steering wheel CHRYSLER VOYAGER 1996 Owner's Guide

ADJUSTER REAR DRUM BRAKE (AUTOMATIC)
The rear drum brakes on this vehicle automatically
adjust, when required, during the normal operation
of the vehicle every time the brakes are applied. Use
the following procedure to test the operation of the
automatic adjuster.
Place the vehicle on a hoist with a helper in the
driver's seat to apply the brakes. Remove the access
plug from the adjustment hole in each brake support
plate to provide visual access of the brake adjuster
star wheel.
Remove the park brake cable, for the wheel of the
vehicle that is being worked on, from the park brake
cable equalizer (Fig. 12). This is required to gain
access to the star wheel. If the cable is not removed
from the equalizer, the cable and spring inside of the
brake drum is in the way of the star wheel.
To eliminate the condition where maximum adjust-
ment of the rear brake shoes, does not allow the
automatic adjuster to operate when tested, back the
star wheel off approximately 30 notches. It will be
necessary to hold the adjuster lever away from the
star wheel to permit this adjustment.
Have the helper apply the brakes. Upon applica-
tion of the brake pedal, the adjuster lever lever
should move down, turning the adjuster star wheel.
Thus, a definite rotation of the adjuster star wheel
can be observed if the automatic adjuster is working
properly. If one or more adjusters do not function
properly, the respective drum must be removed for
adjuster servicing.
BRAKE ROTOR
Any servicing of the rotor requires extreme care to
maintain the rotor to within service tolerances to
ensure proper brake action.Before refinishing or refacing a rotor, the rotor
should be checked and inspected for the following
conditions:
Braking surface scoring, rust, impregnation of lin-
ing material and worn ridges.
Excessive rotor lateral runout or wobble.
Thickness variation in braking surface of the rotor
(Parallelism).
Dishing or distortion in braking surface of the
rotor (Flatness).
If a vehicle has not been driven for a period of
time, the rotors will rust in the area not covered by
the brake lining and cause noise and chatter when
the brakes are applied.
Excessive wear and scoring of the rotor can cause
temporary improper lining contact if ridges are not
removed from braking surface of rotor before instal-
lation of new brake shoe assemblies.
Some discoloration and/or wear of the rotor surface
is normal and does not require resurfacing when lin-
ings are replaced.
Excessive runout or wobble in a rotor can increase
pedal travel due to piston knock-back. This will also
increase guide pin bushing wear due to the tendency
of the caliper to follow rotor wobble.
Thickness variation in a rotor can also result in
pedal pulsation, chatter and surge due to variation in
brake output. This can also be caused by excessive
runout in the rotor and/or the hub.
Dishing or distortion can be caused by extreme
heat and abuse of the brakes.
CHECKING ROTOR FOR RUNOUT AND
THICKNESS
NOTE: The procedure for checking rotor runout
and thickness is the same for the front and rear
rotor. If there is a specification difference between
the front and rear rotor it will be designated as
such in the specifications of the following proce-
dure.
On-vehicle rotor runout is the combination of the
individual runout of the hub face and the runout of
the rotor. (The hub and rotor runouts are separable).
To measure runout on the vehicle, remove the wheel
and reinstall the lug nuts tightening the rotor to the
hub. Mount Dial Indicator, Special Tool C-3339 with
Mounting Adaptor, Special Tool SP- 1910 on steering
arm. Dial indicator plunger should contact braking
surface of rotor approximately 10 mm (0.393 in.)
from outer edge of rotor (Fig. 13). Check lateral
runout on both sides of rotor. Lateral runout of the
rotor should not exceed 0.13 mm (0.005 inch).
If lateral runout is in excess of the specification,
check the lateral runout of the hub face. Before
removing rotor from hub, make a chalk mark across
Fig. 12 Park Brake Cable Equlizer
5 - 14 BRAKESNS
DIAGNOSIS AND TESTING (Continued)

both the rotor and one wheel stud on the high side of
the runout. This will ensure that the original location
of the rotor in relation to the hub can be retained
(Fig. 14). Remove rotor from hub.
Thoroughly clean the front surface of the front
hub. Then install Dial Indicator, Special Tool C-3339
and Mounting Adaptor, Special Tool SP-1910 on
steering knuckle. Position stem so it contacts hub
face near outer diameter. Care must be taken to posi-
tion stem outside the stud circle but inside the cham-
fer on the hub face (Fig. 15).Clean hub surface
before checking.
Lateral runout should not exceed 0.08 mm (0.003
inch). If runout exceeds this specification, the hub
must be replaced. See Suspension Group 2. If lateral
runout of the hub does not exceed this specification,
install rotor on hub with chalk marks two wheel
studs apart (Fig. 16). Tighten nuts in the properse-
quence and torque to specification. Finally, check lat-eral runout of rotor to see if lateral runout is now
within specification.
If lateral runout is not within specification, install
a new rotor or reface rotor, being careful to remove
as little rotor material as possible from each side of
rotor. Remove equal amounts from each side of rotor.
Do not reduce thickness below minimum thickness
marking cast into the un-machined surface (Fig. 17)
of the rotor .
Thickness variation measurements of the rotor
should be made in conjunction with the lateral
runout measurements. Measure the thickness of the
rotor at 12 circumferentially equal points with a
Fig. 16 Indexing Rotor And Wheel Stud
Fig. 13 Checking Brake Rotor For Runout
Fig. 14 Marking Rotor And Wheel Stud
Fig. 15 Checking Disc Brake Rotor For Runout
NSBRAKES 5 - 15
DIAGNOSIS AND TESTING (Continued)

SERVICE PROCEDURES
MASTER CYLINDER FLUID LEVEL CHECK
Check master cylinder reservoir fluid level a mini-
mum of twice annually.
Master cylinder reservoirs are marked with the
words FULL and ADD to indicate proper brake fluid
fill level of the master cylinder (Fig. 26).
If necessary, add brake fluid to bring the level to
the bottom of the FULL mark on the side of the mas-
ter cylinder fluid reservoir.When filling master
cylinder fluid reservoir do not fill the filler
neck of the fluid reservoir (Fig. 26) with brake
fluid.
Use only Mopartbrake fluid or an equivalent from
a sealed container. Brake fluid must conform to DOT
3, specifications.
DO NOTuse brake fluid with a lower boiling
point, as brake failure could result during prolonged
hard braking.
Use only brake fluid that was stored in a tightly-
sealed container.
DO NOTuse petroleum-based fluid because seal
damage will result. Petroleum based fluids would be
items such as engine oil, transmission fluid, power
steering fluid ect.
BLEEDING BASE BRAKE HYDRAULIC SYSTEM
NOTE: This bleeding procedure is only for the vehi-
cle's base brakes hydraulic system. For bleeding
the antilock brakes hydraulic system, refer to the
ITT Teves Mark 20 Antilock Brake System bleeding
procedure in the antilock brakes section of this ser-
vice manual.
PRESSURE BLEEDING PROCEDURE
CAUTION: Before removing the master cylinder
cover, throughly clean the cover and master cylin-
der fluid reservoir to prevent dirt and other foreign
matter from dropping into the master cylinder fluid
reservoir.
CAUTION: Use bleeder tank Special Tool C-3496-B
with adapter Special Tool 6921 to pressurize the
hydraulic system for bleeding.
CAUTION: When pressure bleeding the brakes
hydraulic system the fluid reservoir filler neck must
be removed from the master cylinder fluid reservoir.
Failure to remove the filler neck from the fluid res-
ervoir, may result in the filler neck separating from
the fluid reservoir when the hydraulic system is
pressurized.
Follow pressure bleeder manufacturer's instruc-
tions, for use of pressure bleeding equipment.
When bleeding the brake system, some air may be
trapped in the brake lines or valves far upstream, as
much as ten feet from the bleeder screw (Fig. 27).
Therefore, it is essential to have a fast flow of a large
volume of brake fluid when bleeding the brakes to
ensure all the air gets out.
(1) Remove the filler neck from the master cylin-
der fluid reservoir.
(2) Install the Adapter Master Cylinder Pressure
Bleed Cap, Special Tool 6921 on the fluid reservoir of
the master cylinder (Fig. 28). Attach the fluid hose
from the pressure bleeder to the fitting on Special
Tool 6921.
(3) Attach a clear plastic hose to the bleeder screw
at one wheel and feed the hose into a clear jar con-
taining fresh brake fluid.
Fig. 26 Master Cylinder Fluid Level Marks
Fig. 27 Trapped Air In Brake Fluid Line
5 - 20 BRAKESNS

(3) Remove the 2 caliper to steering knuckle guide
pin bolts (Fig. 44).
(4) Remove caliper from steering knuckle, by first
rotating free end of caliper away from steering
knuckle. Then slide opposite end of caliper out from
under machined abutment on steering knuckle (Fig.
45).
(5) Support caliper firmly to prevent weight of cal-
iper from being supported by the brake fluid flex
hose. Supporting weight of caliper by the brake fluid
flex hose, can damage the flexible brake hose (Fig.
46).
INSTALL
(1) Lubricate both steering knuckle abutments
with a liberal amount of MopartMultipurpose Lubri-
cant, or equivalent.CAUTION: Use care when installing the caliper
assembly onto the steering knuckle, so the seals on
the caliper guide pin bushings do not get damaged
by the steering knuckle bosses.
(2) Carefully position caliper and brake pad
assemblies over brake rotor by hooking lower or
upper end of caliper over the machined abutment on
steering knuckle (Fig. 45). Then rotate caliper into
position at the top of the steering knuckle (Fig. 45).
Make sure that caliper guide pin bolts, bushings and
sleeves are clear of the steering knuckle bosses.
(3) Install the caliper guide pin bolts (Fig. 44) and
tighten to a torque of 41 N´m (40 ft. lbs.).Extreme
caution should be taken not to cross thread the
caliper guide pin bolts.
(4) Install the wheel and tire assembly.
(5) Using a torque wrench, tighten the wheel
mounting stud nuts in proper sequence until all nuts
are torqued to half specification. Then repeat the
tightening sequence to the full specified torque of 135
N´m (100 ft. lbs.).
(6) Remove jackstands or lower hoist.
(7)Before moving vehicle, pump the brake
pedal several times to insure the vehicle has a
firm brake pedal.
REAR DISC BRAKE CALIPER
During service procedures, grease or any other for-
eign material must be kept off brake shoe assem-
blies, and braking surfaces of rotor.
Handling of the rotor and caliper, must be done in
such a way as to avoid damage to the rotor and
scratching or nicking of lining on the brake shoes.
If inspection reveals that the caliper piston seal is
leaking, itMUSTbe replaced immediately.
During removal and installation of a wheel and
tire assembly, use care not to strike the caliper.
Fig. 44 Removing Caliper Guide Pin Bolts
Fig. 45 Caliper Assembly Mounting On Steering
Knuckle (Typical)
Fig. 46 Storing Front Disc Brake Caliper
5 - 28 BRAKESNS
REMOVAL AND INSTALLATION (Continued)

(13) Lower the vehicle to the ground.Be sure
that the suspension is supporting the full
weight of the vehicle.
(14) Tighten the spring to front hanger pivot bolts
to a torque of 156 N´m (115 ft. lbs.).
(15) Tighten the shock absorber mounting bolts to
a torque of 101 N´m (75 ft. lbs.).
(16) Tighten the track bar mounting bolt to a
torque of 95 N´m (70 ft. lbs.).
(17) Road test vehicle to ensure that the prema-
ture rear wheel lockup condition has been corrected.
SPECIFICATIONS
BRAKE FLUID
The brake fluid used in this vehicle must conform
to DOT 3 specifications and SAE J1703 standards.No other type of brake fluid is recommended or
approved for usage in the vehicle brake system. Use
only Mopar brake fluid or an equivalent from a
tightly sealed container.
CAUTION: Never use reclaimed brake fluid or fluid
from an container which has been left open. An
open container will absorb moisture from the air
and contaminate the fluid.
CAUTION: Never use any type of a petroleum-
based fluid in the brake hydraulic system. Use of
such type fluids will result in seal damage of the
vehicle brake hydraulic system causing a failure of
the vehicle brake system. Petroleum based fluids
would be items such as engine oil, transmission
fluid, power steering fluid ect.
VEHICLE BRAKE SYSTEM COMPONENT SPECIFICATIONS
Brake System Component Specifications
5 - 82 BRAKESNS
ADJUSTMENTS (Continued)

BRAKE ACTUATION SYSTEM
ACTUATION:
Vacuum Operated Power Brakes.........Standard
Hydraulic System...........Dual-Diagonally Split
Antilock Brake Sytem (Teves Mark-20)...........
MASTER CYLINDER ASSEMBLY:
Supplier..............................Bosch
Type For Non-ABSAnd
ABS Brakes. . . .Conventional Compensating Port
Type For ABS Brakes
With Traction Control . . .Dual Center Port Design
Body Material...............Anodized Aluminum
Reservoir Material................Polypropelene
MASTER CYLINDER BORE /
STROKE AND SPLIT:
ABS W/Disc/Drum Brakes......23.8 mm x 36 mm
(.937 in. x 1.47 in.)
AWD W/Disc/Disc Brakes........25.4 mm x 39 mm
(1.00 in. x 1.50 in.)
Displacement Split.....................50/50
MASTER CYLINDER FLUID OUTLET PORTS:
Non-ABS And ABS . . .Primary 7/16±24 Secondary 7/
16±24
ABS With Traction Control.......Primary M12 x 1
Secondary M12 x 1
Outlet Fitting Type Non-ABS
AndABS...........Double Wall Inverted Flare
Outlet Fitting Type ABS With
Traction Control...................ISO Flare
ABS HYDRAULIC CONTROL UNIT:
Hydraulic Tube Fitting Type............ISO Flare
BOOSTER:
Make/Type.................Bosch Vacuum Assist
Mounting Studs.....................M8x1.25
Type .........................270 ZLT RSMV
Boost At 20 inches Of
Manifold Vacuum...........3800 N´m (850 lbs.)
PROPORTIONING VALVE:
Material...........................Aluminum
Function....................Hydraulic Pressure
Proportioning To Rear Brakes
BRAKE PEDAL
Pedal Ratio.............................3.36
BRAKE FASTENER TORQUE SPECIFICATIONS
DESCRIPTION TORQUE
BRAKE TUBES:
Tube Nuts To Fittings And
Components..............17N´m(145 in. lbs.)
BRAKE HOSE:
To Caliper Banjo Bolt..........48N´m(35ft.lbs.)
Intermediate Bracket.........12N´m(105 in. lbs.)
MASTER CYLINDER:
To Vacuum Booster
Mounting Nut............25N´m(225 in. lbs.)
FIXED PROPORTIONING VALVE:
To Frame Rail Attaching
Bolts....................14N´m(125 in. lbs.)
HEIGHT SENSING PROPORTIONING VALVE:
To Mounting Bracket
Attaching Bolts...........23N´m(200 in. lbs.)
Actuator Assembly
Adjustment Nut.............5N´m(45in.lbs.)
Mounting Bracket To Frame
Rail Bolts................17N´m(150 in. lbs.)
JUNCTION BLOCK (NON-ABS BRAKES)
To Suspension Cradle
Mounting Bolt............28N´m(250 in. lbs.)
VACUUM BOOSTER:
To Dash Panel Mounting
Nuts....................28N´m(250 in. lbs.)
REAR WHEEL CYLINDER:
To Support Plate Mounting
Bolts.....................8N´m(75in.lbs.)
Bleeder Screw...............10N´m(80in.lbs.)
BRAKE SUPPORT PLATE:
To Rear Axle Mounting Bolts . . .130 N´m (95 ft. lbs.)
DISC BRAKE CALIPER:
Guide Pin Bolts..............41N´m(30ft.lbs.)
Bleeder Screw..............15N´m(125 in. lbs.)
ABS HYDRAULIC CONTROL UNIT:
Mounting Bracket To
Suspension Cradle Bolts.....28N´m(250 in. lbs.)
To Mounting Bracket Isolator
Attaching Bolts............11N´m(97in.lbs.)
CAB To HCU Mounting Screws . . .2 N´m (17 in. lbs.)
WHEEL SPEED SENSOR:
To Axle Or Steering Knuckle
Mounting Bolt............12N´m(105 in. lbs.)
PARKING BRAKE:
Pedal Assembly Mounting
Bolts....................28N´m(250 in. lbs.)
REAR HUB AND BEARING:
To Axle Mounting Bolts........129 N´m (95 ft. lbs.)
WHEEL:
Stud Lug Nut........115±156 N´m (84-115 ft. lbs.)
NSBRAKES 5 - 83
SPECIFICATIONS (Continued)

ANTILOCK BRAKE SYSTEM ± TEVES MARK-20
INDEX
page page
DESCRIPTION AND OPERATION
ABS BRAKE SYSTEM COMPONENTS........ 87
ABS BRAKES COMPONENT
ABBREVIATION LIST.................... 85
ABS BRAKES OPERATION AND VEHICLE
PERFORMANCE....................... 86
ABS FUSES............................ 89
ABS MASTER CYLINDER AND POWER
BRAKE BOOSTER..................... 87
ABS RELAYS........................... 89
ABS WARNING LAMP (YELLOW)............ 91
ANTILOCK BRAKES OPERATION
DESCRIPTION........................ 85
ASR VALVE (ABS WITH TRACTION
CONTROL ONLY)...................... 88
CONTROLLER ANTILOCK BRAKES (CAB)..... 90
HCU BRAKE FLUID ACCUMULATORS AND
NOISE DAMPING CHAMBER............. 88
HCU PUMP/MOTOR..................... 89
HYDRAULIC CIRCUITS AND VALVE
OPERATION.......................... 92
INLET VALVES AND SOLENOIDS............ 88
INTEGRATED CONTROL UNIT (ICU)......... 87
OUTLET VALVES AND SOLENOIDS.......... 88
PROPORTIONING VALVES................ 89
WHEEL SPEED SENSORS................. 89
DIAGNOSIS AND TESTING
ABS BRAKE DIAGNOSTIC TOOL
CONNECTOR......................... 96
ABS DIAGNOSTIC TROUBLE CODES........ 97
ABS DIAGNOSTICS MANUAL.............. 96ABS GENERAL DIAGNOSTICS
INFORMATION........................ 95
ABS SERVICE PRECAUTIONS.............. 99
ABS SYSTEM SELF DIAGNOSTICS.......... 96
ABS WIRING DIAGRAM INFORMATION....... 95
BRAKE FLUID CONTAMINATION............ 98
DRB DIAGNOSTIC SCAN TOOL USAGE...... 96
INTERMITTENT DIAGNOSTIC TROUBLE
CODES.............................. 97
PROPORTIONING VALVE................. 98
TEST DRIVING ABS COMPLAINT VEHICLE.... 98
TONEWHEEL INSPECTION................ 98
SERVICE PROCEDURES
BLEEDING TEVES MARK 20 HYDRAULIC
SYSTEM............................. 99
BRAKE FLUID LEVEL INSPECTION.......... 99
REMOVAL AND INSTALLATION
ABS GENERAL SERVICE PRECAUTIONS.... 100
CONTROLLER ANTILOCK BRAKES (CAB).... 103
HYDRAULIC CONTROL UNIT.............. 100
TONE WHEEL (REAR AWD)............... 111
TONE WHEEL (REAR FWD)............... 110
WHEEL SPEED SENSOR (FRONT)......... 105
WHEEL SPEED SENSOR (REAR AWD)...... 108
WHEEL SPEED SENSOR (REAR FWD)...... 106
SPECIFICATIONS
BRAKE FASTENER TORQUE
SPECIFICATIONS..................... 112
SPEED SENSOR TONE WHEEL RUNOUT.... 112
WHEEL SPEED SENSOR TO TONE
WHEEL CLEARANCE.................. 112
DESCRIPTION AND OPERATION
ANTILOCK BRAKES OPERATION DESCRIPTION
The purpose of an Antilock Brake System (ABS) is to
prevent wheel lock-up under braking conditions on virtu-
ally any type of road surface. Antilock Braking is desirable
because a vehicle which is stopped without locking the
wheels will retain directional stability and some steering
capability. This allows the driver to retain greater control
of the vehicle during braking.
This section of the service manual covers the description
and on car service for the ITT Teves Mark 20 ABS Brake
System and the ITT Teves Mark 20 ABS Brake System
with Traction Control. If other service is required on the
non ABS related components of the brake system, refer to
the appropriate section in this group of the service manual
for the specific service procedure required.
ABS BRAKES COMPONENT ABBREVIATION LIST
In this section of the service manual, several
abbreviations are used for the components of the
Teves Mark 20 ABS Brake System and the Teves
Mark 20 ABS Brake System with Traction Control.
They are listed below for your reference.
²CAB±Controller Antilock Brake
²ICU±Integrated Control Unit
²HCU±Hydraulic Control Unit
²TCS±Traction Control
²ABS±Antilock Brake System
²PSI±Pounds Per Square Inch (pressure)
²WSS±Wheel Speed Sensor
²FWD±Front Wheel Drive
²AWD±All Wheel Drive
²DTC±Diagnostic Trouble Code
NSBRAKES 5 - 85

ABS BRAKES OPERATION AND VEHICLE
PERFORMANCE
This ABS System represents the current state-of-
the-art in vehicle braking systems and offers the
driver increased safety and control during braking.
This is accomplished by a sophisticated system of
electrical and hydraulic components. As a result,
there are a few performance characteristics that may
at first seem different but should be considered nor-
mal. These characteristics are discussed below.
NORMAL BRAKING SYSTEM FUNCTION
Under normal braking conditions, the ABS System
functions the same as a standard brake system with
a diagonally split master cylinder and conventional
vacuum assist.
ABS SYSTEM OPERATION
If a wheel locking tendency is detected during a
brake application, the brake system will enter the
ABS mode. During ABS braking, hydraulic pressure
in the four wheel circuits is modulated to prevent
any wheel from locking. Each wheel circuit is
designed with a set of electric solenoids to allow mod-
ulation, although for vehicle stability, both rear
wheel solenoids receive the same electrical signal.
During an ABS stop, the brakes hydraulic system
is still diagonally split. However, the brake system
pressure is further split into four control channels.
During antilock operation of the vehicle's brake sys-
tem the front wheels are controlled independently
and are on two separate control channels and the
rear wheels of the vehicle are controlled together.
The system can build and release pressure at each
wheel, depending on signals generated by the wheel
speed sensors (WSS) at each wheel and received at
the Controller Antilock Brake (CAB).
ABS operation is available at all vehicle speeds
above 3 to 5 mph. Wheel lockup may be perceived at
the very end of an ABS stop and is considered nor-
mal.
VEHICLE HANDLING PERFORMANCE DURING
ABS BRAKING
It is important to remember that an antilock brake
system does not shorten a vehicle's stopping distance
under all driving conditions, but does provide
improved control of the vehicle while stopping. Vehi-
cle stopping distance is still dependent on vehicle
speed, weight, tires, road surfaces and other factors.
Though ABS provides the driver with some steer-
ing control during hard braking, there are conditions
however, where the system does not provide any ben-
efit. In particular, hydroplaning is still possible when
the tires ride on a film of water. This results in the
vehicles tires leaving the road surface rendering the
vehicle virtually uncontrollable. In addition, extremesteering maneuvers at high speed or high speed cor-
nering beyond the limits of tire adhesion to the road
surface may cause vehicle skidding, independent of
vehicle braking. For this reason, the ABS system is
termed Antilock instead of Anti-Skid.
NOISE AND BRAKE PEDAL FEEL
During ABS braking, some brake pedal movement
may be felt. In addition, ABS braking will create
ticking, popping and/or groaning noises heard by the
driver. This is normal due to pressurized fluid being
transferred between the master cylinder and the
brakes. If ABS operation occurs during hard braking,
some pulsation may be felt in the vehicle body due to
fore and aft movement of the suspension as brake
pressures are modulated.
At the end of an ABS stop, ABS will be turned off
when the vehicle is slowed to a speed of 3±4 mph.
There may be a slight brake pedal drop anytime that
the ABS is deactivated, such as at the end of the stop
when the vehicle speed is less then 3 mph or during
an ABS stop where ABS is no longer required. These
conditions will exist when a vehicle is being stopped
on a road surface with patches of ice, loose gravel or
sand on it. Also stopping a vehicle on a bumpy road
surface will activate ABS because of the wheel hop
caused by the bumps.
TIRE NOISE AND MARKS
Although the ABS system prevents complete wheel
lock-up, some wheel slip is desired in order to
achieve optimum braking performance. Wheel slip is
defined as follows, 0 percent slip means the wheel is
rolling freely and 100 percent slip means the wheel is
fully locked. During brake pressure modulation,
wheel slip is allowed to reach up to 25 to30%. This
means that the wheel rolling velocity is 25 to 30%
less than that of a free rolling wheel at a given vehi-
cle speed. This slip may result in some tire chirping,
depending on the road surface. This sound should not
be interpreted as total wheel lock-up.
Complete wheel lock up normally leaves black tire
marks on dry pavement. The ABS System will not
leave dark black tire marks since the wheel never
reaches a fully locked condition. Tire marks may
however be noticeable as light patched marks.
START UP CYCLE
When the ignition is turned on, a popping sound
and a slight brake pedal movement may be noticed.
Additionally, when the vehicle is first driven off a
humming may be heard and/or felt by the driver at
approximately 20 to 40 kph (12 to 25 mph). The ABS
warning lamp will also be on for up to 5 seconds
after the ignition is turned on. All of these conditions
are a normal function of ABS as the system is per-
forming a diagnosis check.
5 - 86 BRAKESNS
DESCRIPTION AND OPERATION (Continued)

PREMATURE ABS CYCLING
NOTE: When working on a vehicle which has a
complaint of premature ABS cycling it may be nec-
essary to use a DRB Scan Tool to detect and verify
the condition.
There is one complaint called Premature ABS
Cycling in which neither the Red Brake Warning
Lamp nor the Amber Antilock Lamp were illumi-
nated and no fault codes were stored in the CAB.
Symptoms of Premature ABS Cycling, include click-
ing sounds from the solenoids valves, pump motor
running and pulsations in the brake pedal. This con-
dition can occur at any braking rate of the vehicle
and on any type of road surface. This creates an
additional condition which needs to be correctly
assessed when diagnosing problems with the antilock
brake system.
The following conditions are common causes that
need to be checked when diagnosing a condition of
Premature ABS Cycling. Damaged tone wheels,
incorrect tone wheels, damage to a wheel speed sen-
sor mounting boss on a steering knuckle, a loose
wheel speed sensor mounting bolt, and excessive tone
wheel runout. Also, an excessively large tone wheel
to wheel speed sensor air gap can lead to the condi-
tion of Premature ABS Cycling. Special attention is
to be given to these components when diagnosing a
vehicle exhibiting the condition of Premature ABS
Cycling. After diagnosing the defective component,
repair or replace as required.
When the component repair or replacement is com-
pleted, test drive the vehicle to verify the condition of
Premature ABS Cycling has been corrected.
ABS BRAKE SYSTEM COMPONENTS
The following is a detailed description of the Teves
Mark 20 ABS brake system components. For infor-
mation on servicing the base brake system compo-
nents, see the base Brake System section of this
Service Manual.
ABS MASTER CYLINDER AND POWER BRAKE
BOOSTER
A vehicle equipped with Teves Mark 20 ABS
without optional traction control uses the same
type of a master cylinder and power brake
booster (Fig. 1) as a vehicle not equipped with
antilock brakes.
A vehicle equipped with Teves Mark 20 ABS
with Traction control uses a unique center port
master cylinder. If the master cylinder is
replaced on a vehicle equipped with traction
control be sure the right type of master cylin-
der is installed.A vehicle equipped with four wheel disc
brakes (AWD applications) also have a unique
master cylinder. The master cylinder used on
these vehicles have a piston bore diameter
which is larger then the master cylinder used
on the other brake applications.
The primary and secondary outlet ports on the
master cylinder go directly to the hydraulic control
unit HCU.
Reference the appropriate section of this service
manual for further information on the individual
components.
INTEGRATED CONTROL UNIT (ICU)
The hydraulic control unit (HCU) (Fig. 2) used
with the Teves Mark 20 ABS is different from the
HCU used on previous Chrysler products with ABS.
The HCU used on this ABS system is part of the
integrated contol unit (ICU). The HCU is part of
what is referred to as the ICU because the HCU and
the controller antilock brakes (CAB) are combined
(integrated) into one unit. This differs from previous
Chrysler products with ABS, where the HCU and the
CAB were separate components located in different
areas of the vehicle.
Teves Mark 20 ABS uses two different HCU's and
CAB's depending on the type of ABS system the vehi-
cle is equipped with. There is a unique HCU and
CAB for a vehicle equipped with just ABS and a
unique HCU and CAB for a vehicle equipped with
ABS and traction control.
NOTE: The HCU and CAB used on a vehicle that is
equipped with only ABS and on a vehicle that is
equipped with ABS and traction control are differ-
ent. The HCU on a vehicle equipped with ABS and
traction control has a valve block housing (Fig. 2)
that is approximately 1 inch longer on the low pres-
sure fluid accumulators side than a HCU for a vehi-
cle that is equipped with only ABS.
Fig. 1 Master Cylinder And Vacuum Booster
NSBRAKES 5 - 87
DESCRIPTION AND OPERATION (Continued)

The front wheel speed sensor is attached to a boss
in the steering knuckle (Fig. 7). The front tone wheel
(Fig. 7) is part of the driveshafts outboard constant
velocity joint. The rear wheel speed sensor ismounted through the rear axle, rear brake support
plate and directly to the rear bearing (Fig. 8) (Fig. 9).
The rear tone wheel on a front wheel drive vehicle is
an integral part of the rear wheel hub/bearing
assembly. If damaged though, the rear tone wheel on
a front wheel drive vehicle can be replaced as a indi-
vidual component of the rear hub/bearing assembly.
Refer to Rear Tone Wheel in the Remove And Install
Section in this group of the service manual for the
required procedure. The wheel speed sensor air gap
is NOT adjustable.
The rear tone wheel on a all wheel drive vehicle, is
part of the outboard constant velocity joint on the
rear driveshaft (Fig. 9).
The four wheel speed sensors are all serviced indi-
vidually, but the front tone wheel on all vehicles and
the rear tone wheel on all wheel drive vehicles are
serviced as part of the front or rear driveshaft out-
board constant velocity joint (Fig. 7) and (Fig. 9).
Correct ABS system operation is dependent on
accurate wheel speed signals. The vehicle's wheels
and tires must all be the same size and type to gen-
erate accurate signals. Variations in wheel and tire
size can produce inaccurate wheel speed signals,
which can cause false ABS cycles to occur.
CONTROLLER ANTILOCK BRAKES (CAB)
The Controller Antilock Brakes (CAB) is a micro-
processor based device which monitors the ABS sys-
tem during normal braking and controls it when the
vehicle is in an ABS stop. The CAB is mounted to the
bottom of the HCU (Fig. 10). The CAB uses a 25 way
electrical connector on the vehicle wiring harness.
The power source for the CAB is through the ignition
switch in the Run or On position.THE (CAB) IS ON
THE CCD BUS
Fig. 6 Proportioning Valve Mounting Location
Fig. 7 Front Wheel Speed Sensor
Fig. 8 Rear Wheel Speed Sensor (FWD)
Fig. 9 Rear Wheel Speed Sensor (AWD)
5 - 90 BRAKESNS
DESCRIPTION AND OPERATION (Continued)