the Active Test “Check the Cylinder ●Compression” is performed.Indicates the speed of each cylinder when cranking. ●

Example - Normal: Engine speed of all cylinders is approximately equal. When No. 1 cylinder compression is low, “Engine speed of Cyl #1” is approximately 300 rpm, and “Engine speed of Cyl #2 to #4” is approximately 200 rpm.

Refe r to the Ac t i ve Tes t “Check the Cy l inder ●Compression”.

Min: 0 Max: 51199.21875 Unit: rpm Reference Value

Cause of Out of Range“Engine speed” of all cylinders almost sameEngine mechanical components (related to

the engine friction)

349

Part 3


2 Data List

Cat-egory


VN

Tur

boch

arge

r

Boo

st P

ress

ure

Dev

iatio

n


Difference between target and actual super-charging pressure

“Target Booster Pressure” and “MAP” values calculated by the ECM.

Min: -320 Max: 320 Unit: kPa Reference Value


1VD engine reference value:Idling after engine warmed up and vehicle under normal atmospheric pressure: -3 to 10 kPa

Turbocharger1. Air intake system (leak or clog)2. Exhaust system (leak or clog)3. EGR system (EGR valve or passage 4. clog)Manifold absolute pressure sensor or 5. sensor hoseECM6.

Targ

et B

oost

er P

ress

ure


Target boost pressure (value calculated by the ECM)

Inspect while comparing with “MAP”. ●With the accelerator fully open, if the actual manifold ●absolute pressure (MAP) is low compared to the target booster pressure by at least 15 kPa for 5 sec. or more, a feeling of a lack of power will occur.


Cause of Out of RangeIdling after engine warmed up and vehicle is under normal atmospheric pressure: 89 to 100 kPaECM (Calculation items related to the turbo

pressure control)

VN

Tur

bo C

omm

and


Variable nozzle vane opening degree com-mand value (value calculated by the ECM)

“VN Turbo command” is a command value. ●0%: Full open vanes (contraction of actuation-use rods) ●90% or more: Ful ly c losed vanes (ex tension of ●actuation-use rods)When this value is large, the turbo works well. ●There is no actual opening angle data to handle the VN ●Turbo command value.


Cause of Out of Range20 to 100%ECM (Calculation items related to the turbo

pressure control)

VN

Tur

bo E

rror

Lev

el


VN turbo driver opening angle level when abnormality detected

3: Nearly fully closed (supercharging pressure and pre- ●turbine pressure are incredibly high and there is a risk of engine damage). 2: Roughly intermediate opening angle (not as bad as “3”, ●but long-term usage is problematic). 1: Nearly fully open (will not cause engine damage, but ●at a low RPM, turbocharging pressure will not rise and insufficient power will be felt). 0: Normal ●



0: Normal

Turbocharger1. Turbo motor driver2. Exhaust system (leak or clog)3. EGR system (EGR valve or passage 4. clog)Manifold absolute pressure sensor or 5. sensor hoseECM6.

350

Part 3


2 Data List

Cat-egory


VN

Tur

boch

arge

r

VN

Tur

bo M

ax A

ngle Measurement Item Hint

Maximum nozzle vane opening degreeVane maximum angle expressed in %As this value displays the ideal constant upper limit, no matter what happens, this value should not change.


Cause of Out of Range100%

-

VN

Tur

bo M

in A

ngle Measurement Item Hint

Minimum nozzle vane opening degreeVane maximum angle expressed in %As this value displays the ideal constant lower limit, no matter what happens, this value should not change.


Cause of Out of Range0 to 52 %

-

VN

Tur

bo O

pera

tion

Pro

hibi

t


Status that forced drive of the nozzle vane is prohibited.

OK: Status when the nozzle vane can be forcibly driven. NG: Status when the nozzle vane cannot be forcibly driv-en.

When NG, indicates a condition where the engine ●software does not allow the VN turbo Active Test.

Status OK / NG Unit: N/A Reference Value


OK: Active Test item “Test the Turbo Charger Step Motor” can be performed

When the execution conditions for the active test are not met. Ex.:

Ignition switch is OFF.1. Combustion control is in the modes other 2. than normal combustionActive Test request valve opening de-3. grees are other than the full open degree

VN

Tur

bo T

ype


Indicates the VN turbo vane actuation meth-od.

Not Avl: NoneCommo: Communication type with the turbo motor driver (DC motor)Vacuum: Vacuum actuator typeCAN Com: CAN communication type

Status Not Avl / Commo / Vacuum Unit: N/A Reference Value

Cause of Out of RangeDepends on the engine specifications

-

351

Part 3


2 Data List

Cat-egory


Vehi

cle

Spe

cific

atio

ns

Cyl

inde

r Num

ber Measurement Item Hint

Cylinder number Identifying cylinder number


Cause of Out of Range4 or 8

-

Des

tinat

ion


Destination

Identifying destination:A: North AmericaG: GermanyK: CanadaQ: AustraliaV: Middle EastW: Europe

Status ASCII code output Unit: N/A Reference Value

Cause of Out of RangeW: Europe

-

Eng

ine

Type


Engine type Identifying engine type


Cause of Out of Range Example:2ADFHV1VDFTV-

Mod

el C

ode


Vehicle model Identifying model code


Cause of Out of Range Example:ADT27#-

Mod

el Y

ear


Model year Identifying model year

Min: 1900 Max: 2155 Unit: MY Reference Value

Cause of Out of Range200#

-

Sys

tem

Iden

tifica

tion


System Identification

Identifying engine type:DieselGasolineHVCNG/LPG

Status Diesel / Gasoline Unit: N/A Reference Value

Cause of Out of RangeDiesel

-

Tran

smis

sion

Typ

e


Transmission (transaxle) type

Identifying transmission type:MTECT(4th)ECT(5th)ECT(6th)CVTMMT

Status MT / ECT Unit: N/A Reference Value

Cause of Out of Range MT: Manual transmission ●ECT 6th: Automatic transmission ●-

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3 Active Test6

Outline11

Actuator Driven by Active Test[1[ Active Test is a function to drive and test the actuator. ●

The actuator does not operate unless specified conditions are satisfied, but this function can force the ●

actuator to activate to check its operation.If the operation conditions of the actuator when activated in this way are normal, the drive circuits, ●

including the ECM, are judged to be normal without the need to conduct individual inspections or harness inspections.

Active Test Items[2[ Following systems can be driven and tested using the Active Test function. ●

Category DescriptionActive Control Engine Mount System Activating the VSV for the active control engine mount

Charging control Forcibly controlling the charging systemCylinder Compression Cylinder compression measurement

Diagnosis Connecting the TC and CG terminals of DLC3Diesel Throttle Driving the diesel throttle

EGR Driving the EGR system related componentsExhaust Forcibly recovering the DPF/DPNR catalyst

Fuel Driving the fuel system related componentsSwitch Driving the switches and relays

Swirl Control Driving the swirl control valveTurbocharger Driving the turbocharger related components

REFERENCE This manual describes the Active Test items by dividing them in the above categories to improve ●

searchability.However, Intelligent Tester cannot show the Active Test items in categorized groups. ●

Even on the types of engines that correspond with the active test items, the items may not be displayed on the tester depending on the vehicle model and model year.

NOTICE

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Details of Active Test Items21

Category Tester Display Indication Summary Diagnostic Notes

Act

ive

Con

trol

Eng

ine

Mou

nt

Sys

tem

Con

trol t

he A

CM

In

hibi

t

Test Detail Hint

VSV for ACM (active control engine mount) control

ON:VSV for ACM ONOFF:VSV for ACM OFF

Reference Monitor Item

ACM InhibitControl Range ON / OFF Unit: N/A

Cha

rgin

g co

ntro

l

Con

trol t

he V

olta

ge o

f A

ltern

ator

Test Detail Hint

Request output voltage of generator

This test checks the charging control Test possible while vehicle stopped and engine idling


Battery VoltageAlternate Duty RatioAlt Vol - Active TestAlt Vol - Non Active Test

Control Range 12.5 to 14.8 Unit: V

Cyl

inde

r C

ompr

essi

on

Che

ck th

e C

ylin

der

Com

pres

sion

Test Detail Hint

Check the cylinder compression pressure

Fuel injection stop in all cylindersTo perform the Active Test, see “Reference” below


Av Engine Speed of All CylEngine Speed of Cyl 1 to 4 (1 to 8)

Control Range ON / OFF Unit: N/A

Dia

gnos

is

Con

nect

the

TC

and

TE1

Test Detail Hint

Turn on TC and TE1 connectionWhen the Active Test is performed, the system behaves as if TC and CG were connected.


TC and TE1Control Range ON / OFF Unit: N/A

Die

sel T

hrot

tle

Die

sel T

hrot

tle T

arge

t Ang

le

#

Test Detail Hint

Control the diesel throttle valve# represents the bank

This test checks the diesel throttle valve ●Test possible when following conditions met: ●Ignition switch ON1. Engine is stopped2.


Actual Throttle Position #Throttle Motor DUTY #Throttle Sensor # Volt %Target Throttle Position #

Control Range 0 to 90 Unit: %

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EGR

Con

trol t

he E

GR

Sys

tem

Test Detail Hint

Activate E-VRV for EGR control

This test checks the EGR system driven by ●the vacuum actuatorE-VRV drive duty ratio of 45% or 65% is ●output


EGR VSVEGR Close Learn Val.EGR Lift Sensor Output #Target EGR Pos. #


Con

trol t

he E

GR

Ste

p P

ositi

on # Test Detail Hint

Control the EGR valve position# represents the bank

This test checks the EGR system driven by ●the linear solenoidTest possible when following conditions met: ●Ignition switch ON1. Engine is stopped2.


Actual EGR Valve Pos.#EGR Close Lrn. Val. #EGR Lift Sensor OutputEGR Operation ProhibitTarget EGR Pos #

Control Range

0 to 100(1 to 100) Unit: %

Act

ivat

e th

e V

SV

for

EGR

Cut

Test Detail Hint

Activate VSV (for EGR Cut)This test checks the EGR system driven by ●the vacuum actuator


EGR VSVEGR Close Learn Val.EGR Lift Sensor Output #Target EGR Pos. #


EGR

Ste

p

Test Detail Hint

Open and close EGR valve

This test checks the EGR system driven by ●the step motorEGR valve fully closed at step position 0, ●and fully open at step position 125Amount of EGR gas, f lowed into intake ●manifold, varies in accordance with EGR valve opening angle


EGR VSVEGR Close Lrn. Val.EGR Step POS

Control Range 0 to 125 Unit: step

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Exh

aust

Act

ivat

e th

e D

PF

Rej

uven

ate

(S)

Test Detail Hint

Perform DPNR catalyst regeneration (desulfu-rization)

This test checks the DPNR system, and is ●also used after repairRa ise c onver te r bed tempera tu re to ●more than 600°C (1,112°F) by adding fuel intermittently using the exhaust fuel addition injector and provide rich air-fuel ratio


Catalyst Memory ErrorDiff. Press. Sensor Corr.DPF Thermal DeteriorateDPF Differential PressureDPF No ActivateDPF PM BlockDPNR/DPF Status Reju (PM)DPNR Status Reju (S)Exhaust Fuel Addition FBExhaust Temperature B#S#AF Lambda B#S#AFS Voltage B#S#


Act

ivat

e th

e D

PF

Rej

uven

ate

(PM

)

Test Detail Hint

Perform DPF/DPNR catalyst regeneration (PM combustion)

This test checks the DPF/DPNR system, and ●is also used after repairRa ise c onver te r bed tempera tu re to ●more than 600°C (1,112°F) by adding fuel intermittently using the exhaust fuel addition injector


Catalyst Memory ErrorDiff. Press. Sensor Corr.DPF Thermal DeteriorateDPF Differential PressureDPF No ActivateDPF PM BlockDPNR/DPF Status Reju (PM)DPNR Status Reju (S)Exhaust Fuel Addition FBExhaust Temperature B#S#AF Lambda B#S#AFS Voltage B#S#


Exh

aust

Gas

C

ontro

l VS

V

Test Detail Hint

Activate the VSV for exhaust gas controlThis test checks the exhaust gas control sys-tem


EXH GAS CTL VSVControl Range ON / OFF Unit: N/A

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Fuel

Act

ivat

e th

e In

tank

Fue

l Pum

p R

elay

Test Detail Hint

Activate the FUEL PUMP (SUB PUMP) relay

This test checks the sub tank fuel pump ●operationTest possible when engine is stopped. ●This test activates the relay for only 60 ●seconds. After finishing this test, the vehicle does not ●permit activating the relay again within 60 seconds.


Intank Fuel PumpFuel Route Switching Valve


Test

the

Fuel

Lea

k

Test Detail Hint

Pressurizes common rail internal fuel pres-sure, and checks for fuel leaks

This test is used in the following operations: ●Checking for leaks in the high-pressure fuel 1. pipingChecking the component parts used in the 2. fuel pressure controlBleeding air after the high-pressure fuel 3. system is repaired

Fu e l p r e s s u r e i n s i d e c o m m o n r a i l ●pressurized to specified value and engine speed increased to 2,000 rpm when ON is selectedAbove conditions preserved while test is ON ●


Engine SpeedFuel PressTarget Common Rail PressureTarget Pump SCV CurrentMAPMAF

Control Range Stop / Start Unit: N/A

Con

trol t

he C

ylin

der #

Fue

l Cut

Test Detail Hint

Cut off fuel injection from each injector# represents the cylinder number

This test identif ies a defective cylinder ●(checks power balance)Fuel injection is stopped while the test is ON. ●Confirm that the vehicle is stopped and the ●engine is idling.If the running condition of the engine does ●not worsen even though injection of the designated cylinder is stopped, the cylinder can be confirmed to be malfunctioning.


Engine SpeedFuel PressTarget Common Rail PressureInjection Feedback Val Cyl#


Con

trol t

he A

ll C

ylin

ders

Fue

l Cut Test Detail Hint

All cylinder injector fuel cutThis test measures cylinder compression ●Test possible during vehicle stopping ●


Engine SpeedFuel PressTarget Common Rail Pressure


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Sw

itch

Con

trol t

he A

/C c

ut S

igna

l Test Detail Hint

Air conditioner operation prohibit

This test prohibit the air conditioner operation ●prohibitTest possible when following conditions met: ●Ignition switch ON1. Engine is stopped2.


A/C SignalControl Range ON / OFF Unit: N/A

Con

trol t

he E

lect

ric

Coo

ling

Fan

Test Detail Hint

Control the electric cooling fan operation

This test checks the cooling fan motor ●functionTest possible when following conditions met: ●Ignition switch on (IG)1. Engine is stopped2.


Electric Fan MotorControl Range ON / OFF Unit: N/A

Act

ivat

e th

e S

tarte

r Rel

ay

Test Detail Hint

Activate the starter relay

Test possible when engine stopped ●This item is applied to the vehicle with the ●cranking holding function.The cranking folding function provides ●current to the starter when the ECMdetects the engine switch star t signal (STSW). When the EC performs a firing judgment, the system cuts current to the starter. The ECM keeps energizing the starter relay by outputing the current from STAR terminal.


Starter RelayStarter ControlStarter SignalACC Relay


Act

ivat

e th

e AC

C C

ut R

elay

Test Detail Hint

Active the ACC relay (ACC CUT relay)

This item is applied to the vehicle with the ●cranking holding function.Test is possible when following conditions ●are met:Ignition switch ON1. Engine is stopped2.


Starter RelayStarter ControlStarter SignalACC Relay


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Sw

irl C

ontro

l

Act

ivat

e th

e V

SV

for S

wirl

C

ontro

l Val

ve

Test Detail Hint

Activate VSV for No. 1 Swirl Control Valve

This test checks the VSV for swirl control ●valveTest possible when following conditions met: ●Ignition switch ON1. Engine is stopped2.


Swirl Control Valve VSVControl Range ON / OFF Unit: N/A

Turb

ocha

rger

Test

the

Turb

o C

harg

er S

tep

Mot

or #

Test Detail Hint

Drive the turbocharger nozzle vanes

This test checks the turbocharger function ●Test possible when Data List item “VN Turbo ●Operation Prohibit” indicates “OK”.Test is impossible when any of the following ●conditions is metIgnition switch OFF1. Combustion control is in the modes other 2. than normal combustionActive Test request valve opening degrees 3. are other than the full open degree


MAPVN Turbo CommandTarget Booster PressureVN Turbo Operation Prohibit

Control Range

0 to 100(40 to 100) Unit: %

Act

ivat

e th

e V

SV

for T

urbo

P

ress

ure

Test Detail Hint

Drive the atmospheric pressure measurement switching VSV of the manifold absolute pres-sure sensor(Used to the engine that has the combination type atmospheric pressure sensor)

This test checks the VSV for turbo pressure ●sensorTest possible when following conditions met: ●Ignition switch ON1. Engine is stopped2.


MAPControl Range ON / OFF Unit: N/A

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REFERENCE Check the Cylinder Compression:When performing the Active Test item “Check the Cylinder Compression” and then cranking the engine, the ECM stops the fuel injection, and measures the engine speed for each cylinder.If one cylinder’s speed is higher than the others, that cylinder’s compression pressure can be concluded to be lower than the others.

Warm up the engine.1. Turn the ignition switch to OFF.2. Connect a Techstream to the DLC3.3. Turn the ignition switch to ON.4. Turn the tester ON.5. Select the following menu items: Powertrain / Engine and ECT / Active Test / Check the Cylinder 6. Compression.Select the following monitor items: Compression / Engine Speed of Cyl #1 to #4 (#8), Av Engine 7. Speed of All CylPress the RIGHT or LEFT button to change the Check the Cylinder Compression to ON.8. Fuel injection for all cylinders is prohibited at this time, and each cylinder’s engine speed measurement will enter standby mode.Crank the engine until the monitor item values “Engine speed of Cyl #1 to #4 (#8)” and “Av Engine 9. Speed of All Cyl” change.Monitor the engine speed (Engine Speed of Cyl #1 to #4 (#8), Av Engine Speed of All Cyl) 10. displayed on the tester.The tester displays the values to be extremely high before cranking the engine. Each cylinder’s engine speed is measured while cranking the engine and then the tester displays the actual engine speed values.

The Active Test item “Check the Cylinder Compression” will automatically turn off 255 seconds 1. after the Active Test is turned on.When the “Check the Cylinder Compression” is OFF and the engine is cranked, the engine will 2. start.If the “Check the Cylinder Compression” test needs to be performed again after each cylinder’s 3. engine speed measurement has been performed once, press EXIT to return to the Active Test menu screen. Then perform the Check the Cylinder Compression test again.Use a fully-charged battery.4.

NOTICE

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System Check Function “ Pressure Discharge Valve Check” (applicable to 31

some engines since September 2008)

Outline of Pressure Discharge Valve Check[1[ “Pressure Discharge Valve Check” in the System Check is used to diagnose the fuel pressure control ●

and improper combustion.Malfunctions can be determined by checking the fuel pressure when performing a fuel cut and ●

operating the pressure discharge valve with the intelligent tester.During “Pressure Discharge Valve Check”, the intelligent tester measures the fuel pressure while the ●

engine is running, after the engine is stopped, and after the pressure discharge valve operates.

Conducting Pressure Discharge Valve Check[2[ Enter the menu options in this order: Powertrain / Engine and ECT / Utility / Pressure Discharge Valve ●

Check.Unless all the following conditions are met, the Pressure Discharge Valve Check cannot be ●

performed.Vehicle is stopped. ●

Fuel pressure is less than 100000 kPa. ●

Fuel pressure sensor is normal. ●

Battery voltage is more than 8V. ●

There are two types of Pressure Discharge Valve Check as follows. Select either of them, and then ●

press Next.“Close to Open Check” opens the pressure discharge valve after the engine stops. ●

“Always Closed Check” holds the pressure discharge valve closed during the check. ●

Example:

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Diagnostic Hints[3[ During “Close to Open Check”, if there is no large change in the fuel pressure when the pressure ●

discharge valve is closed while the engine is running and after the engine is stopped, and if the value is 0 kPa when the pressure discharge valve is open, the system is normal.Perform “Always Closed Check” if the value is not 0 kPa when the pressure discharge valve is open ●

during “Close to Open Check”. If the results are the same as during “Close to Open Check”, there is a pressure discharge valve operation malfunction.If the fuel temperature is high, perform “Pressure Discharge Valve Check” after the fuel has cooled to ●

the outside air temperature.If a large amount of fuel is leaking, the fuel pressure decreases when the engine is stopped. However, ●

the condition of the pressure discharge valve can still be determined by comparing the measurement results of “Close to Open Check” and “Always Closed Check”.

Fuel Press recorded point

Fuel Press(When “Close to Open Check” selected)

Fuel Press(When “Always Closed Check” selected)

Engine Speed

Fuel cut operation signal

Pressure Discharge Valve operation start

Pressure Discharge Valve operation prohibit

Pressure Discharge Valve operation (Always Closed Check)

Pressure Discharge Valve operation (Close to Open Check)

0 kPa

0 kPa

0 rpm

ON

OFF

ON

OFF

OFF

Close (ON)

Open (ON)

Close (ON)

OFF

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