5.2 - ABS Braking System [OCR]

8/10/2019 5.2 - ABS Braking System [OCR]

1/126

Saab 9

S RVI MANUAL

5:

S

braking

system

989


2/126


3/126

599 Alphabetical section guide

59

ASS-system tester

53 Changing the

hr;alke

1fluid

52

Bleeding

the br ke

s y s ~ m

5

ComponeRI remov.allfittiT} g

5 ABS

control:

d escrJpti O:n of

operation

5 Technioal des ori1ptLon

25

Technical

t

5

Special tools

El

D

t

I

I

i

I

I

i


4/126


5/126

Technical data 025-1

ATE

10-14

-30to

+8 0

-22to

+176)

0-1.80 0 - 2610)

140 - 180 2030 -2610)

v

c OF

bar psi)

bar psi)

>

H y d l i a u ~ C IUIl lBft

., . Make

. ,. W or ki ng vol ta ge

11

..

;> Working temperature

Pressures: Brake circuits

- - - - - - - - - - - - - - - - - - - -+ - - _ - - - . : . . . -

- - - . : . .. - _ - - - - - - - - - - - -

Accumulator

Reservoir capacity

litres Iiq qt) 0.8 0.84)

Total capacity

of

brake

system litres Iiq qt)

1.2

1.3)

Brake fluid specification

DOT4

Number of chambers . 3

NO.1 chamber

Static

circuit

NO.2 chamb.er

Dynamic circuit to pump)

NO.3 chamber

Dynamic circuit return from servo)

Filterflow capacity litres/min

I/Iiqqt) 0.5 0.5)

Fluid level indicator

resistance ohm

10

reservoir empty)

ABS-warningswitch resistance ohm 1 reservoir full)

I ...

Type

Ball-valve

0.1-1.0

0.45-14.5)

140 -180 2030 - 2610)

bar psi)

bar psi)

Pressure: Inletside

~ - - - - - - - - - - - - - - - - - + - - - _ : . . . . - - _ - _ : . . . . - - _ - - - - - - - -

Del ivery side

Reliefvalveopening pressure

Power demand

Maximum running time

bar psi)

210 3045)

180 at 160 bar)

2 m in

at

ati me followed

by

10-min pause pump must notbe run

dry

Gas

Nitrogen

Gas pressure at 20C 68F)

bar psi) 80 1160)

Minimum gas pressure

bar psi)

40

580)

Fluid capacity

Iitres I iqqt) 0.25 0.26)

Working pressure range

bar psi)

135

-190 1958- 2755)

Maximum pressure drop

bar psi)

10min 10 145)

Saab900


6/126

025-2

Technical data

Pressure switch:

Breakscircuit

at

bar psi

180

4

2610

58

Makes circu

i ta t

bar psi

140

4

2030

58

Warning-lightswitch:

Breakscircuit

at

bar psi

134

2

1943

29

Makes circuit

at

bar psi

105

2

1523 29

Maximum working pressure

bar psi 180 2610

Power rating

at 12

V W

35

Resistance ohm

5- 7

SoHenoid

v ~ v s

Maximumworking pressure

bar psi

180

40 2610

580

Saab

26

4 19 3

25

20-26 15-19

5-7

36

2.2

34-46

25-34

0.65

0.026

94

0.15-0.70

800-1400

7-18

40

-40to +8 0 -40

to

+176

V

ohm

Va.c.

ohm

W

mm in

Nm Ibfft

Nm

Ibfft

Nm

Ibfft

Powerrati ng

at

12 V

Pressureswitch

Resistance

Flow capacity

at

20C and

100 bar

Accumulator

Hydraulic unit

No.

of

teeth

Wheel sensor - sensor wheel

clearance

Workingvoltage range

Workingtemperatur e range

Resistance

Workingvoltage range

Power rating

Wll eeDselrnsovs

IECU


7/126

ABS-system tester

89965

Pressure sensor included with

S-

system tester

899657 Socket for removal/fitting of pres

sure switch

peci l tools

1 5 1

8996589

Extension lead,

ECU

to ABS-system

tester

8996597

Adaptor hose for connect ing pres

sure sensor

to

hydraulic

unit

Saab


8/126


9/126

echnic l description 5 1

General .

Principles

of

operation.

5 1

500-5

Components 5 11

S

brakes Anti-lock Braking System have

been developed to provide opt imum braking,

with no loss

of

direction or stability, underwidely

varying conditions.

The

stopping distance of a

caris influenced by avarietyoffactors, including

weather conditions, road surface, prevail ing

traffic conditions, braking effort applied.

The SS

system provides modern braking sys

tems with a control funct ion that enables the

maximum braking effect to be exploited in crit i

cal situations, regardless ofthe road conditions.

The

system automatically monitors and mod

ulatesthe brake pressurefor eachfront wheel in

dividually and forthe rearwheelstogetherto pre

vent the wheels from locking.

The

shortestpossi

ble stopping distance istherefore achieved with

out any loss

of

steering control.

The

main advantages of the

S

system are as

follows:

No

loss

of

directional stability

on

braking

l

Steering control retained even when brakes

hard on

o

Shortest possible stopping distance

Reduced tyre wear

Saab900


10/126

500 2 Technical description

To

understand how the ASS system provides op-

timum braking without any loss of directional

Direction

oftravel

stability, we need to examine the forces acting

on a wheel during braking.

Braking force Lateral force

1

All t he forces taken up by the tyre are e ither lateral

forces

or

braking forces

.

On

the adjacent chart, the curve I) shows the re-

lationship between braking force expressed as

a coefficient) and tyre sl ip expressed as a per

centage),.

The braking force is equivalent to the coefficient

of

adhesion, i.e. the friction between the tyre

and the road surface. Each application of a brak

ing force gives rise to a certain degree of slip,

, ranging from 0 when the wheel is rolling freely

to

100

when the wheel is locked.

When the brake is

first

applied, the braking force

increases sharply, but the degree of slip only

gradually, up to a certain l imi t. Beyond

that

point,

the

braking force wil l decrease with in

creasing slip.

li< l :::,.....,--,.,.,.,.,.,=== .....ub-;:.. t - . . : : : i ~ I ~ I : : : : : : I : : : I ~ l m l

the inlet valve, reducing the speed of rota

tion ofthe wheel. The used fluid is replaced by

f lu id s up pl ie d f rom t he servo cy li nd er via t he

main valve.

Phases 2 and 3 are repeated until t he brake

pedal is released or sufficientadhesion between

the tyre and road surface is regained.

The ECU which receives power from the system

relay, is a sealed m odule.

No

attempt must

be

made

to

open it.

The functi

on of

the ECU is to process the informa

tion signals) received from the wheel sensors

and to translate it into control signals

to

the sol

enoid valves. The ECU monitors

most of

the elec

trical components in the

BS

system and also its

own electronic circuitry. It also monitorsthe hyd

raulic pressure in the accumulator and the brake

fluid level in the reservoir.

If a fault is deteqed the ECU wil l cut out the

BS

system, and switch on the SS Anti-lock) warn

ing l ight. If

the

fault could affect

the

conven

t ional braking system in t he car, t he s ta nd ar d

brake warning

light

will also be switched on. This

will occur if the level

in

the brake fluid reservoir

drops too low or ifthe accumulator pressure falls

outside the specified range.

Saab900

To ensure smooth braking, the valves open and

close up twelve

ti

mes a second. Inthe event of

a wire breaking or a short-circuit occurring,

the

valves will reve rt

to their

de-energized position,

making conventio nal braking possible without

BS

modulation.

The ECU wil l cut out the ABS system via the sys

Technical

descr iption

5 27

When the ABS system is inoperative, the brake


35/126

tem relay on detecting a break in the c ircu it to

the valve block, the main valve orwheel sensors.

The ignition must be switched

of f

and the

fault

rectified before the ABS warning light can be ex-

. tinguished and the

ABS system reqctivated. Even

if the faul t has been recti fied, the ABS warning

light

will remain on

if

the ignit ion has

not

been

switched Off.

The ABS system wil l also be inoperative

if

the

level in the fluid reservoir

falls

too low orthe hyd

raulic pressure drops below

105

bar

1523

psi).

In either

case, both the

ABS

warning

light

and the

brake warning light will come on.

Weak signals f rom the wheel sensors wil l a lso

cause operation

of

the ABS system

to be

sus

pended and the ABS warning light

to

come on. In

such cases, when there is no system fault as

such, assoon as the problemhas been

dealt

with

e.g. topping up the f lu id or restoring the hyd

raulic pressure) the system wil l become opera

tive again and the

ABS

warning light will be extin

guished.

system wil l funct ion l ike a convent ional brake

system.

The signals from the wheel sensors are proces

sed

by

the

ECU

which computes;a ir.eference

speed for the vehicle. The indiMidualsignals are

then compared with this reference

Qpeed lf

any

of

the

signals depart from th is referenc:e valve,

the modulating procedure will

be

activated., as

follows:

Phase

Lock-up tendency detected.

System prevents increase in brake pressure.

Phase

Initiation

of ABS

modulation.

Brake pressure reduc-e:d held constan t or in

creased, depending on increase or decrease in

wheel rpm.

Phase

Tendency

for

wheel to lock gone.

Brake pressure increased depending on road

adhesion checked in phase 2.

Saab

500-28 Technical description

l e ~ y ~ l l I s e l l l a H l i l e ~


36/126

The relays and fuses

f or t he

ABS system are

housed in a special fuse panel fitted alongside

the ECU.

The fuse panel contains the system relay, with a

fuse

for the ECU,

a relay and fuse for

the

pump

motor

and an addit ional fuse for

the ECU.

el y

n

fuse p nel

1 Relay, pump motor

2 Relay,

ECU

3 Fuse, ECU

lOA,

ASS

4 Fuse,

ECU

30A,

ASS

5 Fuse, pump motor 30A, Pump

Bli ake WamU[Bg all ld AS S wamnng IDghts

There are three warning

lights

for

the

brake sys-

]

em:

ANT

Q

Handbrake warning light 1

lOCK

G

ABS Anti-lock warning

light

2

o Brake warning

light

3

Or

The handbrake warning is

not

affected by

the

ABSsystem.

PARK

ANTI

R KE

R KE

lOCK

f lUU)

M

3

L

Saab900

Technical description 5 29

IBHrake wialmulI1lg ~ u g l h ~ 081l:


37/126

ANTU

LOCI {

SaabSOO

If both

of

these l ights are on, this indicates that

the level in

the

f lu id reservoir has dropped

further or the pressure in the accumulator has

dropped below 1 5 bar 1523 psi .

The

ABS system will be inoperative

bu t

reduced

braking

effect

wil l remain i.e. g reater pedal

pressu

re

requ ired .

Ifthe

lights have come

on

because of

insufficient

fluid in the reservoir, leakage in one of the cir

cui ts is ind icated . The car mus t not be driven

further until fauit has been found and

rectified.

If the Iights have come on because of a pressure

drop in the system, neither the power assistance

nor the brake pressure to the rearwheels wil l be

in

proportion to pedal pressure. At worst,

if

no

hydraul ic pressure remains, there wil l be

no

power assistance and no rear-wheel braking. The

front-wheel brakes will stil l operate normally but

without power assistance.

lBli ake wamulmg almd AIBS warrrrnolmg ~ u g l h t

bott

on:

The brake warning light alone will come on if the

level

of fluid

in the reservoir drops below the MIN

mark.

The

brakes and ABS systemwill continueto oper

ate normally.

AlaS Wll i II1lUlmg ~ n g l h t

Olm:

The ABS

Anti-lock warning light alone will come

on if the ECU detects a fault in the ABS system.

Conventional braking power will be available but

the ABS system will be inoperative.

;

h e e ~ SelllSOIrS

5 3

Technical description


38/126

.

; ; ; ; ~ t { ; ~ { r

=

The wheel sensorsoperate on the generator pri n

ciple, i .e. a current is induced in a conductor by

distortion

of

the magnetic field surrounding it.

Distortion

of

the magnetic f ield around the sen

sor is caused by the toothed sensor wheel as

it

passes

the

sensor body: each

time

a tooth pas

ses the sensor the magnetic f ield is reinforced.

Each

time

a gap between the teeth passes the

sensor,

the

magnetic field isweakened. Put sim

ply,

this

means

that

positive + current is gener

ated by each tooth and negative - current by

each gap between the teeth.

Thus, alternating current is generated, the fre

quency and amplitude

of

which (

the

number

of

cycles per second and hal f the peak-to-peak

value, respectively) will vary with

the

speed at

which

the

sensor wheel is turning. From

this

sig

nal, the

ECU

can deduce the speed

of

rotation

of

the wheel.

nsorwh l

F 6 O R l t ~ w h e e l

sensor and sensorwheel

Each sensor has a toothed sensor wheel, which

is press-f it ted onto the constant velocity joint.

The sensorwheel cannot

be

removed.

The sensor is mounted vertically on

the

steering

swivel member, i .e. orientated radially

to

the

sensor wheel. The gap between the sensor and

the sensorwheel can beadjusted by means of an

adjusting

s l e e v ~

and setscrew.

The sensor leads can be disconnected

by

means

of

a connector in the engine compartment.

Because

the

sensor is orientated axially relative

to the sensor wheel, the design

of

the rear sen

sor wheels is different to

that of

the

front

ones.

,The sensor wheel is press-f it ted onto

the

rear

wheel hub and cannot be removed.

The sensor leads can be disconnected

by

means

of

connector underneath the rear seat.

Saab900


39/126

5

1

1

S

c

o

n

tr

ol

de

s

cr

ip

ti

o

n

o

f o

p

e

r

ti

o

n


40/126

T

he

b

ra

ke

s

ys

tem

ca

n

be

in

o

ne

o

f th

re

e

co

nd

i

ti o

ns

:

1

Br

ak

es

o

ff

2

B

ra

ke

s

ap

pl i

ed

w

it h

o

u t

S

mo

d

ul a

ti o

n

3

B

ra

ke

s a

pp

lie

d

w

ith

S m

od

u

la t

io n

Hy

dr

au

lic

p

re

ssu

re

is

p

re

se

nt

be

tw

ee

n

th

e a

cc

u

m

u

la t

or

an

d

th

e c

o

nt r

o l

va

lv

e,

ke

ep

in

g

th e

fe

e

d

p

as

sa

ge

b

et

we

en

t

he

ac

cu

m

ul

a to

r

an

d s

er

vo

cy

-

l

in d

e

r c

los

ed

,

an

d

th

e

re t

ur

n

pa

ss

ag

e

be

tw

ee

n

th

e s

erv

o

cy

lin

de

r a

nd

f

lu i

re s

er

vo

ir

op

en

.

Th

e

se

rv

o

cy

lin

de

r,

m

a

st e

r

cy

lin

de

r

an

d

ot

he

r

h

yd

ra

u l

ic

co

mp

o

ne

nt

s a

re

a

ll

ch

arg

ed

w

it

h f

lu

id

t

atm

o

sp

he

ric

p

re

ss

ur e

.

T

he

i

nle

t a

nd

o

ut l

e t

va

lv

es

in

th

e

val

ve

b

lo c

k

an

d

th

e m

a

in

va

lve

a

re

a

ll i

n

th

e r

es

t

de

-en

e

rg i

ze

d

po

si t

io

n.

Saa

b

control description of oper tion 5 1 2


41/126

i

Accumulator pressure

Atmospheric pressure

r kes

2 Accumulator

3 Pump delivery pipeconnection

4 Control valve

5 Lever mechanism

6 Actuating plunger

7 Servo plunger

8 Rear brake

circuit

9 Front brake circuits

1

Inlet valve in valve block)

11 Outlet valve in valve block)

12

Brake caliper

Saab9

5 1 3

control description of oper tion

IBrralkes a j p I P ~ e d woi holUlt ArBS m o d ~ a t i o n


42/126

When t brake pedal is applied and there is

no

tendency for any wheel to lock, the control valve

admits hydraulic pressure from the accumulator

proportional

to

the pedal pressure.

The pressure

in

the servo cylinder acts

on

the

servo plunger and reinforces the braking force

transmitted to the rearwheels. The servo plunger

acts

on

the tandem plunger, which closes the

central valves, causing pressure to rise

in

the

front-wheel circuits. Hydraulic pressure to the

wheel cylinders is transmitted through the valve

block, in which the inlet and outlet valves are in

the rest de-energized position.

Saab

control description of oper tion 5 1 4


43/126

=:


Mastercylinder pressure servo pressure


r kes pplie without S modul tion

2 Accumulator

3 Pump delivery pipeconnection

4 Control valve

5 Lever mechanism

6 Actuating plunger

7 Servo plunger

8 Rear brake circuit


10 Inletvalve in valve block

11 Outletvalve in valve block

12 Brake caliper

Saab

501 5

SS

control: description of operation

[Bll akes

a l l ~ e d

wfittlh

SSmodulation

SSmodulation is initiated when the system de


44/126

tects a tendency for a wheel

to

lock.

s

soon as

the ECU detects from the inpu t s igna ls a ten

dency

for

a wheel to lock,

it

closes the

inlet

valve

for the c ircu it in quest ion. At the same

time

as

the main valve opens, the brake pressure is re

duced as the

outlet

valve for the circuit opens.

When SSmodulat ion is ini tiated, all braking is

effected by accumulator pressure provided via

the control valve inthe servo cylinder. Thus, both

front-wheel circuits will

be

isolated from sta

tic

pressure present in f ront

the

tandem

plunger seals. The circuits are insteadSUbject to

dynamic pressure, caused by t he brake f lu id

being fo rced past the seals to t he chamber

beyond, and thence

to

the valve block in which

the pressure modulation takes place. The

dynamic pressure also acts on the positioning

sleeve, providing a nonpulsat ing reserve

of

pedal travel.

The pressure in the respective circuits is depen

dent

on the

retardation inwheel speed sensed

by

the sensors. The ECU controls the inlet and out

let valves so thatmaximum braking force coeffi

cient of adhesion is maintained between the

wheel and road sur face occurr ing at approx.

20

slip .

ASS-modulated braking will continue until:

the car has brought

to

a standstill

o the force applied by the driver

t o t he

brake

pedal has been reduced to the level

at

which

there is

no

danger

of

the wheels locking de

termined

by

the relationship between braking

force and the coefficient

of

adhesion .

Note

that

the pressure in the circuits can never

exceed

the

pressure applied to the brake pedal

by the driver.

The brake fluid returned to the reservoir via the

outlet valves is replaced

by

f luid from

the

ac

cumulator. The capacity

of

the accumulator is

sufficient

to

ensure

that

the required quantity

of

pressurized brake fluid will always be available

during ASS-modulated braking.

Saab900

SS control: description of operation

501-6


45/126

t ~ ~ : t ~

L


Master cylinder pressure servo pressure


rakes appliedwith Smodulation

2 Accumulator

3

ump

delivery pipeconnection

4 Control valve

5 Lever mechanism

6 Actuating plunger

7 Servo plunger

8 Rear brake circuit


10 Inlet

valve

in

valve

block

11 Outlet valve in valve block

12 Brake caliper

Saab900

..

J

D

J


46/126

omponent removal fitting

51 1


47/126

51 2

51 23

51 26

51 27

Pump and motor

unit

Valve block

U

Wheel sensors

51

51

51 12

51 13

51 15

o r mov

Brake fluid reservoir

Hydraulic unit

~ c c u m u l t o r

P ressure switch

Pump delivery pipe

Saab9

1 Remove the

ir

intake

2 Remove the retaining

bolt

forthe coolant ex-

pansion tank and move the tank out of

the

way

51 2


3 Siphon of f the f luid from the reservoir. Note

that itwil l notbe possibleto

emptythe

reser-

voir completely.


48/126

4 Unplug the electrical connector

for

the f luid

level indicator

onthe

reservoir.

Manuals only: Disconnect the hose for the

clutch cylinder and plug the end.

Take care not

to

lose any fluid from the hose.

.

ffluid is lost air may get into the clutch hyd-

raulics

6 Undo the reservoir retaining screw.

~ ~ ~ f . f ; ~ ~ ~ ~ l f t ~ ~ t ~ ~ : ~ ~ ~ ~ i f ~ ~ : : : ; 2 ' ~ ~ ~ ' ~ J o 2 ~ : ' S ( ; ~ ~ : : : , ' . ~ : . '

.

....

;.

.

Saab


51 3

Lift the reservoir

of f

the hydraulic unit y

withdrawing

it

from the rubber bushes

Take care not to lose the spacer

nd

ring


49/126

Saab9

8 Disconnectthe pump feed hose from the re-

servoir

on

the rear connection

9 Remove the rubber bushes from the hyd

raulic unit

51 4

Component remova l/ fi tt ing

1

f

it

1

F

it t

wo

n

ew

r

ub

be

r

bu

sh

es

in

t

he

h

yd

ra

ul i

c

un

it .


50/126

2

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ed

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os

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o_

the

r

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r.

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.

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sp

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; I

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it.

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gh

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.

5

Ma

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ly

: R

e

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th

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as

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om

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ihd

ic

ato

r.

7

Mo

ve

th

e

c

oo

la

nt

ex

pa

ns

io

n

tan

k

ba

ck

in

to

pl ace and t igh te n the bol t.

8

R

ef

it t

he

air

in

ta

ke

.

9

F

iW

th

er

es

er

vo

ir w

it

h

DO

T

4 b

ra

ke

fl

u id

.

1

B

le

e

d

th

e b

ra

ke

s

ys

tem

.

F

or d

et

ai

ls

re

fer t

o

s

ec

ti o

n

5

2

1

1

S

w

itc

h

on

th

e

ign

it

ion

a

nd

w

at

ch

to

se

e t

ha

t

the

b

ra

ke

a

nd

A

SS

(A

n

ti-l

oc

k)

w

arn

in

g

lig

h ts

g

o

of

f.

1

2

Te

st

dr

ive

t

he

c

ar

an

d

ve

rif

y t

ha

t

the

b

ra

ke

sy stem is working prop er ly .

S

aa

b9

Component removal/fitting

51 5


51/126

10ll emmfe

1 Remove

the

centre console

2 Remove t he padded t ri m pane l f ro m be lo w

the

dash

Saab9

51 6


3 Remove the heater duct

i


52/126

4 Remove the acoustic insulation from behind

th pedal assembly

5 Disconnect th defroster hose from tt \e

heater box

6 Remove t he p in r et ai ni ng c li p and w it hd ra w

th pin from th hydraulic

unit

pushrod

7 Remove t he

ir

intake

Saab

I


51 7

Remove the retaining olt

forth

coolant ex-

pansion tank and move the tank out

of

the

w y


53/126

Saab

9 Unplug all e lect ri ca l connectors from the

hydraulic unit:

o

pressure switch 1

main valve 2

o fluid level indicator 3

pump motor 4

51 8


1 Unbol t the bracket between the hydraul ic

unit

and

front

assembly. Disconnect the

earth lead and unplug the connector

for the

sensor lead. Move

the

bracket and electrical


54/126

leads out of

the

way.

11 Siphon off

the fluid

from the reservoir. Note

that it will

not

be

possibleto

empty the reser-

voir completely.

12 Manuals only: Unplugthe hose

for

the clutch

cylinder and plug

the

end.

Take care notto lose anyfluid from the hose.

Iffluid is lost

air

may get into

the

clutch hyd-

raulics.

13

Label the brake pipes and the large bore re-

turn pipe.

14 Disconnect the brake pipes and large bore

return

pipe together to avoid putt ing ten-

sion on the pipes.

Plugthe ends ofthe pipes and

the

openings

in

the

hydraulic

unit

and valve block.

15 Undo the four securing nuts forthe hydraulic

unit the

bulkhead behind the pedal as-

sembly.

16

Lift out

the hydraulic unit.

Saab9

Component removal/fitting 510-9


55/126

Noie

On f it ti ng

t he hydraulic uni t, i t i s easy for the

stop-I ight switch and cruise-control switch i f

: any

to

be pushed inadvertently. If so, use a

: pai r

of

pliers to reset them.

,

.

1 : _ .

,

1 Offer up the hydraulic

unit

and ensure

that

t he pushrod is co rrect ly a li gned with the

pedal assembly.

2 Reconnect the pushrod,

fitting the

pin and

pin retaining clip.

3 Tighten the hydraul ic

unit

retaining nuts o

the bulkhead behind the pedal assembly.

Tightening torque:

26

4 Nm

19

3

Ibf

f

4 Connect the brake pipes and large-bore re

turn pipe.

Saab900

51 1


Manuals only: Reconnect

th

clutch feed

hose to the reservoir Make sure th t fluid

has not been lost from the hose


56/126

6 Plug the sensor lead connector and

fi t

the

bracket between the hydraulic unitand front

assembly Remember to secure the earth

lead the top bolt

Saab 9


51 11

7 Reconnect all the electrical leads:

pressure switch 1)

main valve 2)


57/126

Saab9

fluid level indicator

3

pump motor

4

8

Move the coolant expansion tank back into

place and tighten the bolt.

9

Refit the

air

intake.

,

1

Fill the reservoir with

DOT

4 brake fluid.

11

Switch

on

the ign it ion and check

tha t the

pump is working.

12

Bleed the brake system.

For detai ls refer to section 520.

13

Inspectthe brake system for leaks and check

that the brake and ABS Anti-lock) warning

lights go

off

14

Reconnect the

LH

defroster hose.

15

Fit the acoustic insulat ion behind the pedal

assembly.

16

Refit the heater duct.

17

Refit the padded trim panel underthe dash.

18

Refit the centre console.

19

Test drive the car and verify

that

the brakes

and clutch are working properly.

510-12



58/126

Yo

remove

1 Removethe accumulator 8-mm Allen key .

Yo tnt

1 Fit a new

0

ring

on

the accumulator.

2 Fit the accumulator.

Tighfl:eningtorql,le: 3446 Nm

25

-

341bf

ft

3 Switch

o n ~ h e

ignition and watch

to

see

that

the

r k ~ n d

S

Anti-lock warning lights

go off.

4 Test drive the car and verify

tha t the

brake

system is working properly.

r

Saab900


51 13


59/126

Saab

9

: ; : ~ ~ ~ : d :

:--

3 Fit special tool

8996571

and unscrew the

switch

1 Remove the rubber damper f rom the pump

delivery pipe

2 Unplug the e lec tr ical connecto r from the

pressure switch

To emove

H i n ~

Ifthe

switch is

difficultto

und insert a suitable

brace between the pump body and the hydraulic

unit

b

lO

4

Component removal/f it t in g

1

Fi t

a

ne

w

0

r

ing

a

nd

s

cr

ew

in

th

e

p

res

su

re

sw

itc

h.

T

ig

ht

en

in

g t

or q

u

e:

20

-

26

N

m

1

5


60/126

-

1

9

I

bf

ft

2

u

g t

he

co

n

ne

ct o

r

on

to th

e

p

re

ss

ur

e s

w

itc

h .

.

3

F

it t

he

ru

bb

er

da

m

pe

r o

n

to

th e

p

um

p

de

l i

ve

ry

pipe.

4

S

wi t

ch o

n

t

he

ig

n

it io

n

an

d

wa

tc

h t

o

se

e

th

a

t

t

he

b

rak

e

an

d

A

nt i

-lo

ck

w

a

rn

ing

li

gh

ts

go

of

f.

5

I

ns

pe

ct

th e

b

ra

ke

s

ys

tem

f

or

6

T

es

t d

riv

e

th

e c

a

r a

nd

v

er

ify th

at

th

e

br

ak

e

s

ys

tem

i

s w

o

rk

ing

p

ro

pe

rly

.

S

aa

b9

00


510 15

.


61/126

Saab900

2 Remove the retainingbolt for the coolant ex-


of

the

way

3 SiphQ:t1offthe flufd from the reservoir Note

that itwil l

not bep0ssibl:e

t o

emptythe reser-

voi r completely

To Il emove

1 Remove the air intake

51 16

Component removal fitting

4 Unplug the electrical connector for the fluid

level

indicator on the reservoir


62/126

Saab PO

5 Manuals only: Disconnect the hose for the

clutch cylinder and plug the end

Take care notto lose anyfluid from the hose

Iffluid

is lost air may

get

into the clutch hyd-

raulics

6 Undo the reservoir retaining screw

T Lift

the

reservoir

off

the hydraulic

unit y

withdrawing

it

from the rubber bushes

Take care not to losethe spacer and ring

on the rear connection

Plug the holes in the rubber bushes n the

hydraulic unit

ompon nt

removal fitting

51 17

8 Disconnect the rear brake pipe

on

the hyd-

raulic unit to gain betteraccess tothe pump

delivery pipe coupling

Plug the end

ofthe

brake pipe

n

the open-

ing

in

the hydraulic unit


63/126

Saab

9 Remove the pump delivery pipe

Plug the two openings for the pipe

in

the

unit

51 18 omponent removalfitting

it

F

it

t

h p

um

p

d

eli

ve

ry

pip

e


64/126

2

R

ec

on

ne

c

t

th

re

ar

br

ak

e p

ip

e

Saa

b


510 19

,

1

3 Slide the spacer and 0 ring onto the reser-

tj voir rear connection. Install the reservoir

by

pushing the connect ions in to the rubber

bushes in the hydraulic unit.


65/126

4 Tighten the reservoir retaining screw.

5 Manuals only: Reconnect the c lutch feed

hose

to

the reservoir. Make sure

that

fluid

has

not

been lostfrom the hose.

6 Plug the elect rica l connector onto the f lu id

level indicator.

7 Move the coolant expansion tank back into

place and tighten

th e

bolt.

8 Ref it the air intake.

9 Fi ll the reservoir with DOT brake fluid.

10


For details refer to section 520.

11

Switch

on

the ignition and watch

to

see

that

the brake and

BS

Anti-lock warning lights

go off.

12

Test drive the car and ver ify

that

the brake


F

,

i

r

;

r ;

i

Saab900

51 2


The pump and motor

unit

cannotbe removed with

the

hydraulic unit

the car


66/126

Unt

It

i s a good idea

to

remove the a ccumulator be-

fore the hydraulic

unit

is removed from the car

Plugthe opening in the pump body

1 Disconnectthe pump delivery pipe from the

pump unit

Plug the open end

of

the pipe

2 Prise back the catch and unplugthe elect ri -

cal connector

3 Disconnect the

inlet

hose from the pump

unit

Saab9


51 21

Undo the securing screw at the front of the

pump unit


67/126

Saab

. . ( : \ ; : ~ ~ . ~ j

Note the order for reassembl ing the dam-

pers washers and spacer

Hint

If

the switch is

difficultto

und

inserta suit-

able brace between the pump body and the

hydraulic unit

5 Disengage the pump and motor

unit

from its

rear mounting

6 Remove the pressure switch

s

special tool 899657

51

0

-

2

2

C

o

m

p

on

e

n

t remova l/f it t ing

T

o

fi

t

1

F

it

a

ne

w

0

ri

ng

a

nd

sc

re

w

in

th

e

pr

es

su

re

sw

it

ch

.

T i

gh

te

ni n

g

to

rq

ue

: .

2

0

-

2

6 \

\ m

15

- 1

9

Ib

f f

t


68/126

2

R

ec

on

ne

ct

th

e

in

le

t ho

se

to

t

he

p

um

p

un

it.

3

En

g

ag

e t

he

re

ar

m

ou

nt

in g

o

n

the

p

um

p

un

it .

4

As

se

m

ble

t

he

da

m

pe

rs

, w

as

he

rs

a

nd

sp

a

ce

r

a

s s

ho

w

n

an

d

fit

th

e s

e

cu

rin

g

bo

lt .

5

P

lug

the

e

le

ctr

ic a

l

co

nn

ec

to

r.

6

R

ec

on

ne

ct

th

e

p

um

p

de

liv

e

ry

pi

pe

to

th

e

pu

m

p

un

it .

Refi t th e hy dr au lic uni t in th e ca

r.

Fi

t th

e

ac

cu

m

ul

a to

r.

T ig

h

ten

in

g

tor

qu

e:

34

- 4

6

m

2

5 -

34

Ib

f

fa

Sa

ab


51 23


69/126

remove

Remove the air intake

2

mov

the retaining

boltforthe

coolant

x-


of

the

way

3 Siphon

of f

the

fluid

from

the

reservoir Note

that itwill notbe possible to empty the reser-

voir completely

4 Unplugthe electrical connector

on

the valve

block

Saab9

5 Disconnect the brake pipes from the under-

side of the valve block:

1 front left nearest wing

2 rear middle

3 front right nearest engine

51 24



70/126

Saab

nt

To

stop brake fluid escaping, raise the ends

ofthe

pipes and

lightlytightell

downtIle con-

nections to the hydraulic unit.

Plug the ends of the brake pipes and return

pipe, and the openings in the valve block.

Hint

Place a rag under the valve block connec-

tions

to prevent brake fluid gett ing onto the

paintwork.

Undo the nut on the cover underneath the

pipes.

Slacken off the connections at the hydraulic

unitto

avoid stressing the pipes.

7 Withdraw the brake pipes and return pipe

from the valve block.

6 Disconnect the brake pipes and the large-

bore return pipe from the valve block.

8 Snipthrough thetie securingthe wiring loom

to the valve block.

9 Remove the three nuts and lift of f the valve

block.

I


510 25

lome

1 Lift the valve block into posit ion and tighten

the three nuts.


71/126

2 Reconnect the brake pipes to the underside

of

the

valve block:

o 1) front left nearest wing)

o 2) rear middle)

o 3) front right nearest engine)

Secure the wiring loom to the valve block by

means of a cable tie.

4

Slacken off the connections

atthe

hydrau Iic

unit.

Connect the brake pipes and return pipe to

the valve block. Tighten the

fittings

:>i

Fitthe cover forthe underside of

the

pipes to

,

the

wing.

5

Plug on the connectorfor the valve block.

6

Move the coolant expansion

tank

back into

place and tighten the bolt.

7

Refit the air intake.

8

Fill

the

reservoir with DOT 4 brake fluid.

9


For details refer to section

520

10

Inspect the brake system for leaks. Switch

on the ignition and check that the brake and

S Anti-lock) warning lights go off.

11

Test drive

the

car and verify that the brake


Saab900

L

510:-26 Component removal/fitting

Note

The

U

must

not

be exposed

to

hi gh tempera

tures. Always remove

it

from the carbefore start


72/126

ing any arc welding stove drying etc.

Il emove

1 Unscrew the

U

from the

LH

wing insidethe

engine bay.

2 Lift up the U module and unplug the con

nector.

1 Plugthe connector onto the module.

2 Screw th e

U

module into place.

Saab

lTemove

flr n ft

Q

wll ee Sell1lS0ffS


51 27


73/126

Saab

9

1 Unplug the sensor lead connector one fo r

each wheel inside the,.engine bay by push-

ing the halves together and twisting

bayonet fitting .

2 Raise the

front of the car and remove the

road wheel.

3 Withdrawthesensorlead fromthe

gu

ide and

pull it through the rubber grommet in the

wheel arch.

510 28

Component remova

I fitting

4 Undo the screw and remove the sensor.


74/126

Saab9QO

Note the plast ic sleeve that is

fitted

to pre-

vent corrosion between the steering swivel

member and the sensor.

rRea mwheei senSO[fS

1 Unplug the sensor lead connector one for

each rear wheel located under the rear seat

by pushing the halves together and

twisting

bayonet fitting .

2 Raise the car and remove the road wheel.

3 Pull the sensor lead through the rubber

grommet in the floor.


51 29

Undo the clip securing the handbrake cable

to

th suspension arm

Note the position o the distance piece


75/126

Saab

5 Release the sensor lead from the guide

th back

o

the suspension arm

6 Undothe screw and remove the sensor

510 30


The following items

must

be carried out before

the

new wheel sensor

is f i tted.

Note

o secure the sensor inthe vice grip the adjust

ing sleeve

in

the jaws. Never clamp the sensor

body

itself

as

this

can

distort

it.

0

:


76/126

Undo the setscrew and transfer the adjusting

. sleeve

to

t he new sensor. Check

that

the

sleeve slides freely: if necessary polish the

surface with a piece

offine

emery cloth. Clean

the surface thoroughly and lubricate l ight ly

before

fitting

the sleeve.

G

se

a wire brush

to

remove all tracesofthe old

fibre spacer from

the

end

ofthe

sensor. Clean

the

surface with a rag

i f

required moistened

with a

little

petrol/gasoline .

o Remove any traces

of f ibre or dir t

from inside

the

sensor housing. Spin the sensor wheel

slowly and remove any

fibre

remains or d ir t

from between the teeth. At

the

same time in

spect

for

signs of damage.

Glue a new f ib re spacer onto the end of the

sensor.

Spacer thickness:

0.65

mm

Note

Once

the

sensor with

the

new fibre spacer has

been pushed out towards the sensor wheel the

road-wheel hub must

not

be rotated before the

sensor has been secured in

its

correct position.

If

the hub is rotated premature ly the sensor

wheel will

tearthe

spacer causing the sensorto

be

set

incorrectly. Offset the adjusting sleeve

half-a-turn to bring the setscrew

to

a new posi

tion.

Saab900


51 31

fvoll1ft

g

wheeD

se11lS0B S

Fit the sensor tightening the retaini[lg

screw.


77/126

;

.

Saab

2 Press the sensor body gent ly aga inst the

sensor wheel and tighten the setscrew.

3 Insertthe sensor lead through the grommet

in the wheel arch and secure it

in the guide.

4 Reconnect the sensor lead connector inside

the engine compartment.

5 Fit the road wheel.

After fitting ensure

th t

the sensor lead

cannot chafe againstany

of

the components

when the wheel is at ful l lock.

I

51 32


l e a l l i m w ~ e e ~

seIrilSO S

1 Fit the sensor t ig ht eni ng th e retaining

screw

;


78/126

Saab

2 Press the sensor body gently aga inst the

sensorwheel and tighten the setscrew

3 Fit t he

cl ip for the handbrake cable onto the

suspension arm

Note the position

o

the distance piece

4 Insert the sensor lead through the grommet

in the f loor and secure t to the suspension

arm

5 Reconnect the sensor lead connector under

the rear seat

6 Fi t the road wheel

Bleeding the brake

syst

52 1

~ o t

L;

The front wheel brakecircuits mustbe bled first.


79/126

Saab

3 Have a helpe r depress the brake pedal as

you

undo the nipple.

With the pedal down to the floor tighten the

nipple and then release the pedal.

Repeat this operation until no ir bubbles

are visible

in

the hose.

Repeat s teps 2 and 3 to bleed the

circuit

for the

front wheel.

f required a bleeder unit can be used for

the

.

front brake circuits.

1 Top up as necessary with

DOT

4 brake fluid.

2 Connect a length of transparent hose to the

bleed nipple on the

R

front brake caliper.

Place

the

other end of the hose in a suitable

receptacle.

52 2

Bleeding

the

brake system

Note

The front wheel brake circuits mustbe bled first.

1 Top upthe reservoir as required with

OT

4

rl


80/126

brake fluid.

2 Connect a length of t ransparent hose to the

bleed nipple

on

one

of

the rear brake cal ip-

ers. Place the otherend of the hose in a suit-

able receptacle.

3 Have a helperswi tch on the ignit ion and de-

press the brake pedal.

4 Undo th e brake nipple and draw

of f

brake

fluid

until no bubblesarevisible inthe tube.

To bleed the remainder

of

the c ircu it to the

other wheel repeat steps 2 3 and 4.

5 Top up the brakef lu id

to

bring the level up to

the

M X mark on the side

of

the reservoir.

Saab9

Changing the brake fluid

530-1

All brake fluid deteriorates

after

a

time

through

i i oxidation and absorption of water. This lowers

t: ~ t h e

boiling pointof the fluid, which maytherefore

> . vaporize during prolonged hard braking. The re-

r

f


81/126

; C S H l J I ~ i O i 1

To

avoid possible brake failure, all old brake fluid

must be drained from the system. The fluid

capacity

of the

brake system is approx.

1.2

litre

i

1.3

l iq qt).

sult

can be sudden brake failure. It is therefore

essential that the brake fluid is changed regu-

larly at the specified intervals (see the Mainte-

nance Programme in Section 1:2 of the Service

Manual).

If requi red, a bleeder uni t can be used for the

front brake circuits.

1 Siphon of f the fluid from the reservoir. Note

that itwill be notbe possibleto emptythe re-

servoir completely.

2

Top

up with

OT

4 brake fluid.

3 Connecta length of transparent hose to the

bleed nipple on the

RH

front brake caliper.

Place the other end of the hose in a measur-

ing cylinder or other graduated receptacle.

4 Have a helpe r depress the brake pedal as

you

undo the nipple.

With the pedal down to the floor, t ighten the

nipple and then release the pedal.

Repeat the procedure until approx. 0.5litres

(0.5 l iq qt) has been drained off.

To drain the circuit forthe LH front wheel: repeat

s teps 3 4, except this

time

drain of f approx.

0.1

litre

0.1Iiqqt)

offluid.,

Saab900

530 2

Changing the brake fluid

Connect a length

of

transparent hose to the

bleed nipple

on

one

of

the rear brake calip-

ers Place the other end

ofthe

hose in a suit-

able receptacle


82/126

6 Have a helperswi tch on the ignition and de-

pressothre brake pedal

7 Openthe bleed nipple until approx

0.1

litre

O l l i q q t ~ o f fluid has been drained off

..

Repeat steps 5 6 and 7 to drain the

remainderof

the

circuit to the other wheel

8 Fill up wi th brakef lu id

to

bringthe level up to

the X mark on the side

ofthe

reservoir

Saab900

r

ASS-system tester 590- 1

.590 15

5 .9 0- 16

5 .9 0- 18

:5 90 22

590 26

Selecting the ABS-system version

Test mode

Valve

test

mode

Monitor mode .

Error codes: ,

. 590 1

, 590 2

590

8

590 11

590 13

Technical d ata , . , . . .

;Technical description . . .

Quick checks _.

; Connecting the

tester

to the car

..Connecting the pressure sensor


83/126

The casing of t he t es te r u ni t

is

made

of impact

and o il -r es is ta nt p la st ic and in corpo rate s a

hinged cover over

the

display and control panel.

r n S ~ a y .

Specially designed

LCD

display having

56

seg

ments.

590 27

Fault-diagnosisrouti,nes

590 14

Checking

the accumulator

., gas pressure . . . . .

Special oil-resistant design incorporating three

membrane switches.

Mncmpll Ocessoll

Eight-bit sin gle-chip microprocessor with

analogue/digital converter and 4 K internal stor

age.

lP oweil

COB11SMmlPtnOIl11

Approx. 17 0

m A in

ready mode.

Connection between the

ECU

and the car s wiring

loom is made using a two-way male/female)

35

.

f.

pin connector. :

The power supply

for

t he t es te r is t ak en d ir ec t

f ro m t he b at te ry vi a a lead f it te d w it h c ro co di le

clips.

A pressure sensor can

be

connected to the

ABS

accumulator

for

measuring hydraulic pressure.

Saab

900

59 2

SS system tester

t G e 6 i l e R a ~

The SaabASS-system tester has been developed

for efficient servicing and fault-diagnosis work

on the Saab

braking system.

The equipment comprises the following compo

.

. ~ ; ~ - . :

The

tester

can be usedfbdhr.ee

different

sets

of

tests : ~ . : : . .

a Automatic testing

of

eacti-Wheel sensor and

lead, and

of

the hydraulic pressure in the sys-


84/126

nents:

Tester

o

Test lead with a two-way 35-pin connector

Power supply lead

Pressure sensor with connecting lead

tem Test Mode .

b Manual valve testing ValveTest Mode

c Manual

tes ting of

each wheel sensor and

lead, and

of

the hydraulic pressure in the

brake system Monitor Mode

BS system t st

1 Testerunit

2 Test lead with two-way 5 pin connector

3 Power supply lead

4 Pressure sensorwith connecting lead

5 Port for power supply

6 Port fo r test lead

7 Portfor pressure-sensor lead

Saab9

of

l

s-

Test prompts

Measured values and error codes, with over

view

of test

items

Valve

and

ABS-version monitor

BS system tester

59 3


85/126

1d

e

,

1-

. .

This part

of

the display shows instantaneous val

ues for wheel speed, wheel sensor signal

amp li tude, sensor-wheel eccen tric it y - and

which wheel the values refer to.

A check is a lso made of the relays, and

of

ac

cumulator pressure ifthe pressure sensor is con

nected. Error codes are displayed at the end

of

the run.

The valves operating during the test are indi

cated

as

is the ABS-system version selected.

, Displaysdriving instructions

forthe

operatordur

, ing testing.

(Details

of

individual prompts are given

on

page

590 5.

,

.

t

} .

l

r

{ .

j

t

f

0

j

Saab9

590-4

ASS-system tester

ITimI

IGNITION

I

IGNITION

OFF

DRIVE)20 Km/h APPLY BRAKE

I STOP CAR

STRIKE RElEASE BRAKE I

SYSTEM OK


86/126

Saab900

c

rq

t

lo

a RR

Ilm/h

~ r n r n t m ~ o o ABS-TYPE

v { {

h h R R

1 2 3 4

t

START

TEST

Function

(1) (1)

0.

01

NEXT

> t::

ERROR

E < l

u

CODE

4>

Function

Al:>

ABS-System

tester 1

89965 4

Brakes

V

-

n

There are three buttons of the membrane-switch

type

on

the control panel:

Button A is used to start the test cycle and to run

through the error codes.

Button B is used

to selectthe

program

that

mea

sures wheel-sensorsignal strength, tests the op

eration

of

the wheel sensors and measures ac

cumulator pressure if pressure sensor con

nected) .

Button C is used to select the program that mea

sures sensor wheel eccentricity, to testthe oper

ation of the wheel sensors and to measure ac

c umul ator pr es sure ( if pr ess ur e s ensor con

nected).

Buttons Band C can be depressed simultane

ously to select the ABS-system version.

A

ASS-system tester

59 5

lmll

IGNITION ON

I

IGNITION OFf

DRIVE)20 m/h I APPlV BRAKE I STOP CAR

Dill

STRIKE

RelEASE BRAKE ISYSTEM OK

= =

=

=

PRESSURE

U

UFLBFR

O o R

RR

Note

The test prompts do not appear in the order

shown

on

the display butvarywith

th e test

being

run.


87/126

.

m/h

~ r n r n n J I T l W [ I D

S ~ T V P E

[ ~ ~ R R 3 ~

~

Turn the ignition key

to

the drive position

The program startsthe test

u ESu

IF

brake pedal pulsates

or

pedal travel is greater

than normal: switch of f ignition within

1

sec

onds.

If the pedal nei ther pulsates nor s inks to the

floor, leave the ignition on and

wait

2 seconds

for the next prompt.

\

t

t

I

.

.

i i

lQ RUVlE > 2

km h

Drive the car at a speed greaterthan 2 km/h 13

mph)

but

less than

3

km/h 19 mph)

AIPPIL

Y IBIRAKIE

Press down hard

on

the brakepedal immediately

Take your foot off the accelerator and let the car

coast. Light braking using handbrake only is per

missible.

Foot

of f

brake. No braking permissible

Test completed:

no

fault

found.

Saab9

5 ~ ~ . 6

S ~ s y s t e m

t st

~ g l l ] ~ i j v a ~ u e s ertrtorr odes

Ihstantaneous values

for

wheel speed, wheel

sen$or signal ampli tude, sensor wheel out-of

r,ou, d.and, if the pressure sensor is connected,

hydraulic pressure in the accumulator are shown

on the display, Also shown on

the

display are the

words

ERROR

O E followed by the al

phanumeric code forthe

f ult

detected,


88/126

Hydraulic pressure in the accumulator

f

Front Right wheel

L

Front Left wheel

R L

,

l

Rear Left wheel

Rear Right wheel

Saab

ABS system tester

59

7

. ; . _ : : . . . _

M

V

Main Valve


89/126

fF

l

Inlet Front Left left

ront inl t

valve)

Outlet Front Left left

ront

outlet valve)

Inlet Front Right right ront inl t valve)

o

R

Outlet Front Right right

ront

outlet valve)

Inlet Rear rear

inl t

valve)

Outlet Rear rear

outl t

valve)

34

Indicates the ASS-system version selected

Saab

Althou.gh;tMe ABS-system

testeris

the

most

im

portantfault.,.diagnosis aid availabt,e_forthe

ABS

s ys te m, a lw ay s p er fo rm t he fo llow ing_ q ui ck

chec.ksb efo_re.connecting the tester.

IBrake fhdd leveD

59 8

ABS-system tester


90/126

Saab900

el y n fuse

p nel

1 Relay, p um p motor

2 Relay, ECU

3 Fuse,

ECU

10

A

ABS

4 Fuse,

ECU

30A

ABS

5 Fuse, p ump motor 30A Pump

r r r s p ~ t all

the

fuses in thefuse panel adjacent

to

the

ABS-system

ECU.

IFMses

The

fluid

level in the reservoir must be checked

with

the

accumulator fully charged with f luid.

Switch on the ignit ion and check the fluid level

after

the

hydraulic pump has cut out.

Top up, as necessary, with DOT 4 brake

f lu id to

bring

the

level up

to

the X mark on the side

of

the reservoir.

ASS-system

tester 59 9

8,6

0

;

0

:

85

,

I

~ e n i i l l

Check thatthe relay

for

the

ECU

and the relay for

the

pump motor have been fitted correctly.


91/126

87a

c::::J

83 1

el y

orpu p otor

86 Voltage via fuse. 10 A BS

85 Earth via pressure switch accumulator pressure

4 bar

87 Output

to

pump and

ECU

pin 32

3 Voltage via fuse 30APump

I

87

3

I

el y or

U

3 Output to

ECU

pins 3 and 2

85

Earth

87a Earth

87 Voltage via fuse 30A

SS

86 Output

to

ECU pin 8

Saab9

\

59 1

SS system tester

Check l l electrical connections:

Pressure switch

Mastervalve

\ Fluid level indicator switch o reservoir

Electric motor for pump

Connector o valve block


92/126

Also check t t the sensor lead connectors

are making good contact:

Both connectors in engine compartment

J

Both connectors under rear seat

IEali hlBlrog f l o i l ~ s

Check all earthing points:

wheel arch

o

On bracket between hydraulic unit and front

assembly

~ a a b

SS system

t st

59 11

.

Secure

the

connector

by

fi1Jing

a

strap roLjr d

Switch of f

the

ignition.

2 Remove

the ECU

3 Connect

the

tester lead the>ECU

and the ABS wiring loom by means of.

the

two-way

35 pin

connector.. .


93/126

LO

0

the

ECU and connectors.

Run

the test lead down between

the

wheel arch and Apil lar and then into

the

car

via the bottom corner of the door opening.

Connect

the

lead

to

the tester.

Saab9

59 12

SS system tester

4 Connect the powersupply lead

to

the battery

negative terminal first).

Run

the lead through the opening in the

R

A

pillar

and connect

it to

the tester.


94/126

Note

Ensure that the connector is instal led

the

right

way round. Ifthe connector is

fitted

upside down,

the

tester wi

be seriously damaged.

Thetesterwill

nowautomatically selectABS-type

1.

Saab

: - ~ @ O i l [ l i ) < e ~ ~ O l l i ] g

[QHi teMIr rro

: ; @[f

. ; ~ I t is not necessary to connect the pressure sen

~ s o r un lessa pressure-related fault issuspected.

. . '\.

ABS-system tester 590 13


95/126

1 Pressure sensor

2 Fitting with groove f or 0 ring

3 Washer

4 Sleeve

5 '0 ' r ing

Tightening torque:

34

46 Nm (25

34 ib1

ft)

Saab900

5 Connect the pressure sensor lead to thetes

ter.

To disconnect the pressure sensor, reverse

the

procedure for connecting it.

VI >

cJ lrmsd

ftlh jpfi'SSllIJ[fe sell1lJ fi

1 Remove the accumulator.

2 Connect hose

8996597 to

the connection

for the accumulator on the hydraulic unit.

3 Connect th e pressure sensorto the hose.

4 Connect the accumulator to the pressure

sensor.

I

l

59 14 ASS-system tester

thee

~ l i 1 1 g ~ l l

l U J ~ a f t Q r r

gas

Ifess

Connect the tester and pressure sensor as de

tailed on pages 59 11 and 590-13.

1 Set the testerso that

PR SSUR

is shown on

the display.

2 Switch on the ignit ion

and

let the pump

run

until the

SS

Anti-lock warning light goes

off.


96/126

3 Switch off the ignition.

4

Pump

the brake pedal

and

watch the display

on

the tester.

ach

timethe pedal is dessed,

the hydraulic pressure

in

the brake system

drops.

The moment the hydraulic pressure has fal

len to the same level as the gas pressure

in

the accumulator, the value 0 will appear

on

the display.

Note the value shown

on

the display im

mediately before the 0 value appears. This

value denotes the gas pressure in the ac

cumulator bar .

The gas pressure in the accumulator should

be

between

4

and 8 bar.

Saab9

SS systemt st 59 15

e ~ e < c f r D U i 1 g

U - U t = ~ ' Y ~ < e m

W ~ W c

s

s soon as the tester is powered up, it automati

cally s e l e c t ~ B S t y p e 1. This isthe system ver

. s ian wi th a 94-tooth sensor wheel, f it ted to al l

. 989 and earlier models.

The letter t (teeth) is shown on the display

followed

by

thefigure 94 , indicating the number

of teeth

on

the sensor wheel. (Note that

sO me


97/126

(

(

(

Y Vf

SI ART

TESI

=t_tnl

89/illS51.

erak

BS type

1 Sensor wheel with 94 teeth

2 Sensor wheel with 46 teeth

3 Not used

4 Not used

A couple of seconds after the

BS

version has

been selected, the tes ter wi ll au tomat ical ly

switch to Monitor Mode (manual test cycle).

Selection

of

an alternative ABS-system version

must be madewithin four seconds

of

power

up b y

pressing the two function buttonssimultaneous

ly.

The following

BS

versions are in use:

testers will display the figure 96 .)

ABS-type 1 indicates the automaticallychosen

system.

Saab9

The tests in this mode are the same as those in

Monitor Mode, except

that

here the tester

switchesautomaticallyfrom onetest to the next.

To enter Test Mode:

o Make sure that the tester i s in the Monitor

Mode, ready to measure wheel speed this is

the status the tester enters automatical ly

af ter t he A8S-system version has been

selected)

59 16

ASS-system tester


98/126

\

)

\

- I

====

Irno

faults have been detected, the display will

read

SYSTEM OK.

Saab9

o Drive the car at a speed above

km/h

6 mph).

Press the START

TEST

button.

TEST wi

II now start

to flash on the_.display, indicating that the Test

Mode has.beerrinitiated.

If

the tes ter does not enter the Test Mode, re

main in Monitor Mode and check the wheel sen

sor signal amplitude for each wheel.

For accurate test results, the car must be driven

for at least three minutes at a speed of about

7

knn/h

42 mph). The test resultswill not beaf

fecter by the car s topp ing and start ing in re

sponse to traffic conditions. The test cycle for

eachwhe_el takes,about two seconds; testing the

accumwlatorpressuretakes a

bi t

longer approx.

four seconds) because the relays are also

checked.

The tes ter wi ll bleep each time a fault is de

tected.

Rectify any faults by locking up the errorcode

in

the fault-diagnosis routine.

Testing will continue until the tester is switched

of f orthe START TEST button is pressed for about

three seconds.

To

read thetest results:

1 Stop the car.

11

not switch

of f

the ignition.

2 Wait until the display indicates FR, FL,

RL

or

RR and press the START

TEST

button.

If any faults have been detected,

ERROR

wi II ap-

pear on the display followed by a figure indicat-

ingthe number

of faults

found.

To read the error codes, press the NEXT ERROR

ABS system tester

59 17

.


99/126

O E button and the error codes will be dis-

played. Pressthe button again to read each suc-

cessive error code.

If several error codes are displayed togetherthey

must be

investigated and rectified

in

the follow-

ing order:

E002

EE24

EOOl

E033

E422

EE25

E009 E034

E523

EOll

E010

E035

E624

E008

E015 E132

E725

E320

E016

PRES

EE22

E014

E017

EE23

E032

E018

To return to MonitorMode, press one

ofthe

func-

tion

buttons.

Saab 9()O

,.

59 18

ASS-system teste r


100/126

. .J

r - - - \

Saab9

The t est er wi ll bleep each t im e a fault i s de

tected.

Make sure that the te ster is in Monitor Mode

entered automatically

by

the tes ter a fte r the

ASS-system version has been selected)

The car must be

at

a standstill with the engine

running.

Press one

of

the

FUNCTION

buttons

to

enter the

Valve Test Mode. The SS Anti-lock) warning

light on the ins trumen t p ane l wil l c ome on and

remain on throughout the test sequence.)

Pressithe

ST RT TEST

button.

TEST

will now flash

on the display, indicatingthat the

test

sequence

has been initiated.

To enterthe Valve Test Mode:

ABS-:system tester 59 19

Note

When the rear inlet valve IR is to be tested ,

choose a p lace to stop the car

Where

it

can re-

main parked whi lst the remain ing valves are

IFL

Inlet Front Left

IFR Inlet Front Right

IR

Inlet Rear

: The valves are tested in the fol lowing order:


101/126

This sequence will be repeated automatically to

test

the

other inlet valves.

Press down hard on

the brake pedal as soon as

the text appears. The tester wil l measure the

wheel retardation as the car s lows from 15 to

13

km/h.

l fPl

BR KlE

As. soon as

the

car has stopped, re lease the

brake pedal. Do nottouchthe brake pedal again.

When

thetest

sequence for the

inlet

valves has

been completed, the tester wil l automat ical ly

continuethe nextsequence, i.e. testing the out-

let

valves and main valve.

Saab

Foot

off

the accelerator and

letthe

car coast. Do

not touch the brake pedal: use

the

handbrake

if

you need to slow the car down. Depress the

clut.ch pedal manuals only and be ready to

brake when APPLY BRAKE appears on

the

display

after

the

road speed has dropped to about

18

km/h or

11

mph .

Drive

the

car

at

a speed above

2

km/h 13 mph

but not

over

3

km/h 19 mph .

During

this

test, the fol lowing prompts wil l ap-

pear on

the

display in the order shown:

STOlP CAR

amd RIELEASE

BRAKE

tested.

O

ut l

et

Re

ar

r

ea

r o

u

tl e

t v

alv

e

O

u

tle

t F

ro

nt

R i

gh

t

O

u

tle

t F

ro

nt

Le

ft

M

a

in

va

lve

OR

O

F

R

O

FL

N ote

D

ur

in

g t

e s

ti n

g

of

th

e

m a

in

v

alv

e M

V

th

e

br

ak

e

p

ed

al

w

ill

pu

ls

at e

s

tro

va

Rv

es 3

l

\ld

m

a

in

va

h

le

T

he

o

u tl

e t

va

lve

s

an

d m

a

in

va

lve

a

re

te

st e

d in

th

e

fo l

lo w

in

g

or

de

r:

5

9

2

A

S

S

-s

y

st

em

te

s

te

r


102/126

S

aa

b

T

he

se

q

ue

nc

e w

il

l b

e

re

pe

ate

d

a

ut o

m

a t

ic a

lly

t

o

test th e

ot h

er

o

u tl

e t

va

lv

es

an

d

th

e m

a

in

va

lve

.

Q

S

tR

O

K

E

->

a

Jtril

d

I

ru

ue

O

ff

Bo

th

fla

sh

in

g

T

he

pe

da

l

sh

ou

ld

pu

ls

ate

o

r t

he

re

s

ho

uld

be

e

x

c

es

si

ve

p

ed

al

tra

v

el

wh

e

n

th e

p

ed

a

l i

s d

e

pr e

s

se

d. If

so

, s

w

itc

h o

ff

th

e

ig n

it

io n

w

ith

in

10

se

c

onds

to

send

an

acknowl edg em ent to th e te ste r.

If

th

e

pe

da

l d

oe

s

no

t

re s

po

n

d a

s

de

sc

rib

e

d, d

o

n

o t

sw

itc

h o

ff

t

he

i

gn

it io

n

. W

a

it

ab

ou

t 2

0

s

ec

o

nd

s f

ort

he

n

ex

t p

ro

m

pt R

E

LE

AS

E

B

RA

KE

to

ap

pe

a

r o

n th

e

d

isp

la

y.

If

n

o

fa

u lt

s

ha

ve

be

e

n d

e

te c

te

d,

th

e

dis

pl

ay

w

ill

r

ea

d SY

ST

EM

O

K.

Pr

es

s

do

wn

h

ard

on

th

e

b

ra

ke

p

ed

al

a

s s

oo

n

as

t

he

te

x t

ap

pe

ar

s.

S

wi

tch

o

n t

he

ig

ni

tio

n

tu

rn

ke

y t

o d

ri

ve

po

si

ti o

n

R

El

EA

S

E

I8

lR

AK

IE

B

ef o

re

s

ta r

tin

g

th

e t

es

t:

o

Th

e c

ar

m

us

t be

at

a s

ta

nd

st

il l

wi

th

th

e e

n

gi n

e

sw

itc

he

d

of

f.

D

u

ri n

g th

is

te s

t,

th

e

fo

ll o

w i

n g

p

ro

m p

ts

w

il l

ap

p

ea

r

on

th

e

dis

pl

ay

in

th

e

or

de

r s

ho

wn

:

ng

ly

.

Do

n o

t t

ou

ch

th

l;Y

b

ra

ke

p

ed

al

. B

ra

ki

ng

is

t

a

llo

w

ed

.

A

ft

er

a

bo

ut

fiv

e

se

co

n

ds

, t

he

p

um

p

w

il l

h

av

e

. r

ai s

ed

t

h e

p

re

ss

ur e

i

n

th

e

ac

cu

m

ul a

to

r t

o

ap

pro

x.

18

0

b

ar

2

61

0

p

si

a

nd

R

EL

EA

SE

B

RA

K

E

w i

ll d

is

ap

pe

ar

fr

om

th

e

di

sp

la

y.

A I

?P

lV

[sl

R

l}{l

ASS-system tester 5 90-21

If anyfaults have been detected

ERROR

will ap

pear on the display followed by a figure indicat

ing the number

of

faults found.

To

read the error codes press the NEXT ERROR

O E bu tto n and t he error codes wil l be di s


103/126

E002

EE24

EOOl E033

E422

EE25

E009 E034

E523 EOll E010 E035

E624

E008

E015 E132

E725

E320 E016 PRES

EE22

E014 E017

EE23

E032 E018

Saab

To return to Monitor Mode press one

ofthe

func

tion

buttons.

If several error codes are displayed togetherthey

must

be investigated and rectified in the follow

ing order:

played. Press the button again to read each suc

cessive error code.

59 22

ASS-system

tester

After

the

t es te r has been powered up and the

ABS-sY tem vers ion selected, the tester wil l

u t o r r i ~ i l l y

enter the Monitor Mode.

The following tests can now

performed:

Wheel speed

Wheel sensor signal amplitude signal

strength)

Sensor wheel eccentricity out-of-round)


104/126

Wheel-sensor circuit continuity and function

check


i f

pressure sensor con

nected)

The test er will bleep each time a fault is de

tected.

Saab9

SS system tester

59 23

This test must be carried out with the car being

driven

at

a steady speed.

Km/h will appear

on

the display together with a

number, indicating the speed of the wheel in

km/h.

FR on the display indicates that the front right

. wheel is being tested. .


105/126

SfAR

T f

XT

RROR

CODE

= I_ ell L

t ~ 9

5

nk s

Some of the valve segments may flash during

this

test ; this is qui te normal and can be dis-

regarded.

Saab

If the pressure sensor is connected, PRESSURE

will appear

on

the display together with a value

indicating the accumulator pressure in bar this

is the working pressure of the brake system .

To

test the speed of the other wheels, press the

top FUN TION button. The wheels wil l now

be

tested in an anticlockwise sequence, as shown.

The

test can also

be

performed in a clockwise

sequence - press the bottom

FUN TION

button.

The values should

be

rough ly the same for al l

four wheels.

ST RT

TEST

=laml l I r

9g6S1

W h e e ~ L s e l l l s o l i sogli1lai a m l J l ~ D t l l O d e

Th'fs test must be carried out with the car being

di: i,v.en at a steady speed.

Press; the top

FUNCTION

button for about three

seconds.

The

tester will nowmeasure the signal

ampPitude from the wheel sensors.

590 24

ASS-system tester


106/126

\ R SSUR

B

h

NEXT

ERROR

CODE

ST RT

TEST

=I.m In l

/19

OG 51

en

5.2 - ABS Braking System [OCR]

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Transcript of 5.2 - ABS Braking System [OCR]