SECTION 2 Diagnostic Methods Contentsjuchems.com/ServiceManuals/viewfileb892.pdf · Output Test...

SECTION 2

Diagnostic Methods

Contents

Diagnostic Methods..........................................................................2-1

Overview.......................................................................................2-1

Diagnostic Tools...............................................................................2-2

Scan Tool Setup and Functionality..................................................2-3

Vehicle Check And Preparation.......................................................2-4

Visual Checks...............................................................................2-4

Vehicle Preparation ......................................................................2-4

Quick Test Description.....................................................................2-5

Clear the Continuous Diagnostic Trouble Codes (DTCs)and Reset the Emission Monitors Information in thePowertrain Control Module (PCM) ..............................................2-8

Resetting The Keep Alive Memory (KAM) ......................................2-9

On Board System Readiness (OSR) Test.....................................2-10

Output State Control (OSC)...........................................................2-11

One Touch Integrated Start System.......................................2-11

Output Test Mode (OTM)...............................................................2-12

Parameter Identification (PID)........................................................2-13

Freeze Frame Data........................................................................2-22

2011Powertrain Control/Emissions Diagnosis, 8/2010

SECTION 2

Diagnostic Methods

Contents (Continued)Flash Electrically Erasable Programmable Read Only

Memory (EEPROM)...................................................................2-24

Diagnostic Monitoring Test Results Mode 6..................................2-27

On Board Diagnostic (OBD) Drive Cycle ......................................2-28

Intermittent Diagnostic Techniques................................................2-34

Recreating the Fault ...................................................................2-34

Accumulating PCM Data ............................................................2-34

Peripheral Inputs ........................................................................2-35

Comparing PCM Data ................................................................2-35

Adaptive Fuel Diagnostic Trouble Code (DTC) DiagnosticTechniques ................................................................................2-36


Diagnostic Methods 2-1

Table of Contents

Diagnostic Methods

Overview

When following powertrain diagnostics on vehicles with on board diagnostic (OBD), the systemmay be checked by an off-board tester referred to as a scan tool. This section contains informationfor carrying out diagnostics with a scan tool. A scan tool has certain generic capabilities that arestandard across the automotive industry in the United States and Canada. All functions areselected from a menu. Refer to the instruction manual provided by the tool manufacturer.


2-2 Diagnostic Methods

Diagnostic Tools

Below is an equipment list with corresponding part numbers:

REQUIRED EQUIPMENT:

• Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software withappropriate hardware, or equivalent scan tool with functionality described under Scan Tool Setupand Functionality.

• Rotunda Smoke Machine, Fuel Evaporative Emission System Tester 218-00001 (522) orequivalent.

RECOMMENDED EQUIPMENT:

• Rotunda Vacuum/Pressure Tester 164-R0253 or equivalent. Range 0-101.3 kPa (0-30 in-Hg.)Resolution 3.4 kPa (1 in-Hg.)

• Fuel Pressure Test Kit 310-D009 (D95L-7211A) or equivalent.

• Fuel Pressure Test Adapter 310-180 or equivalent.

• Digital Multimeter (DMM) FLU77-4 or equivalent.

• Adjustable Ignition Spark Tester THX404 or equivalent.

• Non-powered test lamp.



Scan Tool Setup and Functionality

Connect the scan tool to the data link connector (DLC) for communication with the vehicle.

The DLC is located in the driver side compartment under the steering column. It is attached to theinstrument panel and accessible from the driver seat.

The DLC is rectangular in design and capable of accommodating up to 16 terminals. Theconnector has keying features to allow easy connection.

The required scan tool functions are described below:

— monitor, record, and playback of parameter identification (PID)

— freeze frame PID data

— diagnostic test modes; self-test, clear diagnostic trouble codes (DTCs)

— output state control

— output test mode

— resetting keep alive memory (KAM)

— diagnostic monitoring test results (mode 6) for on board diagnostic (OBD) monitors

— on board system readiness (OBD monitor completion status)

Some of these functions are described in this section. Refer to the scan tool manufacturer’sinstruction manual for specific information on scan tool setup and operation.

International Standards Organization (ISO) 14229 DTC Descriptions

The ISO 14229 DTC is a set of common requirements for diagnostic systems. The scan tooldisplays a failure type and a status type with the DTC. The types display additional information onthe scan tool for the condition that set the DTC. For a list of failure type descriptions, refer toSection 1, Powertrain Control Software, International Standards Organization (ISO) 14229Diagnostic Trouble Code (DTC) Descriptions.



Vehicle Check And Preparation

Before using the scan tool to carry out any test, refer to the important Safety Notice located at thebeginning of this manual and the necessary visual checks listed below.

Visual Checks

• Inspect the air cleaner and inlet duct.

• Check all engine vacuum hoses for damage, leaks, cracks, kinks, and proper routing.

• Check the electronic engine control (EEC) system wiring harness for proper connections, bent orbroken pins, corrosion, loose wires, and proper routing.

• Check the powertrain control module (PCM), sensors, and actuators for physical damage.

• Check the engine coolant for proper level and mixture.

• Check the transmission fluid level and quality.

• Make all necessary repairs before continuing with the quick test. Refer to Quick Test in thissection for additional information.

Vehicle Preparation

• Carry out all safety steps required to start and run vehicle tests. Apply the parking brake, placethe gear selector lever firmly into the PARK position on automatic transmission vehicles orNEUTRAL on manual transmission vehicles, and block the drive wheels.

• Turn off all electrical loads such as radios, lamps, A/C, blower, and fans.

• Start the engine (if the engine runs) and bring it up to the normal operating temperature beforerunning the quick test.



Quick Test Description

Quick Test

The quick test is divided into 3 specialized tests:

(1) Key On Engine Off (KOEO) On Demand Self-Test

(2) Key On Engine Running (KOER) On Demand Self-Test

(3) Continuous Memory Self-Test

The quick test checks the integrity and function of the electronic engine control (EEC) system andoutputs the test results when requested by the scan tool. The quick test also provides a quickcheck of the powertrain control system, and is usually carried out at the start of each diagnosticprocedure with all accessories off. The quick test is also carried out at the end of most pinpointtests for verification of the repair and to make sure no other concerns are incurred while repairinga previous concern. A system pass is displayed when no diagnostic trouble codes (DTCs) areoutput and a scan tool communication error does not exist. System pass means that hardwaremonitored by the powertrain control module (PCM) is functioning within the normal operating limits.Only a system pass, a DTC, or an incomplete on board diagnostic (OBD) drive cycle is displayed.

For applications that use a stand-alone transmission control module (TCM) the PCM does notoutput TCM DTCs. For TCM self-test and diagnostics, refer to the Workshop Manual Section307-01 Automatic Transmission.

Key On Engine Off (KOEO) On Demand Self-Test

The KOEO on demand self-test is a functional test of the PCM carried out on demand with the keyon and the engine off. This test carries out checks on certain sensor and actuator circuits. Aconcern must be present at the time of testing for the KOEO self-test to detect the concern. Whena concern is detected, a DTC is output on the data link at the end of the test as requested by thescan tool.

Key On Engine Running (KOER) On Demand Self-Test

The KOER on demand self-test is a functional test of the PCM carried out on demand with the keyon, the engine running and the vehicle stopped. A check of certain inputs and outputs is madeduring operating conditions and at a normal operating temperature. The brake pedal position,transmission control, and the power steering tests are part of the KOER on demand self-test andmust be carried out during this operation if applicable. These are described below. A concern mustbe present at the time of testing for the KOER on demand self-test to detect the concern. When aconcern is detected, a DTC is output on the data link at the end of the test as requested by thescan tool.

Brake Pedal Position (BPP) Test

The BPP test checks the ability of the EEC system to detect a change of state in the BPP switch.The brake pedal is briefly applied and released on all vehicles equipped with a BPP input. This isdone during a KOER on demand self-test.




Power Steering Pressure (PSP) Test

The PSP test checks the ability of the EEC system to detect a change in the power steeringsystem fluid pressure. The steering wheel is briefly turned at least 1/4 of a revolution on vehiclesequipped with a PSP switch or sensor. This is done during a KOER on demand self-test.

Transmission Control Switch (TCS) Test

The TCS test checks the ability of the EEC system to detect a change of state in the TCS. Theswitch is briefly cycled on all vehicles equipped with a TCS input. This is done during a KOER ondemand self-test.

Continuous Memory Self-Test

The continuous memory self-test is a functional test of the PCM carried out under any condition(engine running or off) with the key on. Unlike the KOEO and KOER self-tests, which can only beactivated on demand, the continuous self-test is always active. A concern does not need to bepresent when accessing continuous memory self-test DTCs, making the test valuable whendiagnosing intermittent concerns. The vehicle may need to be driven or the OBD drive cyclecompleted to allow the PCM to detect a concern. Refer to On Board Diagnostic (OBD) Drive Cyclein this section for more information. When a concern is stored in memory, a DTC is output on thedata link when requested by the scan tool.

There are two types of continuous DTCs. The first type is an emission-related code whichilluminates the malfunction indicator lamp (MIL) in the instrument cluster. The second is anon-emission related, non-MIL DTC which does not illuminate the instrument cluster indicator.

For emission-related MIL DTCs, the PCM stores the DTC in continuous memory when a concernis detected for the first time. At this point the DTC does not illuminate the MIL and is considered apending code. The purpose of pending codes is to assist in repair verification by reporting apending DTC after one drive cycle. If the same concern is detected after the next drive cycle, theemission-related MIL code illuminates the MIL and sets both a confirmed MIL DTC and apermanent DTC. The MIL remains illuminated even if the concern is intermittent. A permanentDTC is stored until three consecutive passing drive cycles have been completed after a repair andthe MIL turns off, or after a request to clear DTCs has been made using the scan tool and thenext monitoring cycle has completed and passed for that DTC.

Confirmed emission-related MIL DTCs and any non-emission related, non-MIL DTCs are erasedapproximately 40 vehicle warm-up cycles after the concern was last detected, or if the DTCs arecleared by the scan tool.

Pending emission-related MIL DTCs that never detect a concern on a second consecutive drivecycle (and never light the MIL) are not retained in memory for any number of vehicle warm-upcycles; they are immediately cleared when the next monitoring cycle has completed and passedfor that DTC, or until a request to clear DTCs has been made by the scan tool.

Any scan tool that meets OBD requirements can access the continuous memory to retrieveemission-related MIL DTCs. However, not all scan tools access pending and non-emission related,non-MIL DTCs in the same way.




During most diagnostic procedures in this manual, it is required that all DTCs be retrieved andcleared. Permanent DTCs cannot be directly cleared by the scan tool. When a scan tool clearsDTCs, pending and confirmed DTCs are immediately cleared. Permanent DTCs will not clear untilthe next monitoring cycle has completed and passed for that DTC. For additional information, referto Section 1, Powertrain Control Software, Permanent Diagnostic Trouble Code (DTC).



Clear the Continuous Diagnostic Trouble Codes (DTCs) andReset the Emission Monitors Information in the Powertrain

Control Module (PCM)

Description

All on board diagnostic (OBD) scan tools support the clearing of continuous DTCs and resetting ofemission monitors information in the PCM.

The clearing of the continuous DTCs allows the scan tool to command the PCM to clear and resetall emission-related diagnostic information. On some vehicles, DTC P1000 is stored in the PCMuntil all the OBD system monitors or components have been tested to satisfy a drive cycle withoutany other concerns occurring. For more information about a drive cycle, refer to On BoardDiagnostic (OBD) Drive Cycle in this section.

The following events occur when the continuous DTCs and the emission monitors information iscleared from the PCM:

• the number of DTCs is reset

• the DTCs are cleared (on vehicles with permanent DTCs, additional vehicle operation is requiredto complete and pass the appropriate monitors to complete the clearing of permanent DTCs)

• the freeze frame data is cleared

• the diagnostic monitoring test results are reset

• the status of the OBD system monitors is reset



Resetting The Keep Alive Memory (KAM)

Description

Resetting the KAM returns the powertrain control module (PCM) memory to its default setting.Adaptive learning contents such as adaptive airflow, idle speed, refueling event, and fuel trim areincluded. Clear the continuous diagnostic trouble codes (DTCs) in the PCM and reset the emissionmonitors information, is part of a KAM reset. Refer to Clear the Continuous Diagnostic TroubleCodes (DTCs) and Reset the Emission Monitors Information in the Powertrain Control Module(PCM) in this section. Both can be useful in post-repair testing.

After the KAM has been reset, the vehicle may exhibit certain driveability concerns. It is necessaryto allow the engine to idle at normal operating temperature with the A/C off for 2 minutes. Thendrive the vehicle to allow the PCM to learn the values for optimum driveability and performance.

This function may not be supported by all scan tools. Refer to the scan tool manufacturer’sinstruction manual.

If an error message is received or the scan tool does not support this function, disconnecting thebattery ground cable for a minimum of 5 minutes may be used as an alternative procedure onsome vehicles.



On Board System Readiness (OSR) Test

Description

All on board diagnostic (OBD) scan tools display the on board system readiness (OSR) test. TheOSR displays the supported monitors on the vehicle and the status of all monitors (complete or notcomplete) at that time. Fuel, misfire, and comprehensive component monitors (CCMs) runcontinuously and always display a YES status. Clearing the continuous diagnostic trouble codes(DTCs) and resetting the emission monitors information in the powertrain control module (PCM), orresetting the keep alive memory (KAM) causes the non-continuous monitors to change to a NOstatus.

A detailed description of completing the OBD monitors is found in this section. Refer to On BoardDiagnostic (OBD) Drive Cycle.



Output State Control (OSC)

Description

WARNING: Safety must be observed when using OSC. Failure to follow theseinstructions may result in personal injury.

The OSC aids in diagnosing output actuators associated with the powertrain control module (PCM)for the engine. This mode allows the technician to command the individual actuator state. Forexample, the output can be enabled or disabled, the duty cycle or the angle of the output can beincreased or decreased. OSC is used to help test the electrical, hydraulic or mechanicalcomponents of the vehicle. This function is supported by the vehicle strategy but may not bepresent on all vehicles or available on all scan tools.

Retrieve the continuous codes and carry out a key on, engine off (KOEO) and key on, enginerunning (KOER) on demand self-test before using any OSC. Any diagnostic trouble codes (DTCs)related to the transmission range (TR) sensor, output shaft speed (OSS) sensor or the vehiclespeed sensor (VSS) must be fixed or the PCM does not allow the OSC to operate.

Each OSC function has a unique set of vehicle operating requirements that the technician isrequired to meet before operating the OSC. If the vehicle requirements are not met whilecommanding the OSC value, an error message appears. When the error message is received,OSC is canceled.

To confirm the scan tool sent the OSC value and the PCM has accepted the OSC substitution, acorresponding parameter identification (PID) for each OSC parameter must be monitored.

One Touch Integrated Start System

Some vehicles are equipped with one touch integrated start system. It may be necessary todisable the one touch integrated start system to carry out diagnostic procedures that requireextended cranking. Connect the scan tool, access the PCM and select the one touch integratedstart system control PID to disable the system.



Output Test Mode (OTM)

Description

WARNING: Safety must be observed when using OTM.

— When all outputs are on, the electric fuel pump is briefly energized. Make sure the fuelsystem is intact and is not being repaired at this time.

— When low speed or high speed fan control(s) are turned on, make sure the fan bladesare clear of any obstruction.

Failure to follow these instructions may result in personal injury.

The OTM aids in diagnosing output actuators associated with the powertrain control module(PCM). This mode allows the technician to energize and de-energize most of the system outputactuators on command. When entering OTM, the outputs can be turned off and on withoutactivating the fan control. The low and high speed fan controls may be turned on separatelywithout energizing the other outputs. This function is supported by each vehicle strategy and maynot be available on all scan tools.

As a safety precaution, OTM defaults to the off state after 10 minutes, and the fuel pump off stateafter approximately 7-10 seconds. OTM also turns off after the vehicle is started or after cyclingthe key OFF then ON.



Parameter Identification (PID)

Description

The PID mode allows access to powertrain control module (PCM) information. This includesanalog and digital signal inputs and outputs along with calculated values and the system status.There are two types of PID lists available and both are used throughout this manual. The first isthe generic (J1979) OBD PID list. This is a standard set of PIDs that all scan tools must be able toaccess. The second is a Ford specific (J2190) list which can be accessed by an appropriate scantool. When accessing any of these PIDs, the values are continuously updated. The generic or FordPID list provides definitions and values in appropriate units. For more information, refer to theSociety of Automotive Engineers (SAE) document J2205.

Generic OBD PID List

An X in the Freeze Frame column denotes both a mode 1 and mode 2 PID (real time and freezeframe).

MeasurementFreeze Frame Acronym Description Units

X APP D Accelerator Pedal Position D %

X APP E Accelerator Pedal Position E %

X APP F Accelerator Pedal Position F %

X BARO Barometric Pressure kPa

X CATEMP11 Catalyst Temperature Bank 1, Sensor 1 Degrees




X CLRDIST Distance Since Codes Cleared Km/mi

X CLRWRMUP Number of Warm Ups Since DTCs Cleared Units

X ECT Engine Coolant Temperature Degrees

X EGRPCT Commanded EGR %

X EGR ERR EGR Error %

X EVAP VP Evaporative System Vapor Pressure Pa

X EQ RAT Commanded Equivalence Ratio Unit

X FLI Fuel Level Input %

X FRP Fuel Rail Pressure kPa

X FUEL SYS1 Fuel System Feedback Control Status Bank 1 Open Loop /Closed Loop

X FUEL SYS2 Fuel System Feedback Control Status Bank 2 Open Loop /Closed Loop

X IAT Intake Air Temperature Degrees

X LOADa Calculated Engine Load %

X LOAD ABS Absolute Load Value %

X LONGFT1 Current Bank 1 Fuel Trim Adjustment %(kamref1) From Stoichiometry Which IsConsidered Long Term

(Continued)




MeasurementFreeze Frame Acronym Description Units

X LONGFT2 Current Bank 2 Fuel Trim Adjustment %(kamref2) From Stoichiometry Which IsConsidered Long Term

X MAF Mass Air Flow Rate g/s-lb/min

X MAP Manifold Absolute Pressure Volts/kPa/PSI/inHg

X MIL DIST Distance Traveled with MIL ON Kilometer

X O2S11 Bank 1 Upstream Oxygen Sensor (11) Volts

X O2S12 Bank 1 Downstream Oxygen Sensor (12) Volts


X O2S21 Bank 2 Upstream Oxygen Sensor (21) Volts



OBDSUP On Board Diagnostic System OBD IIOBD IOBD

Combination ofor None

X PTO Power Take-Off Status On/Off

X RPM Revolutions Per Minute RPM

X RUNTM Run Time Seconds

X SHRTFT1 Current Bank Fuel Trim Adjustment (lambse1) %From Stoichiometry Which Is Considered ShortTerm

X SHRTFT2 Current Bank 2 Fuel Trim Adjustment %(lambse1) From Stoichiometry Which IsConsidered Short Term

X SPARKADV Spark Advance Requested Degrees

X SPARK ACTUAL Spark Advance Actual Degrees

X TAC PCT Commanded Throttle Actuator %

X TP Throttle Position %

X TP REL Relative Throttle Position %

VSS Vehicle Speed Sensor km/h-mph

a Percent engine load adjusted for atmospheric pressure.

Ford PID List

Note: This is not a complete list of Ford PIDs available. This is a list of Ford PIDs in this manual.




PID Description Ford Units

AAT Ambient Air Temperature Degrees

AAT V Ambient Air Temperature Voltage Volts

ACP V A/C Pressure Sensor Voltage Volts

ACP PRESS A/C Pressure Sensor Pressure Pressure

APP Accelerator Pedal Position Percent

APP1 Accelerator Pedal Position 1 Volts



APP MAXDIFF Maximum Difference between APP1 and APP2 Degrees

APP MODE Accelerator Pedal Position Mode Pedal Position

AXLE Axle Ratio Ratio

B+ Battery Voltage Volts

BARO Barometric Pressure Sensor Frequency/Pressure

BOO Brake Pedal Position (BPP) Switch On/Off

BOO1 Brake Pedal Position (BPP) Switch On/Off

BOO2 Brake Pressure Applied On/Off

BPA Brake Pressure Applied (BPA) On/Off

BPP/BOO Brake Pedal Position (BPP) Switch On/Off

CAC T Charge Air Cooler Temperature Degrees F

CAC V Charge Air Cooler Voltage Volts

CAT EVAL Catalyst Evaluated Yes/No

CHT Cylinder Head Temperature Input Volt/Degrees F

CLRDIST Distance Since DTCs Cleared Miles

CLRWRMUP Number of Warm-ups Since DTCs Cleared Count

CPP BOT Clutch Pedal at or Near Bottom of Travel Yes/No

CPP Clutch Pedal Position Switch Input On/Off

CPP/PNP Clutch Pedal Position/Park Neutral Position Switch Input Neutral/Drive

DECHOKE Crank Fueling Disabled Yes/No

DPFEGR Differential Pressure Feedback EGR Input Volts

ECT Engine Coolant Temperature Input Volts/Degrees F

EGRMC1F EGR Motor Control Fault Yes/No




EGRMDSD Electric EGR Motor Commanded in Steps On/Off

EGRPCT Commanded EGR Percent

EGRVR EGR Valve Vacuum Control Percent

EGR EVAL EGR Evaluated Yes/No

EGR STEP EGR Valve Motor Position Position

EONV RDY EVAP Monitor Test Ready at Next Key Off Ready/Not Ready(Continued)





EOT Engine Oil Temperature Sensor Input Volts/Degrees F

EOT F Engine Oil Temperature Sensor Fault Fault/No Fault

EQ RAT11 Equivalence Ratio Lambda Bank 1, Sensor 1 Ratio

EQ RAT21 Equivalence Ratio Lambda Bank 2, Sensor 1 Ratio

ETC ACT Electronic Throttle Control Actual Degrees

ETC DSD Electronic Throttle Control Desired Degrees

ETC TRIM Electronic Throttle Control Trim Degrees

EVAP020C Evaporative Emissions Monitor Yes/No

EVAP020D Evaporative Emissions Monitor Allow/Disallow

EVAP020R Evaporative Emissions Monitor Ready/Not Ready

EVAPCP Evaporative Emissions Canister Purge Valve Percent/On/Off

EVAPCV Evaporative Emissions Canister Purge Vent Control Percent/On/Off

EVAPCV F Evaporative Emissions Canister Purge Vent Fault Fault/No Fault

EVAPSOAK Evaporative Emissions Monitor Soak Conditions are Met Yes/No

EVAPSTA Evaporative Emissions Monitor Completed Cycle Status

EVAP ACTIVE Evaporative Emissions Activation Switch Position at Start Detection Yes/No

EVAP COMLIN F Evaporative Emissions Module Communication Line Status Fault/No Fault

EVAP EVAL Evaporative Emissions Monitor Evaluated Yes/No

EVAP SWITCH Evaporative Emissions Actual Switch Position Open/Closed

EVMV Electronic Vapor Management Valve Commanded Current Current

FAN Engine Cooling Fan Operation On/Off

FANDC Variable Speed Fan Duty Cycle Percent

FAN DSD Fan Speed Desired Percent

FANSS Fan Speed Sensor Signal RPM

FANVAR Variable Speed Fan Output Percent

FANVAR F Variable Speed Fan Output Fault Fault/No Fault

FCIL Fuel Cap Indicator Light On/Off

FF INF Inferred Flex Fuel Percent

FLI Fuel Level Indicator Input Percent

FP Fuel Pump Duty Cycle Percent

FP Fuel Pump On/Off

FPM Fuel Pump Secondary Monitor Percent/On/Off

FPM2 Fuel Pump Secondary 2 Monitor Percent/On/Off

FPM STAT Fuel Pump Monitor Status Fault/No Fault

FRP Fuel Rail Pressure Input Volts/Pressure

FRP DSD Fuel Rail Pressure Desired Pressure

FRT Fuel Rail Temperature Degrees F/Volts

FTP Fuel Tank Pressure Input Volts/Pressure

FTP H2O Fuel Tank Pressure Input Pressure

FTP INF Inferred Fuel Tank Pressure Pressure(Continued)





FUELPW1 Injector Pulse Width Bank 1 Time

FUELPW2 Injector Pulse Width Bank 2 Time

FUELSYS Fuel System Status Open Loop/Closed Loop

F VCV Fuel Volume Control Valve Percent

GEAR Transmission Gear Status Gear

HFC High Speed Fan Control On/Off

HTR11 Bank 1 Sensor 1 HO2S Heater Control On/Off

HTR11F Bank 1 Sensor 1 HO2S Heater Circuit Fault Yes/No


HTR12F Bank 1 Sensor 2 HO2S Heater Circuit Fault Fault/No Fault






HTRCM11 Bank 1 Sensor 1 O2S Heater Circuit Current Current




HTRX1 HO2S Sensor 1 (Upstream) Heater Control On/Off

HTRX2 HO2S Sensor 2 (Downstream) Heater Control On/Off

HO2S11 Bank 1 Sensor 1 HO2S Input Volts





IAC Idle Air Control Percent

IACTRIM Short Term Airflow Trim Numeric Value

IAT Intake Air Temperature Input Degrees F/Volts

IAT2 Intake Air Temperature Sensor 2 Input Degrees F/Volts

IGN R/S Ignition Switch Run/Start On/Off

IMRC Intake Manifold Runner Control On/Off

IMRC F Intake Manifold Runner Control Fault Yes/No

IMRC1M Intake Manifold Runner Control Monitor Input Bank 1 Volts

IMRCM Intake Manifold Runner Control Monitor Input Volts

IMTV Intake Manifold Tuning Valve Control Percent

INJ1F-8F Fuel Injector Primary Fault (Cylinders 1-8) Yes/No

INJ9F-10F Fuel Injector Primary Fault (Cylinders 9 and 10) Yes/No

INJPWR M Injectors Circuit Voltage Monitor Volts(Continued)





KNOCK Knock Sensor Signal Count

KNOCK1 Knock Sensor 1 Signal Count

KNOCK2 Knock Sensor 2 Signal Count

LFC Low Speed Fan Control On/Off

LOAD Calculated Engine Load Percent

LONGFT1 Long Term Fuel Trim Bank 1 Percent

LONGFT2 Long Term Fuel Trim Bank 2 Percent

MAF Mass Airflow Rate Input Frequency/Volts/MassFlow

MAP Intake Manifold Absolute Pressure Frequency/Volts/ Pressure

MAP DMD Manifold Absolute Pressure Demanded Pressure

MIL Malfunction Indicator Lamp Control On/Off

MIL DIS Distance Since MIL was Activated Miles

MISFIRE Misfire Status Yes/No

MP LRN Learned Misfire Correction Profile Yes/No

NM Number of Misfires Count

NUM Misfire Events During Latest Misfire Cycle Count

OUTDR TMP Outdoor Air Temperature Degrees

O2BANK1 Bank 1 O2S Status Rich/Lean

O2BANK2 Bank 2 O2S Status Rich/Lean

O2S11 Bank 1 Sensor 1 O2S Input Volts

O2 DS DISBL Downstream Oxygen Sensor Fuel Control Disabled Yes/No

O2 DS1 ERR Downstream Closed Loop Input Error Bank 1 Volts

O2 DS2 ERR Downstream Closed Loop Input Error Bank 2 Volts

O2S11 CUR Bank 1 Sensor 1 Current Current

O2S11 HTR Commanded Duty Cycle for the O2S11 Heater Output Percentage

O2S11 IMPED O2S11 Sensor Impedance Volts

O2S11 READY O2S11 Is Warm and Ready to Operate Yes/No

O2S11 STAT O2S11 Status Fault/No Fault

O2S11 TR O2 Sensor Trim Circuit Resistance 11 NTK Sensor Resistance



O2S21 CUR Bank 2 Sensor 1 Current Current

O2S21 HTR Commanded Duty Cycle for the O2S21 Heater Output Percentage

O2S21 IMPED O2S21 Sensor Impedance Volts

O2S21 READY O2S21 Is Warm and Ready to Operate Yes/No

O2S21 STAT O2S21 Status Fault/No Fault

O2S21 TR O2 Sensor Trim Circuit Resistance 21 NTK Sensor Resistance


O2S EVAL Oxygen Sensor Circuits Evaluated Yes/No(Continued)





O2SHTR EVAL Oxygen Sensor Heater Circuits Evaluated Yes/No

OD CANCL Overdrive Cancel Function On/Off

OSS Output Shaft Speed RPM

OSS SRC Output Shaft Speed RPM

OTS STAT One Touch Integrated Start System Status Enabled/Disabled

PATSENABL Passive Anti-Theft System Status Enabled/Disabled

PCVHC Positive Crankcase Ventilation Heater Control Percent

PCVHC B Positive Crankcase Ventilation Heater B Percent

PSP Power Steering Pressure Switch Input High/Low

PSP Power Steering Pressure Input Volts

PSP V Power Steering Pressure Input Volts

PTO Power Take Off Status Input On/Off

PTOLOAD Power Take Off Engage Input Yes/No

PTOIR V Power Take Off RPM Select Input Volts

PTOIL Power Take Off Indicator Lamp Output On/Off

RO2FT1 Rear O2 Fuel Trim - Bank 1 Percentage

RO2FT2 Rear O2 Fuel Trim - Bank 2 Percentage

RPM Engine Speed Based Upon CKP Input RPM

RPMDSD RPM Desired RPM

SCBC Supercharger Bypass Control On/Off

SHRTFT Short Term Fuel Trim Percent

SHRTFT1 Short Term Fuel Trim Bank 1 Percent

SHRTFT2 Short Term Fuel Trim Bank 2 Percent

SPARKADV Spark Advance Degrees

SPKDUR 1-8 Spark Duration (Cylinders 1-8) Time

STRT RLY Starter Relay Enabled/Disabled

SYNC CMP and CKP Synchronized Yes/No

TCIL Transmission Control Indicator Lamp Clutch Control Status On/Off

TCS Transmission Control Switch (TCS) Yes/No

TCSS Transfer Case Speed Sensor MPH

TFT Transmission Fluid Temperature Input Volts/Degrees F

TFTV Transmission Fluid Temperature Input Volts

THROTTLE CMD Commanded Throttle Actuator Control Percent

TIP PRES BOOST Throttle Inlet Pressure Measured (Boost Actual) kPa/psi

TIP PRES DSD Throttle Inlet Pressure Desired (Boost Requested) kPa/psi

TIP PRES V Throttle Inlet Pressure Sensor Voltage Volts

TORQUE Net Torque Into Torque Converter Torque

TP Throttle Position Input Volts/Percent

TPCT Lowest Closed Throttle Voltage Volts

TP MAXDIFF Maximum Angle Difference between TP1 and TP2 Degrees(Continued)





TPMODE Throttle Position Closed/Part/Wide Open Throttle

TP1 Throttle Position 1 Voltage Volts

TP2 Throttle Position 2 Voltage Volts

TP B Absolute Throttle Position B Percent

TP1 ADP CLSD Throttle Position 1 Adaption Voltage Closed Stop Volts

TP1 ADP LIMP Throttle Position 1 Adaption Voltage at Limp Home Volts

TP1 ADP MINAIR Throttle Position 1 Adaption Volt Minimum Air Flow Volts

TP2 ADP CLSD Throttle Position 2 Adaption Voltage Closed Stop Volts

TP2 ADP LIMP Throttle Position 2 Adaption Voltage at Limp Home Volts

TQ CNTRL Torque Fuel/Spark Limiting Status Text

TR Transmission Selector Position Input Status Position

TR1 Transmission Range Sensor 1 Open/Closed




TR V Transmission Selector Position Input Status Volts

TR D Transmission Selector Position Input Status (Digital) Binary

TRIP CNT OBD II Trips Completed Count

TURBO BP1 STAT Turbocharger Bypass 1 Status Fault/No Fault

TURBO BP2 STAT Turbocharger Bypass 2 Status Fault/No Fault

TURBO BPASS Turbocharger Bypass Valve Percent

TURBO BPASS 2 Turbocharger Bypass Valve 2 Percent

TURBO OVER Turbocharger Overboost Condition Fault/No Fault

TURBO UNDER Turbocharger Underboost Condition Fault/No Fault

TWGATE STAT Turbocharger Wastegate Status Fault/No Fault

VCTADV Variable Cam Timing Advance Degrees

VCTADV2 Variable Cam Timing Advance 2 Degrees

VCTADVERR Variable Cam Timing Advance Error Degrees

VCTADVERR2 Variable Cam Timing Advance 2 Error Degrees

VCTDC Variable Cam Timing Advance Duty Cycle Percent

VCTDC2 Variable Cam Timing Advance Duty Cycle Percent

VCT EXH ACT1 Actual Exhaust B Camshaft Position Bank 1 Degrees

VCT EXH ACT2 Actual Exhaust B Camshaft Position Bank 2 Degrees

VCT EXH DC1 Exhaust B Camshaft Position Duty Cycle Bank 1 Percent

VCT EXH DC2 Exhaust B Camshaft Position Duty Cycle Bank 2 Percent

VCT EXH DIF1 Exhaust B Camshaft Desired Minus Actual Bank 1 Degrees

VCT EXH DIF2 Exhaust B Camshaft Desired Minus Actual Bank 2 Degrees

VCT EXH DSD VCT Exhaust Angle Desired Degrees

VCT EXH DSD1 VCT Exhaust Angle Desired Bank 1 Degrees(Continued)





VCT INT ACT1 Actual Intake A Camshaft Position Bank 1 Degrees

VCT INT ACT2 Actual Intake A Camshaft Position Bank 2 Degrees

VCT INT DC1 Intake A Camshaft Position Duty Cycle Bank 1 Percent

VCT INT DC2 Intake A Camshaft Position Duty Cycle Bank 2 Percent

VCT INT DIF1 Intake A Camshaft Desired Minus Actual Bank 1 Degrees

VCT INT DIF2 Intake A Camshaft Desired Minus Actual Bank 2 Degrees

VCT INTK DSD VCT Intake Angle Desired Degrees

VCT INTK DSD1 VCT Intake Angle Desired Bank 1 Degrees

VCTSYS Variable Cam Timing System Status Open/Closed

VCT1 F Variable Cam Timing Fault Fault/No Fault

VCT2 F Variable Cam Timing 2 Fault Fault/No Fault

VPWR Vehicle Power Voltage Volts

VREF Vehicle Reference Voltage Volts

VSS Vehicle Speed Speed



Freeze Frame Data

Description

Freeze frame data allows access to emission-related values from specific generic parameteridentification (PID). These values are stored when an emission-related diagnostic trouble code(DTC) is stored in continuous memory. This provides a snapshot of the conditions that werepresent when the DTC was stored. Once one set of freeze frame data is stored, this data remainsin memory even if another emission-related DTC is stored, with the exception of misfire or fuelsystem DTCs. Once freeze frame data for a misfire or fuel system DTC is stored it overwrites anyprevious data, and freeze frame data is no longer overwritten. When a DTC associated with thefreeze frame data is erased or the DTCs are cleared, new freeze frame data can be stored again.In the event of multiple emission-related DTCs in memory, always note the DTC for the freezeframe data.

FREEZE FRAME DATA TABLE

Acronym Description Measurement Units

APP D Accelerator Pedal Position D %

APP E Accelerator Pedal Position E %

APP F Accelerator Pedal Position F %

BARO Barometric Pressure kPa

CATTEMP11 Catalyst Temperature Bank 1, Sensor 1 Degrees

CATTEMP21 Catalyst Temperature Bank 2, Sensor 1 Degrees

CLRDIST Distance Since Codes Cleared Km/mi

ECT Engine Coolant Temperature Degrees

EQ RAT Commanded Equivalence Ratio Unit

EQ RAT11 Lambda Value Bank 1, Sensor 1 Unit

EQ RAT21 Lambda Value Bank 2, Sensor 1 Unit

EVAPPCT Commanded Evaporative Purge %

FLI Fuel Level Input %

FRP Fuel Rail Pressure kPa

FUELSYS1 Open/Closed Loop 1 OL/CL/OL DRIVE/OL FAULT/CL FAULT

FUELSYS2 Open/Closed Loop 2 OL/CL/OL DRIVE/OL FAULT/CL FAULT

IAT Intake Air Temperature Degrees

LFT1 Long Term Fuel Bank 1 %

LFT2 Long Term Fuel Bank 2 %

LOAD Calculated Load Value %

MAF Mass Air Flow Rate g/s

MAP Manifold Absolute Pressure Volts/kPa/PSI/inHg

O2S11 Bank 1 Upstream Oxygen Sensor (11) Volts/mA

O2S12 Bank 1 Downstream Oxygen Sensor (12) Volts

O2S21 Bank 2 Upstream Oxygen Sensor (21) Volts/mA

O2S22 Bank 2 Downstream Oxygen Sensor (22) Volts

RPM Engine RPM RPM(Continued)



Freeze Frame Data

FREEZE FRAME DATA TABLE

Acronym Description Measurement Units

RUNTM Run Time Seconds

SFT1 Short Term Fuel Bank 1 %

SFT2 Short Term Fuel Bank 2 %

SPARKADV Spark Advance Degrees

TAC PCT Commanded Throttle Actuator %

TP Absolute Throttle Position %

TP REL Relative Throttle Position %

VS Vehicle Speed km/h-mph

WARMUPS Number of Warmups Since Code Cleared Units

Some unique PIDs are stored in the keep alive memory (KAM) of the powertrain control module(PCM) to help in diagnosing the root cause of misfires. These PIDs are collectively called misfirefreeze frame (MFF) data. These parameters are separate from the generic freeze frame datastored for every MIL code. They are used for misfire diagnosis only. The MFF data could be moreuseful for misfire diagnosis than the generic freeze frame data. It is captured at the time of thehighest misfire rate, not when the DTC is stored at the end of a 200 or 1,000 revolution block(generic freeze frame data for misfire can be stored minutes after the misfire actually occurred).

The MFF PIDs are supported on all vehicles, but may not be available on all scan tools becauseenhanced PID access may vary by scan tool manufacturer.

MISFIRE FREEZE FRAME PIDs

PID Name Description Measurement Units

MFF EGR EGR DPFE Sensor at the time of Misfire Volts

MFF IAT Intake Air Temperature at the time of Misfire Degrees

MFF INGEAR Transmission In Gear at time of Misfire Yes/No

MFF LOAD Engine Load at the time of Misfire %

MFF PNP Park/Neutral Position at time of Misfire Mode

MFF RNTM Engine Running Time at the time of Misfire Time

MFF RPM Engine RPM at the time of Misfire RPM

MFF RUN Engine Running Time at time of Misfire Time

MFF SOAK Engine Off Soak Time at the time of Misfire Time

MFF TCC Torque Converter Clutch at time of Misfire Yes/NoLOCK

MFF THR Throttle Angle at time of Misfire %ANG

MFF TP Throttle Position at time of Misfire Volts

MFF TRIP Number of Driving Cycles at the time of Number of TripsMisfire (at least one 1,000 rev block)

MFF VSS Vehicle Speed at the time of Misfire km/h-mph

MP LRN Learned Misfire Correction Profile Yes/No



Flash Electrically Erasable Programmable Read OnlyMemory (EEPROM)

Description

The EEPROM is contained in an integrated circuit internal to the powertrain control module (PCM).The EEPROM contains the vehicle strategy including calibration information specific to the vehicle,and is capable of being programmed or flashed repeatedly.

As part of the calibration there is an area referred to as the vehicle identification (VID) block. TheVID block is programmed when installing a new PCM as described under Programming the VIDBlock for a Replacement PCM. Failure to carry out this procedure may generate DTC P1635 orP1639. The VID block in an existing PCM can also be tailored to accommodate various hardwareor parameter changes made to the vehicle since production. Failure to carry out this procedureproperly may generate DTC P1635, Tire or Axle Ratio out of Acceptable Range. An incorrect tireor axle ratio is one of the main causes for DTC P1639. This is described under Making Changesto the VID Block and also under Making Changes to the PCM Calibration. The VID block containsmany items used by the strategy for a variety of functions. Some of these items include the vehicleidentification number (VIN), octane adjust, fuel octane, fuel type, vehicle speed limit, tire size, axleratio, the presence of speed control, and 4-wheel drive electronic shift-on-the-fly (ESOF) versusmanual shift-on-the-fly (MSOF). Only items applicable to the vehicle hardware and supported bythe VID block are displayed on the scan tool.

When changing items in the VID block, the strategy places range limits on certain items such astire and axle ratio. The number of times the VID block may be reconfigured is limited. When thislimit is reached, the scan tool displays a message indicating the need to flash the PCM again toreset the VID block. For Fiesta, the body control module communicates the VIN to the PCM. Whena new PCM is installed, the PCM obtains the VIN the first time the ignition is turned to the ONposition. If there is a concern with the VIN not being received or being invalid, DTC P0630 is set.

On selected vehicles equipped with permanent DTC reporting capabilities, neutral profile correctionshould be learned after a PCM replacement in order to activate the misfire monitor. This can beaccomplished using the Misfire Monitor Neutral Profile Learn function on the scan tool.

Programming can be carried out by a local Ford dealer or any non-Ford facility. Refer to the scantool manufacturer’s instruction manual for details.

Neutral Profile Correction — Fiesta

In order for the misfire detection system to function correctly, any mechanical inaccuracies in thecrankshaft position (CKP) sensor must be learned by the PCM. Neutral profile should be relearnedany time the PCM, CKP sensor or the crankshaft pulse wheel is replaced or major engine repairshave been completed.

Misfire detection is active before profile learning has been completed using default thresholds.When profile has been learned the vehicle specific thresholds are then used.

Neutral profile correction is learned on the road by decelerating with deceleration fuel shut off(DFSO) active. Profile correction is continuos throughout the lifetime of the vehicle, when ever thelearning conditions are met adaption takes place. The neutral profile correction can only becompleted using the OBD Drive Cycle. Refer to the On Board Diagnostic (OBD) Drive Cycle in thissection for additional information.




Neutral Profile Correction — All Others

In order for the misfire detection system to function correctly, any mechanical inaccuracies in thecrankshaft position (CKP) sensor must be learned by the PCM. This information is stored innon-volatile memory (NVM) in the PCM. It is not cleared when the keep alive memory (KAM) isreset.

Neutral profile learning is accomplished using the scan tool any time a PCM is replaced. It shouldalso be relearned any time the CKP sensor or the crankshaft pulse wheel is replaced or majorengine repairs have been completed.

To determine if the neutral profile learning has been completed, check the MP LRN parameteridentification (PID) using the scan tool. The PID should read YES if the neutral profile learning hasbeen completed. If the PID reads NO, complete the neutral profile learning prior to diagnosing anymisfire DTCs.

Programming the VID Block for a Replacement PCM

The VID block on a replacement PCM is blank and requires programming. There are twoprocedures available. The first is an automatic data transfer from the old PCM to the new PCM,the second is manual data entry into the new PCM.

Automatic data transfer is carried out if the old PCM is capable of communicating. This is done byusing a scan tool to retrieve data from the old PCM before removing it from the vehicle. Thestored data can be downloaded to the new PCM after it has been installed. For Fiesta, the bodycontrol module communicates the vehicle identification number (VIN) to the PCM. When a newPCM is installed, the PCM obtains the VIN the first time the ignition is turned to the ON position. Ifthere is a concern with the VIN not being received or being invalid, DTC P0630 is set.

Carry out manual data entry if the old PCM is damaged or incapable of communicating. Removeand install a new PCM. Using a compatible scan tool, select and carry out the module/parameterprogramming, referring to the scan tool manufacturer’s instruction manual. Make certain that allparameters are included. Failure to properly program tire size in revolutions per mile, (rev/mileequals 63,360 divided by the tire circumference in inches), axle ratio, 4x4 or 4x2, or MSOF andESOF may result in DTCs P1635 and P1639. You may be instructed to contact the As-Built DataCenter for the information needed to manually update the VID block with the scan tool. Contactthe center only if the old PCM cannot be used or the data is corrupt. For Ford and Lincoln Mercurytechnicians, contact your National Hotline or the Professional Technician Society (PTS) web sitefor As-Built data listed under the Service Publications Index. Non-Ford technicians use theMotorcraft web site at www.motorcraft.com. From the Motorcraft home page, use the searchfunction to find the Module Programming or As-Built Data.

For Ford and Lincoln Mercury technicians, check the Programmable Module Installation link on thePTS web site for quick Programmable Module data information by vehicle.

Making Changes to the VID Block

A programmed PCM may require changes to be made to certain VID information to accommodatethe vehicle hardware. Refer to Module Reprogramming on the scan tool.




Making Changes to the PCM Calibration

At certain times, the EEPROM needs to be completely reprogrammed. This is due to changesmade to the strategy or calibration after production or the need to reset the VID block because ithas reached its limit. Refer to PCM or Module Reprogramming on the scan tool.



Diagnostic Monitoring Test Results Mode 6

Mode 6 allows access to the results of on board diagnostic (OBD) monitor diagnostic test results.The test values are stored at the time of the particular monitor completion. Refer to mode 6 on thescan tool for test information.



On Board Diagnostic (OBD) Drive Cycle

Description of On Board Diagnostic (OBD) Drive Cycle — Fiesta

The following procedure is designed to execute and complete the OBD monitors. To complete aspecific monitor for repair verification, follow steps 1 through 4, then continue with the stepdescribed by the appropriate monitor found under the OBD Monitor Exercised column. For theEVAP monitor to run, the ambient air temperature must be between 3.75 to 40°C (38.8 to 104°F),and the altitude below 2,438 meters (8,000 feet).

The OBD drive cycle is carried out using a scan tool. Refer to the manufacturer’s instructionmanual for each described function.

A detailed description for clearing the DTCs is found in this section. Refer to Clear The ContinuousDiagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The PowertrainControl Module (PCM).

Drive Cycle Recommendations

WARNING: Strict observance of posted speed limits and attention to drivingconditions are mandatory when proceeding through the following drive cycles. Failure tofollow these instructions may result in personal injury.

1. Most OBD monitors complete more readily using a steady foot driving style during cruise oracceleration modes. Operating the throttle in a smooth fashion minimizes the time required formonitor completion.

2. The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable.

For best results, follow each of the following steps as accurately as possible:

OBD MonitorExercised Drive Cycle Procedure Purpose of Drive Cycle Procedure

Drive Cycle 1. Install the scan tool. Turn the ignition ON Resets the OBD monitor status.Preparation with the engine OFF (do not cycle the ignition).

If needed, select the appropriate vehicle andengine qualifier. Clear the continuous DTCs andreset the emission monitors information in thePCM.

2. Begin to monitor the following PIDs (ifavailable): ECT, OUTDR TMP, EVAPDC, FLIand TP MODE. Start the vehicle withoutreturning the ignition to the OFF position.

3. Idle the vehicle for 30 seconds. Drive at 77to 104 km/h (48 to 65 mph) until the enginecoolant temperature (ECT) is at least 76.7°C(170°F).

(Continued)





Prep for 4. Is the ambient air temperature (AAT) Entry condition for EVAP large leak and purgeMonitor Entry between 3.75 to 40°C (38.8 to 104°F)? If not flow test.

the large leak and purge flow test will notcomplete. It is not possible to bypass the EVAPmonitor and complete the OBD Drive Cycle.

HO2S Cruise between 1500 and 3000 rpm for at least Executes the HO2S monitor.5 minutes. Allow engine to idle for 5 minutes.Accelerate to 70 km/h (43.5 mph) and hold for5 seconds at this speed. Decelerate to 40 km/h(25 mph) with closed throttle (make sure thedeceleration fuel cutoff mode has beenentered).

Catalyst Ensure HHO2S monitor has completed. Executes the catalyst monitor.Accelerate to 70 km/h (43.5 mph) and hold for5 seconds at this speed. Decelerate to 40 km/h(25 mph) with closed throttle (make sure thedeceleration fuel cutoff mode has beenentered). At 40 km/h (25 mph) return to partthrottle with the smallest possible throttlemovement. Repeat 5 times.

EVAP Cruise at speed greater than 5 km/h (3.1 mph) Executes the EVAP Large Leak and Purge Flowfor at least 3 minutes. Idle engine for at least 5 Monitor if ambient air temperature is betweenminutes. 3.75 to 40°C (38.8 to 104°F).

Fuel Monitor Cruise with part throttle at 1500 - 2500 rpm for Executes the fuel monitor.20 minutes. Allow vehicle to idle for 10 minutes.Monitor will complete quicker if a fault ispresent.

Misfire Executes the misfire monitor.Note:The misfire monitor will runbefore profile correction hasbeen learned but for moreaccurate measurements profilecorrection should be learned.

Acceleratre to 104.6 km/h (65 mph), holdsteady throttle for 5 seconds, then decelerate to64.4 km/h (40 mph) with closed throttle and nobrakes (make sure the deceleration fuel cutoffmode has been entered). Repeat 3 times.

Deceleration Accelerate to 104.6 km/h (65 mph), hold steady Executes the deceleration fuel shut off rearFuel Shut Off throttle for 5 seconds, then decelerate to 64.4 HO2S monitor.Rear HO2S km/h (40 mph) with closed throttle and no

Monitor brakes (make sure the deceleration fuel cutoffmode has been entered). Repeat 5 times.

Readiness Access the On Board System Readiness (OBD Determines if any monitor has not completed.Check monitor status) function on the scan tool.

Determine whether all noncontinuous monitorshave completed.

Pending Code With the scan tool, check for pending codes. Determines if a pending code is preventing theCheck Conduct the normal repair procedures for any completion of the OBD drive cycle.

pending code concern.(Continued)





EVAP Small Executes the small leak monitor.Note:Leak Prior to checking for a small

leak, the vehicle should bedriven during the hottest part ofthe day before leaving forovernight soak. A completePCM power down must becompleted prior to starting theengine for the drive cyclepreperation drive. After theignition is turned OFF for theovernight soak the ignition mustnot be turned ON prior tostarting the engine in themorning. When starting thevehicle after the overnight soakthe engine must be startedafter initial ignition ON (do notcycle the ignition). The smallleak test result will be available60 seconds after engine start.

At the end of EVAP large leak and purge flowtest if no fault is found check that NVLD isclosed and purge is active by checking theEVAP ACTIVE and EVAP SWITCH PIDs.Turn the ignition OFF and continue to monitorthe switch position PID. Wait until the PCMpowers down. The NVLD switch position shouldremain closed until the PCM powers down. Toconfirm a small leak the vehicle should be leftoutside overnight.

Description of On Board Diagnostic (OBD) Drive Cycle — All Others

The following procedure is designed to execute and complete the OBD monitors. To complete aspecific monitor for repair verification, follow steps 1 through 4, then continue with the stepdescribed by the appropriate monitor found under the OBD Monitor Exercised column. For theEVAP monitor to run, the ambient air temperature must be between 4.4 to 37.8°C (40 to 100°F),and the altitude below 2,438 meters (8,000 feet). If the OBD monitors must be completed in theseconditions, the powertrain control module (PCM) must detect them once (twice on someapplications) before the EVAP monitor can be bypassed and OBD monitors readied. The EVAPbypassing procedure is described in the following drive cycle.

The OBD drive cycle is carried out using a scan tool. Refer to the manufacturer’s instructionmanual for each described function.




A detailed description for clearing the DTCs is found in this section. Refer to Clear The ContinuousDiagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The PowertrainControl Module (PCM).

Drive Cycle Recommendations

WARNING: Strict observance of posted speed limits and attention to drivingconditions are mandatory when proceeding through the following drive cycles. Failure tofollow these instructions may result in personal injury.

1. Most OBD monitors complete more readily using a steady foot driving style during cruise oracceleration modes. Operating the throttle in a smooth fashion minimizes the time required formonitor completion.

2. The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable.

3. The evaporative monitor can operate only during the first 30 minutes of engine operation.When executing the procedure for this monitor, stay in part throttle mode and drive in a smoothfashion to minimize fuel slosh.

4. When bypassing the EVAP engine soak times, the PCM must remain powered (key ON) afterclearing the continuous DTCs and relearning emission diagnostic information.

For best results, follow each of the following steps as accurately as possible:


Drive Cycle Bypasses the engine soak timer. Resets theNote:Preparation OBD monitor status.To bypass the EVAP soak

timer (normally 6 hours), thePCM must remain poweredafter clearing the continuousDTCs and resetting theemission monitors informationin the PCM.

1. Install the scan tool. Turn the key ON withthe engine OFF. Cycle the key off, then on. Ifneeded, select the appropriate vehicle andengine qualifier. Clear the continuous DTCs andreset the emission monitors information in thePCM.

2. Begin to monitor the following PIDs (ifavailable): ECT, EVAPDC, FLI and TP MODE.Start the vehicle without returning the key to theOFF position.

(Continued)





3. Idle the vehicle for 15 seconds. Drive at 77to 104 km/h (48 to 65 mph) until the enginecoolant temperature (ECT) is at least 76.7°C(170°F).

Prep for 4. Is the intake air temperature (IAT) between Engine warm-up and provides IAT input to theMonitor Entry 4.4 and 37.8°C (40 and 100°F)? If not, PCM.

complete the following steps, but note that step14 is required to bypass the EVAP monitor andcomplete the OBD drive cycle.

HO2S 5. Cruise at 77 to 104 km/h (48 to 65 mph) for Executes the HO2S monitor.at least 5 minutes.

EVAP 6. Cruise at 77 to 104 km/h (48 to 65 mph) for Executes the EVAP monitor if the IAT is10 minutes (avoid sharp turns and hills). NOTE: between 4.4 to 37.8°C (40 to 100°F).To initiate the monitor, the throttle should be atpart throttle, EVAPDC must be greater than75%, and FLI must be between 15 and 85%,and for fuel tanks over 25 gallons FLI must bebetween 30 and 85%.

Catalyst 7. Drive in stop and go traffic conditions. Executes the catalyst monitor.Include 5 different constant cruise speeds,ranging from 40 to 72 km/h (25 to 45 mph) overa 10 minute period.

EGR 8. From a stop, idle for 30 seconds, accelerate Executes the EGR monitor.to 72 km/h (45 mph) at 1/2 to 3/4 throttle, cruiseat steady throttle for 1 minute. Repeat idle,acceleration and cruise 3 times.

CCM (Engine) 9. Bring the vehicle to a stop. Idle with the Executes the idle air control (IAC) portion of thetransmission in drive (neutral for M/T) for 2 comprehensive component monitor (CCM).minutes.

CCM 10. For M/T, accelerate from 0 to 80 km/h (0 to Executes the transmission portion of the CCM.(Transmission) 50 mph), and continue to step 11. For A/T, from

a stop and in overdrive, moderately accelerateto 80 km/h (50 mph) and cruise for at least 15seconds. Stop the vehicle and repeat withoutoverdrive to 64 km/h (40 mph) cruising for atleast 30 seconds. While at 64 km/h (40 mph),activate the overdrive, accelerate to 80 km/h(50 mph) and cruise for at least 15 seconds.Stop for at least 20 seconds and repeat step 10five times.

Misfire, Fuel 11. From a stop, accelerate to 104 km/h (65 Allows learning for the misfire monitor, andand mph), hold steady throttle for 5 seconds, then completion of the deceleration fuel shut off rear

Deceleration decelerate at closed throttle to 64 km/h (40 HO2S monitor.Fuel Shut Off mph) (no brakes), accelerate from 64 Km/h (40Rear HO2S mph) to 104 Km/h (65 mph), hold steady throttle

Monitors for 5 seconds, repeat deceleration 5 times.

Readiness 12. Access the On Board System Readiness Determines if any monitor has not completed.Check (OBD monitor status) function on the scan tool.

Determine whether all non-continuous monitorshave completed. If not, go to step 13.

(Continued)





Pending Code 13. With the scan tool, check for pending Determines if a pending code is preventing theCheck and codes. Conduct the normal repair procedures completion of the OBD drive cycle.

EVAP Monitor for any pending code concern. Otherwise,Bypass Check repeat any incomplete monitor. If the EVAP

monitor is not complete and the IAT was out ofthe 4.4 to 37.8°C (40 to 100°F) temperaturerange in step 4, or the altitude is over 2438 m(8000 ft.), the EVAP bypass procedure must befollowed. Go to Step 14.

EVAP Monitor 14. Park the vehicle for a minimum of 8 hours. Allows the bypass counter to increment to 2.Bypass Repeat steps 2 through 11. Do not repeat step

1.



Intermittent Diagnostic Techniques

Intermittent diagnostic techniques help find and isolate the root cause of intermittent concernsassociated with the electronic engine control (EEC) system. The information is organized to helpfind the concern and carry out the repair. The process of finding and isolating an intermittentconcern starts with recreating a fault symptom, accumulating powertrain control module (PCM)data, and comparing that data to typical values, then analyzing the results. Refer to the scan toolmanufacturer’s instruction manual for the functions described below.

Before proceeding, be sure that:

• Customary mechanical system tests and inspections do not reveal a concern. Mechanicalcomponent conditions can make a PCM system react abnormally.

• Technical Service Bulletins (TSBs) and On-line Automotive Service Information System (OASIS)messages, if available, are reviewed.

• Quick Test and associated diagnostic subroutines have been completed without finding aconcern, and the symptom is still present.

Recreating the Fault

Recreating the concern is the first step in isolating the cause of the intermittent symptom. Athorough investigation should start with the customer information worksheet located in the back ofthis manual. If freeze frame data is available, it may help in recreating the conditions at the time ofa malfunction indicator lamp diagnostic trouble code (MIL DTC). Listed below are some of theconditions for recreating the concern:

CONDITIONS TO RECREATE FAULT

Non-Engine Type Condi-Engine Type Conditions tions

Engine Temperature Ambient Temperature

Engine RPM Moisture Conditions

Engine Load Road Conditions(smooth-bumpy)

Engineidle/accel/deceleration

Accumulating PCM Data

PCM data can be accumulated in a number of ways. This includes circuit measurements with adigital multimeter (DMM) or scan tool parameter identification (PID) data. Acquisition of PCM PIDdata using a scan tool is one of the easiest ways to gather information. Gather as much data aspossible when the concern is occurring to prevent improper diagnosis. Data should beaccumulated during different operating conditions and based on the customer description of theintermittent concern. Compare this data with the known good data values. Refer to Section 6,Typical Diagnostic Reference Values. This requires recording data in four conditions forcomparison: 1) KOEO, 2) Hot Idle, 3) 48 km/h (30 mph), and 4) 89 km/h (55 mph).



Intermittent Diagnostic Techniques

Peripheral Inputs

Some signals may require certain peripherals or auxiliary tools for diagnosis. In some cases, thesedevices can be inserted into the measurement jacks of the scan tool or DMM. For example,connecting an electronic fuel pressure gauge to monitor and record the fuel pressure voltagereading and capturing the data would help find the fault.

Comparing PCM Data

After the PCM values are acquired, it is necessary to determine the concern area. This typicallyrequires the comparison of the actual values from the vehicle to the typical values from Section 6.Refer to Section 6, Typical Diagnostic Reference Values. The charts apply to different vehicleapplications (engine, model, transmission).

Analyzing PCM Data

Look for abnormal events or values that are clearly incorrect. Inspect the signals for abrupt orunexpected changes. For example, during a steady cruise most of the sensor values should berelatively stable. Sensors such as throttle position (TP) and mass air flow (MAF), as well as anRPM that changes abruptly when the vehicle is traveling at a constant speed, are clues to apossible concern area.

Look for an agreement in related signals. For example, if the APP1, APP2, or APP3, changesduring acceleration, a corresponding change should occur in RPM and SPARK ADV PID.

Make sure the signals act in proper sequence. An increase in RPM after the TP1 and TP2increases is expected. However, if the RPM increases without a TP1 and TP2 change, a concernmay exist.

Scroll through the PID data while analyzing the information. Look for sudden drops or spikes in thevalues.



Adaptive Fuel Diagnostic Trouble Code (DTC) DiagnosticTechniques

The Adaptive Fuel DTC Diagnostic Techniques help isolate the root cause of the adaptive fuelconcern. Before proceeding, attempt to verify if any driveability concerns are present. Thesediagnostic aids are meant as a supplement to the pinpoint test steps in Section 5. For adescription of fuel trim, refer to Section 1, Powertrain Control Software, Fuel Trim.

Obtain Freeze Frame Data

Freeze frame data is helpful in duplicating and diagnosing adaptive fuel concerns. The data (asnapshot of certain parameter identification (PID) values recorded at the time the DTC is stored inContinuous Memory) is helpful to determine how the vehicle was being driven when the concernoccurred, and is especially useful on intermittent concerns. Freeze frame data, in many cases,helps isolate possible areas of concern as well as rule out others. Refer to Freeze Frame Data inthis section for a more detailed description of this data.

Using the LONGFT1 and LONGFT2 (Dual Bank Engines) PIDs

The LONGFT1 and LONGFT2 PIDs are useful for diagnosing fuel trim concerns. A negative PIDvalue indicates fuel is being reduced to compensate for a rich condition. A positive PID valueindicates fuel is being increased to compensate for a lean condition. It is important to know thereis a separate LONGFT value used for each RPM and load point of engine operation. Whenviewing the LONGFT1 and LONGFT2 PIDs, the values may change a great deal as the engine isoperating at different RPM and load points. This is because the fuel system may have learnedcorrections for fuel delivery concerns that can change as a function of engine RPM and load. TheLONGFT1 and LONGFT2 PIDs display the fuel trim currently being used at that RPM and loadpoint. Observing the changes in LONGFT1 and LONGFT2 can help when diagnosing fuel systemconcerns. For example:

• A contaminated mass air flow (MAF) sensor results in matching LONGFT1 and LONGFT2correction values that are negative at idle (reducing fuel), but positive (adding fuel) at higherRPM and loads.

• LONGFT1 values that differ greatly from LONGFT2 values rule out concerns that are commonfor both banks (for example, fuel pressure concerns, MAF sensor, etc. can be ruled out).

• Vacuum leaks result in large rich corrections (positive LONGFT1 and LONGFT2 values) at idle,but little or no correction at higher RPM and loads.

• A plugged fuel filter results in no correction at idle, but large rich corrections (positive LONGFT1and LONGFT2 values) at high RPM and load.

Resetting Long Term Fuel Trims

Long term fuel trim corrections are reset by resetting the keep alive memory (KAM). Refer toResetting The Keep Alive Memory (KAM) in this section. After making a fuel system repair, resetthe KAM. For example, if dirty or plugged injectors cause the engine to run lean and generate richlong term corrections, installing new injectors and not resetting the KAM causes the engine to runvery rich. The rich correction eventually leans out during closed loop operation, but the vehiclemay have poor driveability and high carbon monoxide (CO) emissions while it is learning.




DTCs P0171 and P0174 System Too Lean Diagnostic Aids

Note: If the system is lean at certain conditions, then the LONGFT PID would be a positive valueat those conditions, indicating that increased fuel is needed.

The ability to identify the type of lean condition causing the concern is crucial to a correctdiagnosis.

Air Measurement System

With this condition, the engine runs rich or lean of stoichiometry (14.7:1 air/fuel ratio) if thepowertrain control module (PCM) is not able to compensate enough to correct for the condition.One possibility is the mass of air entering the engine is actually greater than what the MAF sensoris indicating to the PCM. For example, with a contaminated MAF sensor, the engine runs lean athigher RPM because the PCM delivers fuel for less air than is actually entering the engine.Example:

• The MAF sensor measurement is inaccurate due to a corroded connector, contaminated or dirtyconnector. A contaminated MAF sensor typically results in a rich system at low airflows (PCMreduces fuel) and a lean system at high airflows (PCM increases fuel).

Vacuum Leaks and Unmetered Air

With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if thePCM is not able to compensate enough to correct for the condition. This condition can be causedby unmetered air entering the engine, or due to a MAF concern. In this situation, the volume of airentering the engine is actually greater than what the MAF sensor is indicating to the PCM.Vacuum leaks normally are most apparent when high manifold vacuum is present (for example,during idle or light throttle). If freeze frame data indicates the fault occurred at idle, a check forvacuum leaks and unmetered air might be the best starting point.

For example, loose, leaking or disconnected vacuum lines, intake manifold gaskets or O-rings,throttle body gaskets, brake booster, air inlet tube, a stuck, frozen or aftermarket positivecrankcase ventilation (PCV) valve, and unseated engine oil dipstick.

Insufficient Fueling

With this condition, the engine runs lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is notable to compensate enough to correct for the condition. This condition is caused by a fuel deliverysystem concern that restricts or limits the amount of fuel being delivered to the engine. Thiscondition is normally apparent as the engine is under a heavy load and at high RPM, when ahigher volume of fuel is required. If the freeze frame data indicates the concern occurs under aheavy load and at higher RPM, a check of the fuel delivery system (checking fuel pressure withengine under a load) is the best starting point. Examples of this include:

• low fuel pressure (fuel pump, fuel filter, fuel leaks, restricted fuel supply lines)

• fuel injector concerns

Exhaust System Leaks




In this type of condition, the engine runs rich of stoichiometry (14.7:1 air/fuel ratio) because thefuel control system is adding fuel to compensate for a perceived (not actual) lean condition. Thiscondition is caused by the heated oxygen sensor (HO2S) sensing the oxygen (air) entering theexhaust system from an external source. The PCM reacts to this exhaust leak by increasing fueldelivery. This condition causes the exhaust gas mixture from the cylinder to be rich. Examples ofthis include:

• exhaust system leaks upstream or near the HO2S

• cracked/leaking HO2S boss

DTCs P0172 and P0175 System Too Rich Diagnostic Aids

Note: If the system is rich at certain conditions, then the LONGFT PID would be a negative valueat that airflow, indicating that decreased fuel is needed.

System rich concerns are caused by fuel system concerns, although the MAF sensor and baseengine (for example, engine oil contaminated with fuel) should also be checked.

Air Measurement System

With this condition, the engine runs rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM isnot able to compensate enough to correct for the condition. One possibility, the MAF sensormeasurement is inaccurate due to a corroded connector, contamination or dirt on the MAF screenor elements. A contaminated MAF sensor typically results in a rich system at low airflows (PCMreduces fuel) and a lean system at high airflows (PCM increases fuel).

Fuel System

With this condition, the engine runs rich of stoichiometry (14.7:1 air/fuel ratio), if the PCM is notable to compensate enough to correct for the condition. This situation causes a fuel deliverysystem that is delivering excessive fuel to the engine.

Examples of this include:

• fuel pressure regulator (mechanical returnless fuel systems) causes excessive fuel pressure(system rich at all airflows), fuel pressure is intermittent, going to pump deadhead pressure, thenreturning to normal after the engine is turned off and restarted.

• fuel injector leaks (injector delivers extra fuel).

• evaporative emission (EVAP) canister purge valve leak (if the canister is full of vapors,introduces extra fuel).

• fuel rail pressure (FRP) sensor (electronic returnless fuel systems) concern causes the sensor toindicate a lower pressure than actual. The PCM commands a higher duty cycle to the fuel pumpdriver module (FPDM), causing high fuel pressure (system rich at all airflows).

Intake Air System




A restriction within any of the following components may be significant enough to affect the abilityof the PCM adaptive fuel control.

• air inlet tube

• air cleaner element

• air cleaner assembly

• resonators

• clean air tube

Base Engine

Engine oil contaminated with fuel can contribute to a rich-running engine.


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