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TABLE OF CONTENTS

1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

1.1 SYSTEM COVERAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11.2 SIX-STEP TROUBLESHOOTING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . .1

2.0 IDENTIFICATION OF SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

3.0 SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION . . . . . . . . . . . . . . . . . . . . . .1

3.1 TEVES MARK 20I SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13.1.1 PEDAL FEEL/VEHICLE CHARACTERISTICS. . . . . . . . . . . . . . . . . . . . .23.1.2 SYSTEM COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23.1.3 ABS AND BRAKE WARNING INDICATORS . . . . . . . . . . . . . . . . . . . . . .23.1.4 CONTROLLER ANTILOCK BRAKE (CAB) . . . . . . . . . . . . . . . . . . . . . . .23.1.5 HYDRAULIC CONTROL UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.1.6 RELAYS/SWITCHES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.1.7 SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

3.2 DIAGNOSTIC TROUBLE CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43.2.1 SYSTEM INITIALIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

3.2.2 DIAGNOSTIC MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43.2.3 INTERMITTENT DIAGNOSTIC TROUBLE CODES . . . . . . . . . . . . . . . .43.3 AXLE LOCK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

3.3.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43.3.2 DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

3.4 USING THE DRBIII . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53.5 DRBIII ERROR MESSAGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

3.5.1 DRBIII DOES NOT POWER UP (BLANK SCREEN) . . . . . . . . . . . . . .53.5.2 DISPLAY IS NOT VISIBLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

4.0 DISCLAIMERS, SAFETY WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

4.1 DISCLAIMERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54.2 SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

4.2.1 TECHNICIAN SAFETY INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . .64.2.2 VEHICLE PREPARATION FOR TESTING . . . . . . . . . . . . . . . . . . . . . . . .64.2.3 SERVICING SUB-ASSEMBLIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64.2.4 DRBIII SAFETY INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

4.3 WARNING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64.3.1 VEHICLE DAMAGE WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64.3.2 ROAD TESTING A COMPLAINT VEHICLE . . . . . . . . . . . . . . . . . . . . . . .7

4.4 DIAGNOSIS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

5.0 REQUIRED TOOLS AND EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

6.0 GLOSSARY OF TERMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

7.0 DIAGNOSTIC INFORMATION AND PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

BRAKES (CAB)CAB POWER FEED CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10CONTROLLER FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13G-SWITCH NOT PROCESSABLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15LEFT FRONT SENSOR CIRCUIT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19LEFT REAR SENSOR CIRCUIT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

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TABLE OF CONTENTS - Continued

RIGHT FRONT SENSOR CIRCUIT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19RIGHT REAR SENSOR CIRCUIT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19LEFT FRONT SENSOR SIGNAL FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22LEFT REAR SENSOR SIGNAL FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22RIGHT FRONT SENSOR SIGNAL FAILURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22RIGHT REAR SENSOR SIGNAL FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22PUMP MOTOR NOT WORKING PROPERLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

SYSTEM OVER VOLTAGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29SYSTEM UNDER VOLTAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31*ABS WARNING INDICATOR ALWAYS ON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33*ABS WARNING INDICATOR INOPERATIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35*BRAKE LAMP SWITCH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37*FRONT AXLE LOCK INDICATOR REMAINS FLASHING . . . . . . . . . . . . . . . . . . . . . . .38*NO RESPONSE FROM CONTROLLER ANTILOCK BRAKE . . . . . . . . . . . . . . . . . . . .40*REAR AXLE LOCK INDICATOR REMAINS FLASHING . . . . . . . . . . . . . . . . . . . . . . . .42*REAR AXLE LOCK INOPERATIVE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

VERIFICATION TESTSVERIFICATION TESTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

8.0 COMPONENT LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

8.1 CONTROLLER ANTILOCK BRAKE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .498.2 DATA LINK CONNECTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .498.3 G-SWITCH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .498.4 FUSES & RELAYS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.5 WHEEL SPEED SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.6 WHEEL SPEED SENSOR CONNECTORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.7 BRAKE SWITCHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

8.7.1 PARKING BRAKE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .518.7.2 BRAKE SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

9.0 CONNECTOR PINOUTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

AXLE LOCK SWITCH (OFF-ROAD PACKAGE) - 8 WAY. . . . . . . . . . . . . . . . . . . . . . . .53BRAKE LAMP SWITCH - GRAY 6 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53BRAKE WARNING INDICATOR SWITCH - BLACK 2 WAY . . . . . . . . . . . . . . . . . . . . . .53C115 (OFF-ROAD PACKAGE) - BLACK (ENGINE SIDE) . . . . . . . . . . . . . . . . . . . . . . .53C115 (OFF-ROAD PACKAGE) - BLACK (FRONT FEEDBACK OVERLAY SIDE). . . . .54C116 (OFF-ROAD PACKAGE) - LT GRAY (ENGINE SIDE) . . . . . . . . . . . . . . . . . . . . . .54C116 (OFF-ROAD PACKAGE) - LT GRAY (REAR FEEDBACK OVERLAY SIDE) . . . .54CLUTCH PEDAL POSITION SWITCH (M/T) - BLACK 2 WAY . . . . . . . . . . . . . . . . . . . .54CONTROLLER ANTILOCK BRAKE - 25 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

DATA LINK CONNECTOR - BLACK 16 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55FRONT LOCKER INDICATOR SWITCH (OFF-ROAD PACKAGE) - BLACK 2 WAY . .56FRONT LOCKER PUMP (OFF-ROAD PACKAGE) - LT GRAY 3 WAY . . . . . . . . . . . . .56G-SWITCH (LHD) - 3 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56INSTRUMENT CLUSTER C1 - 12 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56INSTRUMENT CLUSTER C2 - 16 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57LEFT FRONT WHEEL SPEED SENSOR - 2 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57LEFT FRONT WHEEL SPEED SENSOR (SENSOR SIDE) - 2 WAY . . . . . . . . . . . . . .57LEFT REAR WHEEL SPEED SENSOR - 2 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58LEFT REAR WHEEL SPEED SENSOR (SENSOR SIDE) - 2 WAY . . . . . . . . . . . . . . . .58

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TABLE OF CONTENTS - Continued

FUSES (PDC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60FRONT LOCKER RELAY (IN PDC/OFF-ROAD PACKAGE). . . . . . . . . . . . . . . . . . . . . .60REAR LOCKER RELAY (IN PDC/OFF-ROAD PACKAGE) . . . . . . . . . . . . . . . . . . . . . . .60REAR LOCKER INDICATOR SWITCH (OFF-ROAD PACKAGE) - BLACK 2 WAY. . . .61REAR LOCKER PUMP (OFF-ROAD PACKAGE) - LT GRAY 3 WAY . . . . . . . . . . . . . .61RIGHT FRONT WHEEL SPEED SENSOR - BLACK 2 WAY . . . . . . . . . . . . . . . . . . . . .61RIGHT FRONT WHEEL SPEED SENSOR (SENSOR SIDE) - 2 WAY . . . . . . . . . . . . .62

RIGHT REAR WHEEL SPEED SENSOR - BLACK 2 WAY . . . . . . . . . . . . . . . . . . . . . .62RIGHT REAR WHEEL SPEED SENSOR (SENSOR SIDE) - 2 WAY . . . . . . . . . . . . . .62VEHICLE SPEED SENSOR - BLACK 3 WAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63

10.0 SCHEMATIC DIAGRAMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65

10.1 TEVES MARK 20I CONTROLLER ANTILOCK BRAKE - ABS . . . . . . . . . . . . . . .6510.2 AXLE LOCK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66

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NOTES

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1 .0 I N T ROD UC T I ON

The procedures contained in this manual include

all the specifications, instructions, and graphics

n e ed e d t o d ia g n os e t h e 2 00 5 T J C h a s s is s ys t e m

problems: Teves Mark 20i Antilock Braking System

(ABS) and Axle Lock. The diagnostics in this man-

ual are based on the failure condition or symptom

being present at time of diagnosis.Follow the recommendations below when choos-

ing your diagnostic path.

1 . F i r s t m a k e s u r e t h e D R BI I I is communicating

w i t h t h e C A B . I f t h e D R B I I I displays a No

Response condition, you must diagnose that

first.

2. Read DTCs (diagnostic trouble codes) with th e

DRBIII.

3. If no DTCs are present, identify t he customer

complaint.

4. Once t he DTC or customer complaint is identi-

fi ed , l oca t e t h e m a t c h in g t e s t i n t h e Ta b le of Contents and begin t o diagnose the symptom.

All component location views are in Section 8.0.

All connector pinouts are in Section 9.0. All sche-

matics are in Section 10.0.

An asterisk (*) placed before the symptom de-

scription indicates a customer complaint.

When repairs a re r equired, refer t o the a ppropri-

a t e s er vice m a n u a l for t h e p r op er r e m ova l a n d

repair procedure.Diagnostic procedures change every

year. New diagnostic systems may be added; carryover

syst em s m ay b e en h an ced . R E AD T H IS M AN U AL

BEFORE TRYING TO DIAGNOSE A VEHICLE DI-

AGNOSTIC TROUBLE CODE. It is recommended

that you review the entire manual to become familiar

with all new and changed diagnostic procedures.

After using this book, if you have any comments

or recommendations, please fill out the form at the

back of the book and mail it back to us.

1. 1 SYSTEM COVERAGE

This diagnostic manual covers the Teves Mark

20i Antilock Braking System (ABS) found on the

2005 Jeep Wrangler. Diagnosis of the Axle Lock is

covered in this manual.

1. 2 SIX-STEP TROUBLESHOOTINGPROCEDURE

Diagnosis of the a ntilock brak e system is done in

six basic steps:

verification of complaint

verificat ion of any r elated symptoms

symptom analysis

problem isolation

repair of isolated problem

verification of proper operation

2 . 0 I D EN T I F I C AT I ON OFSYSTEM

Vehicles equipped with the Teves Mark 20i an-

ti lock brake system can be identified by the pres-ence of t he hydraulic contr ol unit (HCU) located

un der t he h ood nea r t he power bra ke booster. Vehi-

cles equipped with Axle Lock can be identified by

the presence of the Axle Lock Switch located on the

lower center of the instrument panel.

3 . 0 SYST EM D ESCR I PT I ON A N DFUNCTIONAL OPERATION

3.1 TEVES MARK 20I SYSTEM

DESCRIPTION

An electronic control module is used to monitor

wheel speeds and to modulate (control) hydraulic

p r e s s u r e i n e a c h b r a k e c h a n n e l t o p r e v e n t w h e e l

lock-up during braking.

During a non-ABS stop, the system functions a s a

standar d front/rear split configuration. The pri-

mary hydraulic system supplies brake fluid pres-

sure to th e front brakes, and the secondary h ydrau-

lic system supplies the rear brakes. A conventional

combination/proportioning valve is used.

D u r i n g a n A B S s t o p , t h e s y s t e m s t i l l u s e s t h e

front/rear hydraulic split; however, the brakes sys-

t e m p r e ss u r e i s f u r t h e r s p li t i n t o t h r e e con t r o l

chan nels. During ABS operation, the front wheels

are controlled independently an d are on two sepa-

r a t e con t r o l c h a n n e ls . T h e r e a r w h ee ls a r e con -

trolled together thr ough one control chann el. By

u s in g a s e pa r a t e con t r o l c h a n n e l f or e a ch fr on t

wheel, m ore steering control is maintained during

maximum braking.

Du rin g an an tilock stop, wh eel lock-up d oes not

n e ce s sa r i ly m e a n t h a t t h e w h e el h a s l ock e d, i t

m e a n s o n ly t h a t t h e w h e el i s t u r n i n g s low er t h a n

th e veh icle speed. This is called wheel s lip an d isindicated as a percentage. 0% slip means that the

wheel is r olling free an d 100% slip means tha t the

wheel is locked. The antilock system maintains an

average of approximately 20% wh eel slip.

I t i s i m p or t a n t t o r e m e m be r t h a t t h e a n t i lock

brake system does not shorten the vehicle stopping

distance under all driving conditions, but provides

improved control of the vehicle while stopping.

Vehicle stopping distance is still dependent on ve-

hicle speed, weight, t ires, road surface, and other

factors.

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3. 1.1 PEDAL FEEL/VEHICLE

CHARACTERISTICS

There are several pedal feel/vehicle characteris-

tics th at ar e considered norma l for a ntilock braking

that may require further explanation.

When stopping conditions activate the ant ilock

b r a ke s, t h e d r iv er m a y fe el s om e vib r a t ion s /

p u l s a t i o n s i n t h e b r a k e p e d a l a n d m a y h e a r t h esolenoid valves clicking a nd the pump motor run -

ning. The vibrations/pulsations are caused by the

isolating, building an d d ecaying of brake fluid pr es-

s u r e w it h in t h e b r a ke lin e s. T h e A BS p r ev en t s

complete wheel lock-up, but some wheel slip is

required for t he best brak ing performa nce. This slip

may result in some tire chirping, depending on the

r oa d s u r fa ce . T h is ch i r p in g s h ou l d n ot b e i n t er -

preted as total wheel lock-up. Total wheel lock-up

leaves black tire marks on dry pavement. Antilock

braking may leave some light m arks.

At the end of an ABS stop, the ABS system may

not function below 5 Km /h (3 mph). There ma y be aslight brake pedal drop anytime the ABS is deacti-

vated.

In case of braking on a bumpy sur face, th e ABS

module may detect wheel locking t endencies du e to

wheel hop and cycle ABS. In that event the brake

pedal may pulsate with a perceived loss of deceler-

ation. ABS braking ma y also be activated at t imes

while on dry pavement with san d, gravel, or other

loose debris on the road.

It should be noted that the pulsating pedal feel

chara cteristic will not illum inate t he bra ke warn ing

indicators or set a diagnostic trouble code that is

stored in the Controller Antilock Brake (CAB).

When investigating a hard pedal feel, inspect the

sensor and tone wheel teeth for chips/broken teeth,

damaged sensor pole t ips, excessive ru nout of th e

tone wheel, or excessive gap.

3. 1.2 SYSTEM COMPONENTS

A n t i l o c k B r a k e S y s t e m

controller antilock brake (CAB)

vacuum booster

mast er cylinder (w/center valves)

hydraulic control unit (HCU)valve block a ssembly: 6 valve solenoids (3 inlet

valves, 3 outlet valves), 3

accumulators

pum p/motor a ssembly: 1 motor

2 p u m p s

G (acceleration) switch

1 proportioning valve

4 wheel speed sensor/tone wheel assemblies

ABS warning indicator

fuses and wiring harness

fluid reservoir (integral part of master cylinder

assembly)

3. 1.3 ABS AND BRAKE WARNING

INDICATORS

The amber ABS warning indicator is located in

t h e i n st r u m e n t cl u st e r. I t i s u s e d t o i n for m t h edriver tha t th e ant ilock function h as been tu rn ed off

d u e t o a s ys t e m m a l fu n c t ion . O n a T J m od e l t h e

warning indicator is controlled by the CAB and the

ABS relay. The CAB controls the indicator by di-

rectly groun ding t he ABS relay contr ol circuit. The

ABS relay grounds the indicator circuit when it is

de-energized.

The red brake warning indicator is located in the

instrument cluster. I t can be activated by applica-

tion of the parking brake, low brake fluid level or by

turn ing the ignition switch to th e sta rt position.

3. 1. 4 CONTROLLER ANTILOCK BRAKE(CAB)

T he con t r oller a n t ilock b ra k e (C AB ) is a

microprocessor-based device tha t monitors wheel

speeds and controls the antilock functions.

The primary functions of the CAB are:

monitor wheel speeds

detect wheel locking tendencies

control fluid pressure modulation to the brakes

during antilock stop operation

monitor the system for proper operation

provide communication to the DRBIII while in

diagnostic mode

contr ol t he ABS relay

store diagnostic information in non-volatile mem-

or y

The CAB continuously monitors the speed of each

wheel. When a wheel locking tendency is detected,

th e CAB will comma nd t he app ropriate valve in t he

H C U t o m od u la t e b r a ke flu id p r es su r e t o t h a t

wheel. Brake pedal position is maintained during

an antilock stop by being a closed system with the

use of three accumulators. The CAB continues to

contr ol pressure in individual hydraulic circuitsun til a wheel locking t endency is no longer pr esent.

T h e C A B t u r n s o n t h e p u m p / m o t o r d u r i n g a n a n -

tilock stop.

The a ntilock brake system is constan tly moni-

tored by the CAB for proper operation. If the CAB

d e t ect s a s ys t e m m a l fu n c t ion , i t ca n d is a b le t h e

a n t ilock s ys t em a n d t u r n on t h e A BS w a r n in g

indicator. If t he ant ilock function is disabled, the

system will revert to standard base brake system

operation.

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The CAB inpu ts include th e following:

four wheel speed sensors

brake lamp switch

ignition switch

battery voltage

diagnostic communication

G switch (acceleration switch)

The CAB outputs include the following:

six valve/solenoid drivers

pump/motor actuation

ABS warning indicator control

diagnostic communication

3.1. 5 HYDRAULIC CONTROL UNIT

The hydraulic control un it (HCU) conta ins t he

valve block assembly, three accumulators, and the

pump/motor assembly.

Va l v e B l o c k A s s e m b l y : The valve block assem-

bly contains 6 valves with three inlet valves andt h r e e ou t l et v a lv es . T h e i n le t v a lv es a r e s p r in g -

loaded in t he open position a nd t he outlet valves are

s p r in g l oa d e d i n t h e cl os e d p os it i on . D u r in g a n

antilock stop, these valves are cycled to maintain

the proper slip ratio for each channel. If a wheel

locks, the inlet valve is closed to prevent any further

pressure increase. Then the outlet valve is opened

t o r e l e a s e t h e p r e s s u r e t o t h e a c c u m u l a t o r s u n t i l

the wheel is no longer slipping. Once the wheel is no

longer slipping, the outlet valve is closed and the

i n le t v a lv e i s op e n ed t o r e a p pl y p r e s s u r e. I f t h e

wheel is decelerating within its predetermined lim-

its (proper slip ratio), both valves will close to hold

the pressure constant.

P u m p / M o t o r A s s e m b l y : T h e p u m p /m ot or a s -

sembly pr ovides t he extra amount of fluid needed

durin g ant ilock br aking. The pu mp is su pplied fluid

tha t is released to th e accum ulators when t he outlet

valve is opened during an antilock stop. The pump

is also used to drain the accumulator circuits after

the ant ilock st op is complete. The pu mp is operat ed

by a n integral electric motor. This motor is con-

trolled by the CAB. The CAB turns on the motor

when an antilock stop is detected. The pump con-

tinues to run during the an tilock stop and is tu rnedoff a p p r ox im a t e ly 3 -5 s e con d s a ft e r t h e s t op i s

com p le t e. T h e p u m p m e ch a n i s m con s is t s of t w o

opposing pistons operat ed by a n eccentr ic cam . One

piston supplies the primary hydraulic circuit . The

opposing piston supplies the secondary hydraulic

circuit . In operation, one piston draws fluid from

the accum ulators. Th e opposing piston pum ps fluid

to the valve body solenoids. The CAB monitors the

pump/motor opera tion.

A c c u m u l a t o r s : The accumulators provide tem-

porary fluid storage during a n a ntilock stop an d ar e

drained by the pump/motor.

3.1.6 RELAYS/SWITCHES

R e l a y s : The ABS Relay is located in the power

distribution center (PDC). When the relay is de-

energized, it supplies a ground to turn on the ABS

warning indicator. The ABS relay is controlled byt h e C AB . T h e C AB e n er g iz es t h e r e la y w h e n i t

receives an ignition input signal.

3.1. 7 SENSORS

Wh e e l S p e e d S e n s o r s a n d To n e Wh e e l s : On e

wheel speed sensor (WSS is located at each wheel

a n d s en d s a s m a ll AC s ign a l t o t h e C on t r olle r

Antilock Brake (CAB). This voltage is generated by

m a g n et i c i n d u ct i on w h e n a t oot h e d s e n sor r i n g

(tone wheel) passes by a st at iona ry m agnetic sensor

(wheel speed sensor). The CAB converts the AC

signals into digital signals for each wheel.The front wheel sensor is atta ched t o a boss in th e

steering knu ckle. The tone wheel is an integral par t

of t h e fr on t a x le s h a ft . T h e r e a r s p ee d s e n sor i s

mounted in t he caliper ada pter plat e (rear disc only)

a n d t h e r e a r t o n e w h e e l i s a n i n t e g r a l p a r t o f t h e

rear rotor h ub. The front wheel speed sensor air gap

is NOT adjustable. The correct front wheel speed

sensor air gap is from 0.40mm to 1.3mm (0.016 t o

0.051). P r e fe r r ed r e a r s e n sor a i r g a p f or d r u m

brak e systems is 1.1mm (0.043). Acceptable a ir ga p

range is 0.92mm to 1.275mm (0.036 to 0.050). All

wheel speed sensors have a resistance between 900

and 1300 ohms.Correct ant ilock system operation is dependent

on correct wheel speed signals from the wheel speed

sens ors. The vehicles wheels a nd t ires sh ould all be

the sa me size an d type. In addition, the tires should

be inflated to the recommended pressures for opti-

mum system operation. Varia tions in wh eel and tire

size or significant variations in inflation pressure

can produce inaccurate wheel speed signals; how-

ever, the system will continue to function when

using the mini-spare. When driven over rough road

surfaces, the rear wheel speed sensor signals may

be erratic and cause a false trouble code.

G ( A c c e l e r a t i o n ) S w i t c h : The CAB monitorst h e a cce le r a t ion s w it ch a t a l l t i m es . T h e s w it ch

a s s em b ly con t a i n s t h r e e m e r cu r y s w it ch e s t h a t

monitor vehicle deceleration rat es (G-force). Sud-

den, rapid changes in vehicle and wheel decelera-

tion rate trigger t he switch, sending a signal t o the

CAB. The switch a ssembly responds to t hree decel-

eration rates; two for forward braking and one for

rearward braking.

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3. 2 DIAGNOSTIC TROUBLE CODES

The Teves Mar k 20i Ant ilock Bra ke Syst em (ABS)

module may report any of the following diagnostic

trouble codes:

Controller Failure

G Switch Not Processable

Left Front Sensor Circuit Failure Left Front Sensor Signal Failure

Left Rear Sensor Circuit Failure

Left Rear Sensor Signal Failure

CAB Power Feed Circuit

System Over voltage

System Under voltage

Pump Motor Not Working Properly

Right Front Sensor Circuit Failure

Right Front Sensor Signal Failure

Right Rear Sensor Circuit Failure

Right Rear Sensor Signal Failure

Diagnostic trouble codes are retained in memory

u n t i l e r a s e d u s i n g t h e D R B I I I, or aut omatically

erased after 255 key cycles.

3.2.1 SYSTEM INITIALIZATION

S ys t em in it ia liza t ion s t a r t s w h en t h e k ey is

turned to RUN. At this point, the CAB performs a

complete self-check of all electrical components in

the antilock brake systems.

At around 19 km/h (12 miles per hour), the pump

motor is briefly activated to ensure operation, and

wheel speed sensor circuitry is checked. If the brakepedal is applied when the vehicle reaches 19 km/h

(12 mph), this check will be delayed until 40 km/h

( 2 5 m p h ) . I f , d u r i n g t h e d y n a m i c t e s t , t h e b r a k e

p ed a l is a p pl ie d, t h e d r iv er m a y fe el t h e t e st

t h r o u gh b r a k e p e d a l p u l s a t ion s . T h i s i s a n or m a l

condition. Throughout the remainder of the drive

cycle, ongoing tests are performed, and the CAB

monitors ABS circuits for continuity.

If any component causes a diagnostic trouble code

during system initialization or dynamic check, the

CAB will illuminate the ABS warning indicator.

3.2.2 DIAGNOSTIC MODETo enter diagnostic mode, vehicle speed must be

below 10 km/h (6 m ph), a no response message

will be displayed by the DRBIII. The following a re

chara cteristics of diagnostic m ode:

The ABS warning indicator will f lash. If a hard

d ia g n os t ic t r ou b le cod e i s p r e se n t , s u ch a s a

Speed Sensor Circuit or Signal Failure t rouble

code or CAB P ower Feed Circuit diagnostic trou-

ble code, the indicator will be illuminated without

blinking and limited diagnostic operations only

will be a vailable u nt il the diagnostic tr ouble code

condition is corrected.

Antilock operation is disabled.

3. 2.3 INTERMITTENT DIAGNOSTIC

TROUBLE CODES

If the malfunction is not present while perform-ing a test procedure, the diagnostic procedures will

not locate the problem. In this case, the code can

on ly s u gge st a n a r e a t o i n sp ect . C h eck for t h e

following:

loose or corr oded connections

dam aged components (sensors, tone wheels espe-

cially)

damaged wiring

excessive axle shaft runout

brake system hydraulic leaks

base brake system problems, non-ABS related.If no obvious p roblems ar e foun d, era se diagn ostic

trouble codes and, with the key on, wiggle the wire

ha rness an d connectors. Recheck for codes per iodi-

cally a s you work thr ough the system. This proce-

d u r e m a y u n c ov er a n i n t er m i t t en t or d iffi cu l t t o

locate malfunction.

3.3 AXLE LOCK

3.3.1 GENERAL

For this vehicle, the Axle Lock has no dedicated

module controller. A manual switch located on theinstrument panel controls th e system. No DTCs

will occur for this system.

3.3.2 DESCRIPTION

The a xle lock h as the ability to lock the front and

rear axle differentials. The system components are

the instrument cluster, axle lock switch, front and

rear locker relays, front a nd r ear locker pu mps, an d

locker ind icat or switches. To operat e both lockers

three requirements need to be met:

1. ignition in t he ON position

2. tran sfer case ran ge sensor indicating 4 LOWr a n g e

3. vehicle speed less tha n 16km/h (10 mph)

The 16km/h (10 mph) engagement is for engage-

ment only. All axles will r emain locked if vehicle

speed does not exceed 72 km/h (45 mph).

The instrument cluster has the control logic that

monitors these requirements. If the requirements

are not met the axle lock switch will be disabled.

The axle lock switch receives the enable signals

from the instrument cluster. Any subsequent down-

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ward press of the axle lock switch will operate the

front locker relay and front locker pump. The first

downward press on the axle lock switch locks the

r e a r a x le , t h e s e con d d ow n w a r d p r e ss l ock s t h e

front axle (rear is still locked), th e th ird downward

press unlocks the front axle (rear is still locked), the

fourth downward press locks the front axle (rear

axle is st i l l locked). An upward press on the axle

lock switch at any time will unlock any axle that iscur rent ly locked.

The enabled axle lock switch energizes the locker

r e la y a n d v ol t a ge i s s e n t t o t h e l ock e r p u m p t o

supply 5 psi of air t o the a xle allowing th e differen-

tial to lock up. The axle lock indicator on the

i n st r u m e n t cl u st e r fl a sh e s d u r i n g t h e t r a n s i t ion

state. The instrument cluster is seeking lock feed-

b a ck fr om t h e l ock i n g i n di ca t or s w it ch . Wi t h a

successful lock requ est th e axle lock indicator will

be illuminated and a chime will sound.

If an a xle is engaged t he a xle lock switch r emains

enabled until all axles are unlocked, regardless if

the key is removed from the ignition switch. If theignition key is removed and either axle is locked the

instrument cluster axle lock indicator to the cor-

responding axle will flash and the chime will sound

three t imes to alert of battery discharge. Flashing

axle lock indicators will continue until axles are

unlocked. Once the axles have been locked it will

remain locked until one of the following happens:

1. an upward press of the axle lock switch for all

locked axles or downward press for front axle

only

2. tra nsfer case is shifted out of 4 LOW ran ge

3. vehicle speed exceeds 72 km/h (45 mph)

4. loss of batt ery power

3.4 USING THE DRBIII

Refer t o the DRBIII user s guide for ins tr uctions

a n d a s s is t a n ce w it h r e a d in g d ia g n os t ic t r ou b le

codes, erasing trouble codes and other DRBIII

functions.

3.5 DRBIII ERROR MESSAGES

Under normal operation, the DRBIII will dis-

play one of only two error messages:

U s e r R eq u es t e d WAR M B oot or U s e r R e-

quested COLD Boot

This is a sa mple of such an error messa ge display:

ver: 2.14date: 26 J ul93file: key_itf.ccdate: Jul 26 1993line: 548err: 0x1User-Requested COLD Boot

Press MORE to switch between this displayand the application screen.Press F4 when done noting information.

3.5.1 DRBIII DOES NOT POWER UP

(BLANK SCREEN)

If the LE Ds do not light or no soun d is emitt ed at

star t up, check for loose cable conn ections or a bad

cable. Check the vehicle battery voltage (data link

16-way conn ector cavity 16). A min imum of 11 volts

is required to adequately power the DRBIII. Also,

check for a good ground at the DLC.

I f a ll con n ect ion s a r e p r op er b et we en t h eDRBIII and the vehicle or other devices, and the

vehicle bat tery is fully charged, an d inoperative

DRBIII may be the result of faulty cable or vehicle

wiring.

3.5. 2 DISPLAY IS NOT VISIBLE

Low temperatures will affect the visibility of the

display. Adjust the contrast to compensate for this

condition.

4.0 DISCLAIMERS, SAFETYWARNINGS

4.1 DISCLAIMERS

All information, illustrations, and specifications

c o n t a i n e d i n t h i s m a n u a l a r e b a s e d o n t h e l a t e s t

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informat ion available at the t ime of publication.

The right is reserved to make changes at any t ime

without notice.

4.2 SAFETY

4. 2. 1 TECHNICIAN SAFETY INFORMATION

WARNING: ENGINES PRODUCE CARBONMONOXIDE THAT IS ODORLESS, CAUSESSLOWER REACTION TIME, AND CAN LEADTO SERIOUS INJURY. WHEN THE ENGINE ISOPERATING, KEEP SERVICE AREAS WELLVENTILATED OR ATTACH THE VEHICLEEXHAUST SYSTEM TO THE SHOP EXHAUSTREMOVAL SYSTEM.

Set th e park ing brake a nd block the wheels before

t e s t in g or r e p a ir i n g t h e v eh i cl e. I t i s e sp e ci a ll y

important to block the wheels on front-wheel drive

vehicles; the parking brake does not hold the drivewheels.

When servicing a vehicle always wear eye protec-

tion and remove any metal jewelry such as watch-

bands or bracelets th at m ight make a n inadvertent

electrical contact.

Additional safety procedures can be found in the

service ma nu al. Following th ese procedures is very

important to avoid injury.

4. 2. 2 VEHICLE PREPARATION FOR

TESTING

M a k e s u r e t h e v e h i c l e b e i n g t e s t e d h a s a f u l l ych a r g ed b a t t e r y. I f i s d oe s n ot , fa l se d ia g n os t ic

trouble codes or error messages may occur.

4. 2.3 SERVICING SUB-ASSEMBLIES

Some components of the antilock brake system

are intended to be serviced in assembly only. At-

tempting to remove or repair certain system sub-

components may result in personal injury and/or

improper system opera tion. On ly those component s

with appr oved repair a nd inst allation pr ocedures in

the service manual should be serviced.

4.2.4 DRBIII SAFETY INFORMATION

WARNING: EXCEEDING THE LIMITS OF THEDRBIII MULTIMETER IS DANGEROUS. ITCAN EXPOSE YOU TO SERIOUS ORPOSSIBLY FATAL INJURY. CAREFULLYREAD AND UNDERSTAND THE CAUTIONSAND THE SPECIFICATION LIMITS.

Follow t he vehicle m an ufacturer s service speci-

fications at all times.

Do not use th e DRBIII if i t ha s been dam aged.

D o n ot u s e t h e t e st le a ds if t h e in s u la t ion is

damaged or if metal is exposed.

To a void electrical shock, do n ot touch the test

leads, tips or the circuit being tested.

C h oos e t h e p r op e r r a n g e a n d fu n c t ion for t h e

measurement. Do not try voltage or current mea-

surements that may exceed the rated capacity. Do not exceed the limits shown in the table below:

F U N CTION IN P U T LIMIT

Volt s 0 - 500 pea k volt s AC

0 - 500 volts DC

O h m s (r e si st a n ce )* 0 - 1 .1 2 m e goh m s

Frequency Measured

Frequency Generated

0 - 1 0 k H z

Tem per a t u r e -50 - 600C

-58 - 1100F

* Ohms cannot be measured if voltage is present.O h m s ca n b e m e a su r e d on l y i n a n on -p ow er e d

circuit.

Voltage between any terminal and ground must

not exceed 500v DC or 500v peak AC.

Use caution when measuring voltage above 25v

DC or 25v AC.

Use the low current shunt to measure circuits up

to 10A. Use the high current clamp to measure

circuits exceeding 10A.

When testing for the presence of voltage or cur-

r e n t , m a k e s u r e t h e m e t e r i s f u n ct i on i n g c or -

r e ct l y. Ta k e a r e a d in g of a k n ow n v ol t a ge orcurrent before accepting a zero reading.

When measuring current, connect the meter in

series with the load.

Disconnect the live test lead before disconnecting

the common test lead.

Wh en u sin g t h e m et er fu n ct ion , k eep t h e

DRBIII away from spark plug or coil wires to

avoid m easur ing error from outside inter ference.

4.3 WARNING

4. 3.1 VEHICLE DAMAGE WARNINGS

Before disconnecting any control module, make

s u r e t h e i gn i t ion i s O F F . F a i l u r e t o d o s o c ou l d

damage t he m odule.

When t esting voltage or continu ity at an y control

module, use the terminal side (not the wire end) of

the connector. Do not pierce wire insulation; this

will damage i t and eventually cause i t to fail be-

cause of corrosion.

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Be careful when performing electrical tests so as

to prevent accidental shorting of terminals. Such

mistakes can damage fuses or components. Also, a

second code could be set, making diagnosis of the

original problem more difficult.

4.3. 2 ROAD TESTING A COMPLAINT

VEHICLE

Some complaints will require a test drive as part

of th e r epair verificat ion procedure. The purp ose of

the test drive is to try to duplicate the diagnostic

code or symptom condition.

NOTE: After the repair of pump or speedsignal DTCs, the vehicle must be driven at 25km/h (15 mph) to clear the DTC from the CAB.

WARNING: BEFORE ROAD TESTING AVEHICLE, BE SURE THAT ALLCOMPONENTS ARE REASSEMBLED.

DURING THE TEST DRIVE, DO NOT TRY TOREAD THE DRBIII SCREEN WHILE INMOTION. DO NOT HANG THE DRB FROMTHE REAR VIEW MIRROR OR OPERATE ITYOURSELF. HAVE AN ASSISTANTAVAILABLE TO OPERATE THE DRBIII.

4.4 DIAGNOSIS

1. Your diagnostic test pr ocedure mu st begin with a

thorough visual inspection of the ABS for dam-

aged components or disconnected connectors.

T h e b r a k e l a m p s m u s t b e o p e r a t i o n a l p r i o r t ocontinuing.

2. Connect the DRBIII to the data link connector

located under the dash. If the DRBIII does not

power up, check the power and ground supplies

to t he conn ector.

3. Select Ant ilock Br ak es. Tur n t he ign ition on. If

t h e D RB I II disp lays No Resp onse, per form

the proper test .

4 . R ea d a n d r e cor d a l l A BS d ia g n os t ic t r ou b le

codes. If t he CAB P ower Feed Circuit tr ouble

cod e i s p r e se n t , i t m u s t b e r e p a i r ed p r ior t o

addressing any other DTCs. If any additionalcod e s a r e p r e se n t , p r oce ed t o t h e a p p r op r ia t e

test.

5. If there ar e no diagnostic trouble codes present,

s e le ct I n p u t s /O u t p u t s a n d r e a d t h e b r a k e

switch input a s you press and release th e brake

pedal. If the display does not m atch t he st ate of

the pedal, perform the appr opriat e test. Read th e

G-Switch stat us, with the vehicle on a level

su rfa ce, both swit ches sh ould r ead CLOSE D. If

the st atu s is not correct, perform t he appr opriate

test. If a problem with the ABS warning indica-

tor exists, refer to th e a ppropriate t est .

6. If no other problem are found, i t will be neces-

s a r y t o r o a d t e s t t h e v eh i cl e. T H E D R B I II

MU ST N OT B E CON NE CTE D TO TH E

D ATA L IN K C ON N E C T OR WH E N R O AD

T E S TI N G F O R P R O P E R A N TI LO CK O P -

E R AT IO N . T HE S YS T E M I S D I S AB L E D

WH I LE I N D I AG N OS T I C M OD E . Performseveral antilock stops from above 50 Km/h (30

m p h ) a n d t h e n r e p e a t s t e p s 2 , 3 , a n d 4 . I f a n y

diagnostic trouble codes are present, proceed to

the appropriate test .

7. The following conditions should be considered

NORMAL operat ion, a nd no r epair s sh ould be

attempted to correct them.

B r a ke p ed a l fe ed ba ck d u r in g a n AB S s t op

(clicking, vibrat ing)

Clicking, groaning or buzzing at 10 Km/h (6

mph) (drive off self test)

Groaning noise during a n ABS stop

S li gh t b r a k e p e d a l d r op a n d p op n oi se w h e n

ignition is initially turned on

Brake pedal ratcheting down at the end of an

ABS stop

8. If the complaint is ABS cycling at t he end of a

s t op a t low s pe ed s, it m a y b e c a us ed b y a

marginal wheel speed sensor signal. The sensor

a i r g a p , t on e w h e el con d it i on , a n d /or b r a k e s

ha nging up ar e possible cau ses of this condition.

9 . A ft e r a r oa d t e s t i n w h i ch n o p r o bl em s w er e

found, refer to any Technical Service Bulletinsthat may a pply.

5 . 0 R EQU I RED T OOL S A N DEQUIPMENT

DRBIII (diagnostic read-out box)

jumper wires

ohmmeter

voltmetertest lamp

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7 .0

DIAGNOSTI C I NFORM ATI ON AND

PROCEDURES

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S y m p t o m :

CAB POWER FEED CIRCUIT

W h e n M o n i t o r e d a n d S e t C o n d i t i o n :

CAB POWER FEED CIRCUIT

When Monitored: Ignition on. The CAB monitors t he F used B(+) circuit a t all times for

proper system voltage.

Set Condition: If the F used B(+) voltage is missing when the CAB detects th at a n intern al

main driver is not on, the Diagnostic Trouble Code (DTC) is set.

P O S S I B L E C A U S E S

INTERMITTENT DTC

B(+) CIRCUIT SHORTED TO GROUND

BLOWN FUSE - FUSED B(+) CIRCUIT

CAB - FUSED B(+) CIRCUIT SHORTED TO GROUND

FUSED B(+) CIRCUIT OPEN

NO B+ SUP PLY TO FUSE

CAB - FUSED B(+) CIRCUIT OPEN

TES T ACTION AP P LICAB ILITY

1 Tu r n t h e ign it ion on .

With the DRBIII, era se DTCs.Turn the ignition off.

Turn the ignition on.

Drive the vehicle above 25 km/h (15 mph) for at least 10 seconds.

Stop th e vehicle.

With the DRBIII, read DTCs.

Does the DRBIII display CAB Power Feed Circuit DTC present right now?

All

Yes G o To 2

N o Go To 9

2 Tu r n t h e ig ni t ion off.

Rem ove and Ins pect F us e 12 in the P D C.

Is the F us e blow n?

All

Yes G o To 3

N o Go To 6

10

BRAKES (CAB)

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Remove Fuse 12 from the PDC.

Disconnect the CAB h arn ess connector.

N o t e : Ch e c k c o n n e c t o r - C le a n / r e p a i r a s n e c e s s a r y .Using a test light connected to 12 volts, probe the Fused B(+) Circuit.

Does the test light illuminate brightly?

All

Yes Repair the Fused B(+) Circuit Shorted to Ground.

Perform ABS VERIFICATION TE ST - VER 1.

N o Go To 4



The CAB must be connected for the results of this test to be valid.

Using a test light connected to 12 volts, probe the Fused B+ circuit at the PDC fuse

term inal.

Does the test light illuminate brightly?

All

Yes Replace t he Controller Antilock Bra ke in accordance w ith the

Service Informa tion.


N o Go To 5

5 Tu r n t h e i gn it i on off.

If there are no potential caus es rem aining, view repair .

All

Continue

Replace the Fuse.

Perform ABS VERIFICATION TEST - VER 1.



Disconnect the CAB h arn ess connector.N o t e : Ch e c k c o n n e c t o r - C le a n / r e p a i r a s n e c e s s a r y .

M eas ure the res istance of the F us ed B+ circuit betw een the P D C fus e term inal and

the CAB connector.

Is the resistance below 5 ohms?

All

Yes G o To 7

N o Repair the Fused B+ circuit for an open.


7 R em ov e F u s e 1 2 fr om t h e P DC .


M eas ure the voltage of the F us ed B+ s upply to F us e 12 in the P D C.

Is the voltage above 10 volts?

All

Yes G o To 8

N o Repair the B+ Supply circuit for an open.


8 If t h er e a r e n o pot en t ia l ca u ses r em a in in g, view r epa ir. All

Repair

Replace t he Controller Antilock Brak e in accordance w ith the



11

BRAKES (CAB)

CAB POWER FEED CIRCUIT C o n t i n u e d

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Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or

partially broken wires.

Visually inspect th e r elated wire har ness connectors. Look for broken, bent, pu shedout, or corroded t ermina ls.

Refer to any Hotline letters or Technical Service Bulletins that may apply.

Were a ny pr oblems found?

All

Yes Repair as necessary.


N o Test Complete.

12

BRAKES (CAB)

CAB POWER FEED CIRCUIT C o n t i n u e d

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S y m p t o m :

CONTROLLER FAILURE


CONTROLLER FAILURE

When Monitored: Ignition on. The CAB monitors its int ern al microprocessors for correct

operation.

Set Condition: If the CAB detects a n interna l fault , the DTC is set .


GROUND AND POWER CONNECTIONS

GROUND CIRCUIT HIGH RESISTANCE

GROUND CIRCUIT INTERFE RENCE

CAB - INTE RNAL FAILURE


1 Inspect for non-factory wiring tha t may interfere with CAB power or ground circuits.


Inspect the CAB wiring harness for incorrect routing and damage.

Inspect the CAB harness and component connectors for corrosion and damage.

Were an y concerns found?

All



N o Go To 2



N o t e : Ch e c k c o n n e c t o r - C le a n / r e p a i r a s n e c e s s a r y .

Measure the resistance of the CAB ground circuits to body ground.

Is the resistance below 1.0 ohm?

All

Yes G o To 3

N o Repair the Ground circuit high resistance.






Turn on a ll accessories.

Measure the voltage of the Ground circuit.

Is the voltage below 1.0 volts?

All

Yes G o To 4

N o Repair as necessary. Unsplice any accessories connected to t he

CAB ground circuit. Reroute and shield any high voltage cables

away from the CAB ground circuit.


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4 If t h er e a r e n o possible ca u ses r em a in in g, view r epa ir. All

Repair

Replace the CAB.


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CONTROLLER FAILURE C o n t i n u e d

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S y m p t o m :

G-SWITCH NOT PROCESSABLE


G-SWITCH NOT PR OCESSABLE

When M onitored: Ignition on. The CAB sends a test signal out to the G-switch and

monitors the sense circuits #1 and #2.

Set Condition: If the sense circuits ar e open for 2 minu tes while driving or a n otherwise

improper signal is detected a t any time, th e Diagnostic Trouble Code (DTC) is set.


G-SWITCH TEST SIGNAL CIRCUIT OPEN

INTERMITTENT DTC

G-SWITCH TEST SIGNAL OR SENSE CIRCUIT SHORT TO VOLTAGE OR GROUND

G-SWITCH SIGNAL CIRCUIT INTERNAL OPEN

CAB - TEST SIGNAL CIRCUIT OPEN

G-SWITCH #1 SENSE CIRCUIT OPE N

G-SWITCH #1 SENSE SWITCH OPEN

CAB - #1 SENSE CIRCUIT OPEN

G-SWITCH #2 SENSE CIRCUIT OPE N

G-SWITCH #2 SENSE SWITCH OPEN

CAB - #2 SENSE CIRCUIT OPEN



With the DRBIII, read the s tatus of the G -S w itch interna l s w itches .

What is the status of both of the G-Switches?

All

Both G-Switches are closed.

G o To 2

Both G-Switches are open.

G o To 3

Only the #1 G-Switch is open.

G o To 7

Only the #2 G-Switch is open.

G o To 1 0

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Visually inspect th e r elated wire har ness connectors. Look for broken, bent, pu shedout, or corroded t ermina ls.



All



N o Test Complete.


Disconnect the CAB connector.

C h e c k c o n n e c t o r - C l e a n /r e p a i r a s n e c e s s a r y .

Disconnect the G-Switch Sensor Connector.

N O TE : C h e c k c o n n e c t o r - C l e a n / re p a i r a s n e c e s s a r y.

Measure the resistance of the G-Switch Test Signal circuit.Is the resistance below 5 ohms?

All

Yes G o To 4

N o Repair the G-Switch Test Signal Circuit Open.



Disconnect the CAB Connector.





Using a 12-volt t est light connected t o ground, check th e Test Signa l an d both Sen se

circuits.Using a 12-volt test light connected to 12-volts, check the Test Signal and both Sense

circuits.

C AU T IO N : T h e t e s t l i g h t s h o u l d n o t l i g h t a t a n y t e s t p o i n t .

D oes the tes t l ight i l lum inate at any t es t point?

All

Yes Repair the G -S w itch Tes t S ignal or S ens e circuit for a s hort to

voltage or ground.


N o Go To 5


Disconnect the G-Switch Connector.


Remove G-Switch from vehicle.While holding the G-Switch level, measure the resistance of the G-Switch Test Signal

circuit a nd the G-Switch #1 Sense circuit in th e G-Switch connector.


All

Yes G o To 6

N o Replace G-Switch.


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G-SWITCH NOT PROCESSABLE C o n t i n u e d

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Repair

Replace the CAB.




N o t e : Ch e c k c o n n e c t o r - C l e a n /r e p a i r a s n e c e s s a r y.


Measure the resistance of the G-Switch #1 Sense Circuit.


All

Yes G o To 8

N o Repair the G-Switch #1 Sense circuit open.



C h e c k c o n n e c t o r - C l e a n /r e p a i r a s n e c e s s a r y .Remove G-Switch from vehicle.

While holding the G-Switch level, measure the resistance of the G-Switch Test Signal

circuit a nd the G-Switch #1 Sense circuit in the G-Switch connector.


All

Yes G o To 9

N o Replace G-Switch Assembly.



Repair

Replace t he CAB.


1 0 Tu r n t h e i gn it i on off.



Disconnect the G-Switch Connector.


Measure the resistance of the G-Switch #2 Sense Circuit.


All

Yes G o To 11

N o Repair the G-Switch #2 Sense Circuit Open.


11 Tu r n t h e i gn i t ion off.Disconnect the G-Switch connector.


Remove the G-Switch from vehicle.

While holding the G-Switch level, measure the resistance of the G-Switch Test Signal

circuit a nd the G-Switch #2 Sense circuit in th e G-Switch connector.


All

Yes G o To 1 2

N o Replace the G-Switch Assembly.


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Repair

Replace the CAB.


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S y m p t o m L i s t :

LEFT FRONT SENSOR CIRCUIT FAILURE

LEFT REAR SEN SOR CIRCUIT FAILURE

RIGHT FRONT S ENS OR CIRCUIT FAILURE

RIGHT REAR S ENS OR CIRCUIT FAILURE

Te s t N o t e : Al l s y m p t o m s l i s t e d a b o v e a r e d i a g n o s e d u s i n g t h e s a m e te s t s .

The title for the tests will be LEFT FRONT SENSOR CIRCUIT

FAILURE.


LEFT FRONT SENSOR CIRCUIT FAILURE

When M onitored: Ignition on. The CAB m onitors the Wheel Speed Sensor circuits

continuously.

Set Condition: If the CAB detects an open or shorted wheel speed sensor circuit , the

Diagnostic Trouble Code (DTC) will set .

LEFT REAR SENSOR CIRCUIT FAILURE


continuously.



RIGHT FRONT SENSOR CIRCUIT FAILUREWhen M onitored: Ignition on. The CAB m onitors the Wheel Speed Sensor circuits

continuously.



RIGHT REAR SENSOR CIRCUIT FAILURE


continuously.

Set Condition: If the CAB detects an open or shorted Wheel speed sensor circuit , the



SENSOR OR CONNECTOR DAMAGE

INTERMITTENT DTC

WHEEL SPEED SENSOR OPEN OR SHORTED TO GROUND

WHEEL SPEED SENSOR (+) OR (-) CIRCUIT SHORTED TO VOLTAGE

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WHEEL SPEE D SE NSOR (+) OR (-) CIRCUIT SH ORTED TO GROUND

WHEEL SPEED SENSOR CIRCUITS SHORTED TOGETHER

SPEED SENSOR (+) OR (-) CIRCUIT OPEN

CAB - INTERNAL SHORT OR OPEN




With the DRBIII, era se DTCs.

Turn the ignition off.



Does the DRBIII display a Wheel Speed Sensor Circuit Failure DTC?

All

Yes G o To 2

N o Go To 9


Inspect t he a ffected Wheel Speed Sensor a nd Connector.

Is the Sensor or Connector Damaged?

All



N o Go To 3


Disconnect the affected Wheel Speed Sensor connector.


M eas ure the res is tance acros s the W heel S peed S ens or (+) and (-) circuits at theSensor side of the connector.

Measure t he resista nce between ground an d th e (+) and (-) circuits on the Sen sor side

of the connector.

Is the S ens or res istance 900 to 1300 ohm s and res istance to ground m ore tha n 15k

ohms?

All

Yes G o To 4

N o Repair t he short or replace the Wheel Speed Sensor, as n ecessary.



Disconnect the affected Wheel Speed Sensor connector.


Disconnect the CAB connector.N o t e : Ch e c k c o n n e c t o r - C le a n / r e p a i r a s n e c e s s a r y .


Measure the voltage of the Wheel Speed Sensor (+) and (-) circuits.

Is the voltage above 1 volt at either circuit?

All

Yes Repair the Wheel Speed Sensor circuit for a short to voltage.


N o Go To 5

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LEFT FRONT SENSOR CIRCUIT FAILURE C o n t i n u e d

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Disconnect the affected Wheel Speed Sen sor Connector.


M eas ure the res is tance betw een the W heel S peed S ens or (+) and (-) circuits andground.

Is t he r esistance below 15,000 ohms for either circuit?

All

Yes Repair the Wheel Speed Sensor circuit short to ground.


N o Go To 6



Disconnect the affected Wheel Speed Sen sor ha rness connector.

M eas ure th e r es is tance th rough the W heel S peed S ens or (+) and (-) circuits at the

CAB har ness connector.


All

Yes Repair the Wheel Speed Sensor circuits shorted together.


N o Go To 7


Disconnect the affected Wheel Speed Sen sor Connector.




Measure the resistance of the Wheel Speed Sensor (+) and (-) circuits.

Is the resistance below 5 ohms for both circuits?

All

Yes G o To 8

N o Repair t he Wheel Speed Sensor (+) or (-) circuit for an open.Perform ABS VERIFICATION TEST - VER 1.


Repair

Replace t he Controller Antilock Brak e in accordance w ith the






Visually inspect the related wire harness component and in-line connectors. Look for

broken, bent, pushed out, or corroded terminals.


Were any problems found?

All



N o Test Complete.

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LEFT FRONT SENSOR CIRCUIT FAILURE C o n t i n u e d

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S y m p t o m L i s t :

LEFT FRONT SENSOR SIGNAL FAILURE

LEFT REAR SEN SOR SIGNAL FAILURE

RIGHT FRONT S ENS OR S IGNAL FAILURE

RIGHT REAR S ENS OR S IGNAL FAILURE

Te s t N o t e : Al l s y m p t o m s l i s t e d a b o v e a r e d i a g n o s e d u s i n g t h e s a m e te s t s .

T he t i t l e f o r t he t e s t s w i l l be L E F T F R O N T SE N SO R SI GN A L

FAILURE.


LEFT FRONT SENSOR SIGNAL FAILURE

When M onitored: Wheel speed com parison is checked at drive off a nd continuously

thereafter.

Set Condition: If, during a n ABS stop, the CAB comma nds a ny valve solenoid on for an

extended length of t im e, a nd does not see a corresponding wheel speed change, th e

Diagnostic Trouble Code (DTC) is set. The DTC can also set if the signal is missing or

erratic.

LEFT REAR SENSOR SIGNAL FAILURE


thereafter.


extended length of t im e, a nd does not see a corresponding wheel speed change, th eDiagnostic Trouble Code (DTC) is set. The DTC can also set if the signal is missing or

erratic.

RIGHT FRONT SENSOR SIGNAL FAILURE


thereafter.




erratic.

RIGHT REAR SENSOR SIGNAL FAILURE


thereafter.




erratic.

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SPEE D SE NSOR OR CONNECTOR DAMAGED

TONE WHEEL DAMAGED

WHEEL SP EED SENSOR AIR GAP OUT OF SPECIFICATION

WHEEL BEARING EXCESS RUNOUT

WHEEL SPEE D SE NSOR INOPERATIVE

CAB - CANT READ WHE EL SP EE D SE NSOR SIGN AL

INTERMITTENT SIGNAL DTC


1 Tu r n t h e ign it ion on .Using the DRBIII, monitor all Wheel Speed Sensors while an assistant drives the

vehicle.

Slowly accelerate as straight as possible from a stop to 24 km/h (15 mph).

Note the DRBIII Wheel Speed Sensor readings.

Is one wheel speed signal zero or differing from others by m ore tha n 5 km/h (3 mph)?

All

Yes G o To 2

N o Go To 7


Inspect the Wheel Speed Sensor and Connector at the affected wheel.

Is the Sensor or Connector Damaged?

All

Yes Repair as neces s ary. The CA B m us t s ens e all four w heels a t 25

km/h (15 m ph) before it will extinguish the ABS In dicat or.


N o Go To 3


At the affected wheel, inspect the Tone Wheel for dama ged or missing teet h, cracks,

or looseness.

N o t e : T h e To n e W h e e l Te e t h s h o u l d b e p e r f e c t l y s q u a r e , n o t b e n t o r n i c k e d .

Is the Tone Wheel OK?

All

Yes G o To 4

N o Replace the Tone Wheel. The CAB must sense all four wheels at

25 km/h (15 mph ) before it will extinguish t he ABS Indicator.



Using a Feeler Gauge, measure the Wheel Speed Sensor Air Gap.

N O TE : T h e Ai r G a p s h o u l d b e c h e c k e d i n a t l e a s t f o u r p l a c e s o n t h e T o n e

Wh eel.

Is the Air Gap between 0.42 mm - 1.71 mm (0.017 - 0.068) ?

All

Yes G o To 5

N o Repair as neces s ary. The CA B m us t s ens e all four w heels a t 25

km/h (15 mph ) before it will extinguish the ABS In dicat or.


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LEFT FRONT SENSOR SIGNAL FAILURE C o n t i n u e d

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Inspect the wheel bearing for excessive runout or clearance.

N o t e : R e f e r t o t h e a p p r o p r i a t e s e r v i c e i n f o r m a t i o n , i f n e c e s s a r y , f o r p r o c e -

d u r e s o r s p e c i f i c a t i o n s .Is the bearing run out O K ?

All

Yes G o To 6

N o Repair as neces s ary. The CA B m us t s ens e all four w heels a t 25




Raise the affected wheel off the ground.

Disconnect the Wheel Speed Sensor connector a t the affected wheel.

S et up an A C voltm eter t o read t he output of the W heel S peed S ens or.

Q uickly rotate the w heel by s pinning the t ire by han d.

Measure the Wheel Speed Sensor AC voltage output.

Does the voltage go above 650 millivolts as the wheel is rotated?

All




N o Replace the Wheel Speed Sensor in accordance with the Service

Information. The CAB must sense all four wheels at 25 km/h (15

mph) before it will extinguish the ABS In dicator.



Visually inspect th e a ffected Wheel Speed Sensor for correct installat ion.

Visually inspect t he Tone Wheel for looseness and correct installat ion.

Visually inspect the wiring ha rness for loose or interm ittent connections.

Visually inspect mechan ical brake components.Inspect for conditions that may cause lockup or drag.

Inspect for seized caliper or wheel cylinder piston.

Inspect all component s for a condition which ma y cause a Wheel Speed Signal DTC

to s et.

Is any Component Damaged?

All


km/h (15 m ph) before it will extinguish the ABS In dicat or.


N o Test Complete.

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LEFT FRONT SENSOR SIGNAL FAILURE C o n t i n u e d

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S y m p t o m :

PUMP MOTOR NOT WORKING PROPERLY


PU MP MOTOR NOT WORKING PR OPERLY

When Monitored: Ignition on. The CAB comma nds th e pump on at 20 km/h (12 mph) to

check its operation, if the brake switch is not applied. If the driver has their foot on the

b r a ke , t h e t e st w ill r u n a t 4 0 k m /h (2 5 m p h ). T he C AB m on it or s p u mp volt a ge

continuously.

Set Condition: The DTC is stored when t he CAB detects: 1) Impr oper volta ge decay after

the pump was turned off. 2) Pump not energized by the CAB, but voltage is present for 3.5

seconds. 3) Pum p is t ur ned on by the CAB, but their is insufficient volta ge to operat e it.


ABS PUMP MOTOR INTERMITTENT DTC

FUSED B(+) CIRCUIT INTERMITTENTLY SHORTED TO GROUND

FUSED B(+) CIRCUIT SHORTED TO GROUND

CAB - FUSED B(+) CIRCUIT SHORTED TO GROUND

FUSE BLOWN - PUMP MOTOR CIRCUIT

NO B+ SUP PLY TO FUSE

ABS PUMP MOTOR INOPERATIVE

FUSED B(+) CIRCUIT OPEN

GROUND CIRCUIT OPE N

GROUND CIRCUIT HIGH RESISTANCE

CAB - INTERNAL FAULT







With the DRBIII, actuate the A BS pum p m otor.D id th e P um p M otor operate w hen actuated?

All

N o Go To 2

Yes G o To 1 3


Rem ove and ins pect the A BS P um p fus e in the P D C.

Is the F us e blow n?

All

Yes G o To 3

N o Go To 7

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Make sure the Pump Motor connector is secure.

Vis ually ins pect the F us ed B(+) Circuit in t he w iring ha rnes s from the P D C to the

CAB. Look for any sign of an Intermittent Short to Ground.Is the w iring har nes s O K ?

All

Yes G o To 4

N o Repair the Fused B(+) Circuit shorted to ground. The CAB must

sense all four wheels at 25 km/h (15 mph) before it will extinguish

the ABS In dicat or.



Remove ABS PUMP Fuse 8 from the Power Distribution Center (PDC).


Make sure the Pump Motor connector is secure.


Using a test light connected to 12 volts, probe the Fused B (+) Circuit.Is the t es t l ight on?

All

Yes Repair the F us ed B(+) circuit s hort to ground. The CA B m us t

sense all four wheels at 25 km/h (15 mph) before it will extinguish

the ABS Indicator.


N o Go To 5


Remove ABS PUMP Fuse 12 from the PDC.

The CAB must be connected for the results of this test to be valid.

Using a test light connected to 12 volts, probe the Fused B (+) circuit in the PDC.

Is the t es t l ight on?

All




N o Go To 6


Make sure the Pump Motor connector is secure

If there ar e no potential caus es rem a ining, replace th e F u s e.

If there are no possible causes remaining, view repair.

All

Repair

Replace th e ABS Pu mp Motor Fuse. The CAB must sense all four

w heels at 25 km /h (15 m ph) before it w ill extinguis h the A BS

Indicator.Perform ABS VERIFICATION TE ST - VER 1.

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PUMP MOTOR NOT WORKING PROPERLY C o n t i n u e d

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Remove ABS PUMP Fuse #12 from the Power Distribution Center (PDC).


N o t e : Ch e c k c o n n e c t o r - C le a n / r e p a i r a s n e c e s s a r y .M eas ure the res istance of the F u s ed B (+) circuit betw een t he P D C F us e Term inal

and the CAB connector.


All

Yes G o To 8

N o Repair the Fused B(+) circuit for an open. The CAB must sense all

four wheels at 25 km/h (15 mph) before it will extinguish the ABS

Indicator.



Using a 12-volt test light connected t o ground, check t he B+ supply to Fu se 12 in th e

PDC.

Is the B+ s upply O K ?

All

Yes G o To 9

N o Repair the B+ s upply for an open. The CAB m u s t s ens e all four

w heels at 25 km /h (15 m ph) before it w ill extinguis h the A BS

Indicator.



Disconnect Pump Motor Connector.

Connect a 10 gauge jumper wire between pump motor Fused B (+) circuit and a 40

Amp Fused B (+) circuit.

Connect a 10 gauge jumper wire between pump motor ground circuit and a known

good body ground.

Monitor Pump Motor operation.Is the pum p m otor ru nning?

All

Yes G o To 1 0

N o Replace t he Controller Antilock Brake in accordance w ith the

Service Information. The CAB must sense all four wheels at 25



1 0 Tu r n t h e i gn it i on off.

Disconnect CAB Connector.


Measure the resistance of the CAB ground circuits.


All

Yes G o To 11

N o Repair the ground circuit for an open. The CA B m us t s ens e all


Indicator.


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11 M a k e s u r e t h e P u m p M ot or con n e ct or is se cu r e .


With the DRBIII, enable pum p m otor actuation.

N O TE : P u m p m o t o r w i l l n o t o p e r a t e , b u t v o l t a g e w i l l b e a p p l i e d .Measure the voltage drop across the ABS ground circuit connection, with pump motor

actuation enabled.

Is t he voltage below 0.1 volt?

All

Yes G o To 1 2

N o Repair the G round circuit for an open. The CA B m us t s ens e all


Indicator.



Repair

Replace the Controller Anti-Lock Brake in accordance with the

S ervice Inform at ion. The CAB m us t s ens e all four w heels at 25

km/h (15 m ph) before it will extinguish th e ABS In dicator.


1 3 Tu r n t h e ig ni t ion off.



Make sure the Pump Motor connecter is secure.

Visually inspect th e relat ed wire h ar ness connectors. Look for broken, bent, pu shed

out, or corroded t ermina ls.



All


km/h (15 m ph) before it will extinguish the ABS In dicat or.Perform ABS VERIFICATION TE ST - VER 1.

N o Test Complete.

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S y m p t o m :

SYSTEM OVER VOLTAGE


SYSTEM OVER VOLTAGE

When Monitored: Ignition on. The CAB monitors t he F used B(+) circuit a t all times for


Set Condition: If the volta ge is above 16.5 volts, th e Diagnostic Trouble Code (DTC) is set.


BATTERY OVERCHARGED

FUSED IGNITION SWITCH OUTPUT HIGH



INTERMITTENT DTC






S tart the engine.

With the DRBIII

, read DTCs.Does the DRBIII display System Overvoltage DTC?

All

Yes G o To 2

N o Go To 6


Inspect for battery charger connected to battery.

Is a battery charger connected to the batt ery?

All

Yes Charge battery to proper level. D is connect the battery charger.

Clear DTCs.


N o Go To 3

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S tart the engine.Raise en gine RP Ms a bove 1,800.

M eas ure th e batt ery voltage.

Is t he voltage a bove 16.5 volts ?

All

Yes Refer to appropriate s ervice inform ation for charging s ystem

tes ting and repair.


N o Go To 4




Measure the resistance of the ground circuits.


All

Yes G o To 5

N o Repair the Ground circuit for an open.



Repair

Replace t he Contr oller Antilock Bra ke.





Visually inspect th e relat ed wire h arn ess connectors. Look for broken, bent, push ed




All



N o Test Complete.

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BRAKES (CAB)

SYSTEM OVER VOLTAGE C o n t i n u e d

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S y m p t o m :

SYSTEM UNDER VOLTAGE


SYSTEM UNDER VOLTAGE

When Monitored: Ignition on. The CAB monitors the Fused Ignition Switch Output for


Set Condition: If the volta ge is below 9.5 volts, th e Diagnostic Trouble Code (DTC) is set.


BATTERY VOLTAGE LOW

INTERMITTENT DTC

FUSED IGNITION SWITCH OUTPUT CIRCUIT H IGH RESISTANCE








S tart the engine.

Drive the vehicle above 16 km/h (10 mph) for at least 20 seconds.Stop the vehicle


Does the DRBIII display System Un dervoltage DTC?

All

Yes G o To 2

N o Go To 6

2 E ngin e Ru nn in g.

M eas ure th e batt ery voltage.

Is the battery voltage below 10 volts?

All

Yes Refer to appropriate s ervice inform ation for charging s ystem

tes ting and repair.


N o Go To 3




Measure the resistance of the ground circuits.


All

Yes G o To 4

N o Repair the Ground circuit for an open.


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4 D is con n e ct t h e C AB h a r n e s s con n e ct or .


Measure the voltage of the Fused Ignition Switch circuit.

Is the voltage above 10 volts?

All

Yes G o To 5

N o Repair the Fused Ignition Switch Output Circuit for high resis-

tance



Repair

Replace t he Contr oller Antilock Bra ke.




partially broken wires.Visually inspect th e relat ed wire h ar ness connectors. Look for broken, bent, pu shed




All



N o Test Complete.

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BRAKES (CAB)

SYSTEM UNDER VOLTAGE C o n t i n u e d

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S y m p t o m :

*ABS WARNING INDICATOR ALWAYS ON


ABS RELAY STUCK

ABS RELAY FUSED B+ CIRCUIT OPEN

ABS RELAY CONTROL CIRCUIT OPEN

CAB INTERNAL OPEN

ABS INDICATOR DRIVER SHORT TO GROUND

INSTRUMENT CLUSTER CONCERN


1 R em ov e t h e AB S r e la y fr om P D C.Perform the key-on bulb test.

Does the ABS Indicator light and remain lit?

All

Yes G o To 2

N o Go To 3

2 D is con n e ct t h e I n s t r u m e n t C lu s t e r C 2 h a r n e s s con n e ct or .

Remove the ABS relay from the PDC.

Using a 12-volt test light connected to 12-volts, check the ABS Warning Indicator

Driver circuit.

Does the test light illuminate?

All

Yes Repair the ABS Indicator circuit for a short to ground. The CAB

may have to sense all four wheels at 25 km/h (15 mph) before itwill extinguish the ABS Indicator.


N o Refer to symptom list for pr oblems related t o Instru ment Cluster.

The CAB may have to sense all four wheels at 25 km/h (15 mph)

before it will extinguish the ABS Indicator.


3 I n s t a ll a s u bs t it u t e r el a y i n p la ce of t h e AB S r e la y.

Perform the key-on bulb check.

Does t he ABS Warn ing Indicator operat e OK?

All

Yes Replace th e A

Documents

2005 Tj Chassis