2002 CHRYSLER CARAVAN shaft

(1) Connect the front wheel speed sensor cable to
the vehicle wiring harness connector. Be sure speed
sensor cable connector is fully seated and locked into
vehicle wiring harness connector.
(2) Install the bolts attaching the routing clamps
to the body of the vehicle. Tighten the bolts to a
torque of 14 N´m (125 in. lbs.).
(3) Insert speed sensor cable grommets into inter-
mediate bracket on strut.
(4) Install the wheel speed sensor head mounting
bolt (Fig. 1). Tighten the bolt to a torque of 13 N´m
(115 in. lbs.)
(5) Install the wheel and tire assembly on vehicle.
(6) Lower vehicle.
(7) Road test vehicle to ensure proper operation of
the base and ABS brake systems.
REAR WHEEL SPEED SENSOR
-AWD
REMOVAL
(1) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
CAUTION: When disconnecting speed sensor cable
from vehicle wiring harness be careful not to dam-
age pins on the electrical connectors. Also, inspect
connectors for any signs of previous damage.(2) Remove grommet from floor pan of vehicle and
disconnect speed sensor cable connector from vehicle
wiring harness.
CAUTION: When removing rear wheel speed sensor
cable from routing clips, be sure not to damage the
routing clips. Routing clips that are molded onto
the brake hose will require replacement of the brake
hose if damaged during removal or installation of
the speed sensor cable.
(3) Carefully remove speed sensor cable from
press-in routing clips along brake hose and tubing.
(4) Remove bolt securing wheel speed sensor cable
metal clip to rear of axle. Remove metal clip from
cable if necessary.
CAUTION: If speed sensor head has seized due to
corrosion, do not use pliers on speed sensor head
in an attempt to remove it. Use a hammer and a
punch and tap mounting flange edge side-to-side,
rocking the sensor until free.
(5) Remove wheel speed sensor head attaching
bolt.
(6) Remove wheel speed sensor head from the axle,
and remove sensor from vehicle.
INSTALLATION
CAUTION: Proper installation of wheel speed sen-
sor cables is critical to continued system operation.
Be sure that cables are installed in retainers. Fail-
ure to install cables in retainers as indicated may
result in contact with moving parts or over-exten-
sion of cables, resulting in an open circuit.
(1) Install wheel speed sensor head in axle flange.
CAUTION: Prior to installing the speed sensor head
attaching bolt, the plastic anti-rotation pin must be
fully seated into the bearing flange.
(2) Install wheel speed sensor head attaching bolt.
Tighten bolt to a torque 10 N´m (90 in. lbs.).
(3) Check the air gap between the face of the
wheel speed sensor and the top surface of the tone
wheel. (Refer to 5 - BRAKES - SPECIFICATIONS)
CAUTION: When installing wheel speed sensor
cable in the routing clips on rear brake flex hose,
be sure not to damage the routing clips. Routing
clips are molded onto the hose and will require
replacement of the brake hose if damaged.
(4) Install speed sensor cable under leaf spring
onto brake hose and tubing utilizing routing clips to
secure it in place.
Fig. 1 Front Wheel Speed Sensor Attaching Bolt
1 - MOUNTING BOLT
2 - WHEEL SPEED SENSOR
3 - DRIVESHAFT
4 - TONE WHEEL
5 - STEERING KNUCKLE
5 - 90 BRAKES - ABSRS
FRONT WHEEL SPEED SENSOR (Continued)
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(2) Install wheel speed sensor head into rear of
hub and bearing aligning index tab with the notch in
the top of the mounting hole. Push the sensor in
until it snaps into place on the metal retaining clip.
(3) Install secondary (yellow) retaining clip over
wheel speed sensor head and engage the tabs on each
side.
(4) Route sensor cable under leaf spring along rear
of axle. Install speed sensor cable into routing clips
on rear brake flex hose (Fig. 3).
(5) Install cable into metal routing clip and attach
it to the rear axle with mounting bolt (Fig. 3).
Tighten mounting bolt to 16 N´m (140 in. lbs.).
(6) Connect wheel speed sensor cable to vehicle
wiring harness (Fig. 2).Be sure speed sensor
cable connector is fully seated and locked into
vehicle wiring harness connector.
(7) Install speed sensor cable grommet into hole in
floor pan making sure grommet is fully seated into
hole.
(8) Lower vehicle.
(9) Road test vehicle to ensure proper operation of
the base and ABS braking systems.
TONE WHEEL
INSPECTION - TONE WHEEL
NOTE: Rear tone wheels for front-wheel-drive vehi-
cles are sealed within the hub and bearing assem-
bly and cannot be inspected or replaced.
Replacement of the hub and bearing is necessary.Tone wheels can cause erratic wheel speed sensor
signals. Inspect tone wheels for the following possible
causes.
²missing, chipped, or broken teeth
²contact with the wheel speed sensor
²wheel speed sensor to tone wheel alignment
²wheel speed sensor to tone wheel clearance
²excessive tone wheel runout
²tone wheel loose on its mounting surface
If a front tone wheel is found to need replacement,
the drive shaft must be replaced. No attempt should
be made to replace just the tone wheel. (Refer to 3 -
DIFFERENTIAL & DRIVELINE/HALF SHAFT -
REMOVAL)
If a rear tone wheel is found to need replacement
on an all-wheel-drive model, the drive shaft must be
replaced. No attempt should be made to replace just
the tone wheel. (Refer to 3 - DIFFERENTIAL &
DRIVELINE/HALF SHAFT - REMOVAL)
If wheel speed sensor to tone wheel contact is evi-
dent, determine the cause and correct it before
replacing the wheel speed sensor or tone wheel.
Check the gap between the speed sensor head and
the tone wheel to ensure it is within specifications.
(Refer to 5 - BRAKES - ABS/ELECTRICAL - SPEC-
IFICATIONS)
Excessive wheel speed sensor runout can cause
erratic wheel speed sensor signals. Refer to SPECI-
FICATIONS in this section of the service manual for
the maximum allowed tone wheel runout (Refer to 5 -
BRAKES - ABS/ELECTRICAL - SPECIFICATIONS).
If tone wheel runout is excessive, determine if it is
caused by a defect in the driveshaft assembly or hub
and bearing. Replace as necessary.
Tone wheels are pressed onto their mounting sur-
faces and should not rotate independently from the
mounting surface. Replacement of the front drive-
shaft, rear driveshaft (AWD only) or rear hub and
bearing is necessary.
TRACTION CONTROL SWITCH
DIAGNOSIS AND TESTING - TRACTION
CONTROL SWITCH
(1) Remove lower column shroud.
(2) Disconnect traction control switch harness from
column harness below column.
(3) Using an ohmmeter, check for continuity read-
ing between pins. Refer to TRACTION CONTROL
SWITCH CONTINUITY test table and (Fig. 5).
Fig. 4 SENSOR CONNECTION AT HUB AND
BEARING
1 - SECONDARY SENSOR RETAINING CLIP
2 - METAL SENSOR RETAINING CLIP
3 - HUB AND BEARING
5 - 92 BRAKES - ABSRS
REAR WHEEL SPEED SENSOR - FWD (Continued)
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HCU (HYDRAULIC CONTROL
UNIT)
DESCRIPTION
The hydraulic control unit (HCU) is mounted to
the CAB as part of the ICU (Fig. 22). The HCU con-
trols the flow of brake fluid to the brakes using a
series of valves and accumulators. A pump/motor is
mounted on the HCU to supply build pressure to the
brakes during an ABS stop.
The HCU on a vehicle equipped with ABS and
traction control has a valve block housing that is
approximately 1 inch longer on the low pressure fluid
accumulators side than a HCU on a vehicle that is
equipped with only ABS.
For more information, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ICU (INTEGRATED CON-
TROL UNIT) - DESCRIPTION)
OPERATION
For information on the operation of the HCU as a
whole, refer to Hydraulic Circuits And Valve Opera-
tion which can be found elsewhere in this section.
For information on the operation of the components
within the HCU, refer to the following three topics.
VALVES AND SOLENOIDS
The valve block contains four inlet valves and four
outlet valves. The inlet valves are spring-loaded in
the open position and the outlet valves are spring-
loaded in the closed position during normal braking.
The fluid is allowed to flow from the master cylinder
to the wheel brakes.
During an ABS stop, these valves cycle to maintain
the proper slip ratio for each wheel. The inlet valve
closes preventing further pressure increase and the
outlet valve opens to provide a path from the wheel
brake to the HCU accumulators and pump/motor.
This releases (decays) pressure from the wheel brake,
thus releasing the wheel from excessive slippage.
Once the wheel is no longer slipping, the outlet valve
is closed and the inlet valve is opened to reapply
(build) pressure.
On vehicles with traction control, there is an extra
set of valves and solenoids. The ASR valves, mounted
in the HCU valve block, are normally in the open
position and close only when the traction control is
applied.
These isolator valves are used to isolate the rear
(non-driving) wheels of the vehicle from the hydraulicpressure that the HCU pump/motor is sending to the
front (driving) wheels when traction control is being
applied. The rear brakes need to be isolated from the
master cylinder when traction control is being
applied so the rear wheels do not drag. For more
information, refer to Traction Control System in this
section.
BRAKE FLUID ACCUMULATORS
There are two fluid accumulators in the HCU±one
for the primary hydraulic circuit and one for the sec-
ondary hydraulic circuit. Each hydraulic circuit uses
a 5 cc accumulator.
The fluid accumulators temporarily store brake
fluid that is removed from the wheel brakes during
an ABS cycle. This stored fluid is used by the pump/
motor to provide build pressure for the brake hydrau-
lic system. When the antilock stop is complete, the
accumulators are drained by the pump/motor.
On ABS-only vehicles, there is a mini-accumulator
on the secondary hydraulic circuit that protects the
master cylinder seals during an ABS stop, and there
is a noise dampening chamber on the primary circuit.
On ABS with traction control vehicles, there are
two noise dampening chambers in the HCU.
PUMP/MOTOR
There are two pump assemblies in the HCUÐone
for the primary hydraulic circuit and one for the sec-
ondary hydraulic circuit. Both pumps are driven by a
common electric motor. This DC-type motor is inte-
gral to the HCU and is controlled by the CAB.
The pump/motor provides the extra amount of
brake fluid needed during antilock braking. Brake
fluid is released to the accumulators when the outlet
valve is opened during an antilock stop. The pump
mechanism consists of two opposing pistons operated
by an eccentric camshaft. In operation, one piston
draws fluid from the accumulators, and the opposing
piston pumps fluid to the master cylinder circuits.
When the antilock stop is complete, the pump/motor
drains the accumulators.
The CAB may turn on the pump/motor when an
antilock stop is detected. The pump/motor continues
to run during the antilock stop and is turned off after
the stop is complete. Under some conditions, the
pump/motor runs to drain the accumulators during
the next drive-off.
The pump/motor is not a serviceable item; if it
requires replacement, the HCU must be replaced.
RSBRAKES - ABS5-99
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(7) Using a brake pedal depressor, move and lock
the brake pedal to a position past the first inch of
pedal travel.This will prevent brake fluid from
draining out of the master cylinder once the
brake tubes are removed from the HCU.
CAUTION: Do not apply a 12±volt power source to
any terminals of the 24-way CAB connector when
disconnected.
(8) Disconnect the wiring harness connector from
the speed control servo.
(9) Remove the speed control servo mounting nuts
and move the servo out of the way.
(10) Disconnect the 24±way connector from the
CAB. To disconnect the 24±way connector, grasp the
lock on the 24±way connector and pull it as far up as
possible. This will unlock the 24±way connector from
the socket on the CAB.
CAUTION: Before removing the brake tubes from
the HCU, the HCU must be thoroughly cleaned. This
must be done to prevent dirt particles from falling
into the ports of HCU or entering the brake tubes.
(11) Thoroughly clean all surfaces of the ICU and
brake tube nuts. Use only a solvent such as Mopart
Brake Parts Cleaner or equivalent to clean the ICU.
(12) Remove the brake tubes (4) from the outlet
ports on the HCU (Fig. 14).
(13) Remove the primary and secondary brake
tubes from the inlet ports on the HCU (Fig. 14).
(14) Center and prop the steering wheel.
(15) Remove the silencer panel under the instru-
ment panel, below the steering column.(16) Remove the pinch bolt and disconnect the
steering shaft coupling.
(17) Remove the two clips securing silencer to dash
seal (Fig. 15).
(18) Remove the three screws securing the dash
seal (Fig. 15).
(19) Remove the 3 bolts attaching the ICU to its
mounting bracket (Fig. 16).
(20) Remove ICU from the vehicle through engine
compartment.
(21) If required, to separating the CAB from the
HCU, (Refer to 5 - BRAKES - ABS/HYDRAULIC/ME-
CHANICAL/ICU (INTEGRATED CONTROL UNIT) -
DISASSEMBLY).
REMOVAL - RHD
NOTE: Before proceeding, (Refer to 5 - BRAKES -
WARNING)(Refer to 5 - BRAKES - CAUTION)
(1) Disconnect the negative (ground) cable from
the battery and isolate cable.
(2) Using a brake pedal depressor, move and lock
the brake pedal to a position past the first inch of
pedal travel.This will prevent brake fluid from
Fig. 14 BRAKE TUBE NUTS AT ICU
1 - PRIMARY BRAKE TUBE
2 - SECONDARY BRAKE TUBE
3 - CHASSIS BRAKE TUBES
Fig. 15 LOWER COUPLING AND DASH SEAL
1 - COUPLING
2 - DASH SEAL
3 - SILENCER
4 - MOUNTING SCREWS
5 - RETAINING CLIPS
6 - DASH
RSBRAKES - ABS5 - 101
ICU (INTEGRATED CONTROL UNIT) (Continued)
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INSTALLATION
INSTALLATION - LHD
(1) Place the ICU in its bracket below the master
cylinder. Start the upper mounting bolt to hold it in
place.
(2) Inside the vehicle, install the remaining 2
mounting bolts attaching the ICU to the mounting
bracket (Fig. 16). Tighten all 3 mounting bolts to a
torque of 11 N´m (97 in. lbs.).
(3) Install the dash seal and three mounting
screws (Fig. 15).(4) Install the silencer on top of the dash seal (Fig.
15).
(5) Connect the steering shaft coupling and install
the pinch bolt (Fig. 15). Tighten the pinch bolt to 28
N´m (250 in. lbs.).
(6) Install the silencer panel below the steering
column under the instrument panel.
(7) Remove the steering wheel holder.
CAUTION: Because of the flexible section in the pri-
mary and secondary brake tubes, the brake tubes
must be held in proper orientation when tightened
and torqued. These tubes must not contact each
other or other vehicle components when installed.
Also, after the brake tubes are installed on the HCU,
ensure all spacer clips are reinstalled on the brake
tubes.
(8) Install the primary and secondary brake tubes
into their correct port locations on the HCU valve
block (Fig. 14). Tighten the tube nuts to a torque of
17 N´m (145 in. lbs.).
CAUTION: When installing the chassis brake tubes
on the HCU valve block, they must be located cor-
rectly in the valve block to ensure proper ABS oper-
ation.
NOTE: The chassis brake tube attachment locations
to the HCU, are marked on the bottom of the CAB.
(9) Install the (4) chassis brake tubes into their
correct port locations on the HCU valve block as
shown (Fig. 14). Tighten the tube nuts to a torque of
17 N´m (145 in. lbs.).
Fig. 22 INTEGRATED CONTROL UNIT (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
Fig. 23 (TYPICAL) CAB Attaching Bolts
1 - MOUNTING BOLTS
2 - CAB
3 - HCU VALVE BLOCK
Fig. 24 (TYPICAL) Remove/Install CAB
1 - CAB
2 - HCU VALVES
3 - HCU VALVE BLOCK
5 - 104 BRAKES - ABSRS
ICU (INTEGRATED CONTROL UNIT) (Continued)
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RELEASE SYSTEM
All models utilize a hydraulic clutch release sys-
tem, conisting of a clutch master cylinder attached to
the clutch pedal (Fig. 3), and a slave cylinder fas-
tened to the transaxle which operates the clutch
release lever (Fig. 4). When the driver depresses the
clutch pedal, the master cylinder pushrod travels
through the cylinder bore, displacing fluid through
the master cylinder plumbing. This fluid displace-
ment forces the slave cylinder piston to travel, forc-
ing the clutch release bearing into the clutch
diaphragm spring via the release lever and leverage
(Fig. 5). This releases the clamping force on the
clutch disc, allowing the engine crankshaft to rotate
independently from the transaxle input shaft.
Fig. 2 Clutch Disc and Pressure PlateÐ2.5L TD Engines
1 - FLYWHEEL
2 - DISC3 - PRESSURE PLATE
Fig. 3 Clutch Master CylinderÐTypical
6 - 2 CLUTCHRS
CLUTCH (Continued)
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DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CLUTCH SYSTEM
Clutch problem diagnosis will generally require a
road test to determine the type of fault. Componentinspection will then determine the problem after road
testing.
Drive the vehicle at normal speeds during road
test. Shift the transaxle through all gear ranges and
observe clutch action. If chatter, grab, slip, or
improper release is experienced, remove and inspect
the clutch components. If the problem is noise or
hard shifting, further diagnosis may be needed. The
transaxle or other driveline components may actually
be at fault.
SERVICE DIAGNOSIS - CLUTCH GRAB/CHATTER
CONDITION POSSIBLE CAUSES CORRECTION
CLUTCH DISC FACING
COVERED WITH OIL OR
GREASEOil leak at engine rear main or
transaxle input shaft seal.Correct leak and replace modular clutch
assembly (2.4L Gas) or clutch cover and
disc (2.5L TD).
Too much grease applied to splines
of disc and input shaft.Apply lighter coating of grease to splines.
NO FAULT FOUND WITH
CLUTCH
COMPONENTSProblem actually related to
suspension or driveline component.Further diagnosis required. Check
engine/transmission mounts, suspension
attaching parts and other driveline
components as needed.
Engine related problems. Check EFI and ignition systems.
PARTIAL ENGAGEMENT
OF CLUTCH DISCClutch cover, spring, or release
fingers bent, distorted (rough
handling, improper assembly).Replace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
Fig. 4 Slave Cylinder Removal/Installation
1 - MOUNTING HOLE
2 - SLAVE CYLINDER
3 - ACCESS HOLE
4 - NYLON ANTI-ROTATION TAB
Fig. 5 Release Bearing and Lever
1 - RELEASE LEVER
2 - RELEASE BEARING
RSCLUTCH6-3
CLUTCH (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
Clutch disc damaged or distorted. Replace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
Clutch misalignment. Verify modular clutch pilot plate alignment
to crankshaft. Replace the modular clutch
assembly (2.4L Gas) or clutch cover and
disc (2.5L TD) if the pilot plate is loose or
bent.
Improper transaxle-to-engine
installation.Verify transaxle is properly installed to
engine.
SERVICE DIAGNOSIS - CLUTCH SLIPS
CONDITION POSSIBLE CAUSES CORRECTION
DISC FACING WORN OUT Normal wear. Replace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
Driver frequently rides (slips) clutch,
results in rapid wear, overheating.Replace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
Insufficient clutch cover diaphragm
spring tensionReplace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
CLUTCH DISC FACING
CONTAMINATED WITH
OIL OR GREASELeak at rear main oil seal or
transaxle input shaft sealReplace leaking seals. Replace modular
clutch assembly (2.4L Gas) or clutch cover
and disc (2.5L TD).
Excessive amount of grease applied
to input shaft splinesApply less grease to input shaft. Replace
modular clutch assembly (2.4L Gas) or
clutch cover and disc (2.5L TD).
Road splash, water entering housing Seal housing. Inspect clutch assembly.
CLUTCH IS RUNNING
PARTIALLY DISENGAGEDRelease bearing sticking or binding,
does not return to normal running
position.Verify that bearing is actually binding. Then,
replace bearing and transmission front
bearing retainer if sleeve surface is
damaged.
Clutch pedal not returning to static
position.Inspect pedal assembly for damage and/or
obstructions. Replace componnents as
necessary.
Clutch master cylinder or pushrod
damaged causing high preload.Replace clutch master cylinder assembly.
Slave cylinder binding or stuck. Replace slave cylinder.
CLUTCH DISC FACINGS
HAVE FRACTURED INTO
SMALL PIECESLeak at rear main or transaxle input
shaft sealReplace seal. Replace modular clutch
assembly (2.4L Gas) or clutch cover and
disc (2.5L TD)..
Excessive heat from slippage Replace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
6 - 4 CLUTCHRS
CLUTCH (Continued)
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