2002 CHRYSLER CARAVAN service

(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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ICU (INTEGRATED CONTROL
UNIT)
DESCRIPTION
The hydraulic control unit (HCU) and the control-
ler antilock brake (CAB) used with this antilock
brake system are combined (integrated) into one
unit, which is called the integrated control unit (ICU)
(Fig. 12). The ICU is located below the master cylin-
der in the engine compartment (Fig. 13).Two different ICU's (HCU and CAB) are used on
this vehicle depending on whether or not the vehicle
is equipped with traction control. The HCU on a
vehicle equipped with traction control has a valve
block that is approximately one inch longer than a
HCU on a vehicle that is equipped with ABS only.
The ABS-only ICU consists of the following compo-
nents: the CAB, eight (build/decay) solenoid valves
(four inlet valves and four outlet valves), valve block,
fluid accumulators, a pump, and an electric motor.
The ABS-with traction control ICU consists of the
following components: the CAB, eight (build/decay)
solenoid valves (four inlet valves and four outlet
valves), two traction control (ASR) valves, two
hydraulic shuttle valves, valve block, fluid accumula-
tors, a pump, and an electric motor.
The replaceable components of the ICU are the
HCU and the CAB. No attempt should be made to
service any individual components of the HCU or
CAB. For information on the CAB, (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/CONTROLLER ANTILOCK BRAKE -
DESCRIPTION).
OPERATION
For information of the ICU, refer to these individ-
ual components of the ICU:
²CONTROLLER ANTILOCK BRAKE (CAB)
(Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/CONTROLLER ANTILOCK
BRAKE - OPERATION)
²HYDRAULIC CONTROL UNIT (HCU) (Refer to
5 - BRAKES - ABS/HYDRAULIC/MECHANICAL/
HCU (HYDRAULIC CONTROL UNIT) - OPERA-
TION)
For information on the ICU's hydraulic circuits,
refer to HYDRAULIC CIRCUITS AND VALVE
OPERATION. (Refer to 5 - BRAKES - ABS/HY-
DRAULIC/MECHANICAL - OPERATION)
REMOVAL
REMOVAL - LHD
(1) Disconnect the negative (ground) cable from
the battery and isolate cable.
(2) Remove the battery shield.
(3) Remove the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - REMOVAL).
(4) Disconnect the vacuum hose connector at the
tank built into the battery tray.
(5) Remove the screw securing the engine coolant
filler neck to the battery tray.
(6) Remove the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - REMOVAL).
Fig. 12 INTEGRATED CONTROL UNIT (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
Fig. 13 ICU LOCATION IN VEHICLE
1 - POWER BRAKE BOOSTER
2 - MASTER CYLINDER
3 - ICU
5 - 100 BRAKES - ABSRS
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CLUTCH
TABLE OF CONTENTS
page page
CLUTCH
DESCRIPTION..........................1
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CLUTCH
SYSTEM.............................3
DIAGNOSIS AND TESTING - DRIVE PLATE
MISALIGNMENT.......................5
DIAGNOSIS AND TESTING - CLUTCH
COVER AND DISC RUNOUT..............6
DIAGNOSIS AND TESTING - CLUTCH
CHATTER COMPLAINTS.................6
SPECIAL TOOLS - T850 TRANSAXLE........6
CLUTCH RELEASE LEVER AND BEARING
REMOVAL.............................6
INSTALLATION..........................7
MASTER CYLINDER - RHD
REMOVAL.............................8INSTALLATION..........................8
MASTER CYLINDER - LHD
REMOVAL.............................9
INSTALLATION.........................10
MODULAR CLUTCH ASSY - 2.4L GAS
REMOVAL.............................11
INSTALLATION.........................11
SLAVE CYLINDER
REMOVAL.............................11
INSTALLATION.........................11
CLUTCH DISC AND PRESSURE PLATE - 2.5L
TD
REMOVAL.............................12
INSTALLATION.........................12
FLYWHEEL
REMOVAL.............................13
INSTALLATION.........................13
CLUTCH
DESCRIPTION
CLUTCH COMPONENTS
Models equipped with a 2.4L Gas engine utilize a
modular clutch assembly (Fig. 1). The modular clutch
consists of a single, dry-type clutch disc, a diaphragm
style clutch cover, and an integrated flywheel. The
clutch cover (pressure plate) is riveted to the fly-
wheel, and therefore can only be serviced as an
assembly.
Models equipped with the 2.5L Turbo Diesel engine
utilize a conventional clutch system (Fig. 2). This
system consists of a flywheel, clutch disc, and clutch
cover (pressure plate), which is fastened to the fly-
wheel, capturing the clutch disc within. Each compo-
nent is individually serviceable, however it ishighly
recommended that the clutch cover and disc be
replaced as a set.
Fig. 1 Modular Clutch AssemblyÐ2.4L Gas Engines
1 - MODULAR CLUTCH ASSEMBLY
RSCLUTCH6-1
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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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SERVICE DIAGNOSIS - IMPROPER CLUTCH RELEASE
CONDITION POSSIBLE CAUSES CORRECTION
CLUTCH DISC BINDS ON
INPUT SHAFT SPLINESClutch disc hub splines damaged
during installationClean, smooth, and lubricate disc and shaft
splines. Replace modular clutch assembly,
or clutch disc, and/or input shaft if splines
are severely damaged.
Input shaft splines rough, damaged. Clean input shaft splines. Then lube.
Corrosion or rust formations on
splines of input shaft and discClean input shaft splines and disc splines,
then lube
CLUTCH DISC RUSTED
TO FLYWHEEL AND/OR
PRESSURE PLATEOccurs in vehicles stored or not
driven for extended period of time.
Also occurs after steam cleaning if
vehicle is not used for extended
period.Replace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
CLUTCH WILL NOT
DISENGAGE PROPERLYDisc bent, distorted during transaxle
installationReplace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
Clutch cover diaphragm spring
damaged during transaxle installationReplace modular clutch assembly (2.4L
Gas) or clutch cover and disc (2.5L TD).
Release fork bent, loose, or
damagedReplace fork if worn or damaged
Air in clutch hydraulic circuit. Allow system to self-bleed or replace
hydraulic components.
Leak in clutch hydraulic circuit. Replace worn/damaged/leaking hydraulic
components.
Clutch pedal requires
excessive force (high
release load).Clutch disc is worn. Replace modular clutch assembly (2.4L
models) or clutch cover and disc (2.5L TD
models).
SERVICE DIAGNOSIS - CLUTCH PEDAL NOISE
CONDITION POSSIBLE CAUSES CORRECTION
CLUTCH PEDAL
SQUEAKS WHEN
DEPRESSED TO FLOORPedal bushings worn out or
inadequate lubricationReplace or lubricate bushings at clutch
pedal pivot or master cylinder pushrod.
Clutch pedal return spring worn out Lubricate or replace return spring
CLUTCH PEDAL
SQUEAKS DURING
OPERATIONClutch release lever pivot stud has
inadequate lubricationLubricate or replace clutch release lever
DIAGNOSIS AND TESTING - DRIVE PLATE
MISALIGNMENT
Common causes of misalignment are:
²Heat warping
²Mounting drive plate on a dirty crankshaft
flange
²Incorrect bolt tightening
²Improper seating on the crankshaft shoulder²Loose crankshaft bolts
Clean the crankshaft flange before mounting the
drive plate. Dirt and grease on the flange surface
may misalign the flywheel, causing excessive runout.
Use new bolts when mounting drive plate to crank-
shaft. Tighten drive plate bolts to specified torque
only. Over-tightening can distort the drive plate hub
causing excessive runout.
RSCLUTCH6-5
CLUTCH (Continued)
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STANDARD PROCEDURE - COOLANT LEVEL
CHECK
NOTE: Do not remove radiator cap for routine cool-
ant level inspections.
The coolant reserve system provides a quick visual
method for determining the coolant level without
removing the radiator cap.With the engine cold
and not running,simply observe the level of the
coolant in the recovery/reserve container (Fig. 7). The
coolant level should be between the MIN and MAX
marks.
Fig. 6 Cooling System Service Locations
1 - COOLANT RECOVERY CONTAINER 3 - ENGINE OIL LEVEL DIPSTICK
2 - ENGINE OIL FILL CAP 4 - RADIATOR PRESSURE CAP
Fig. 7 Coolant Recovery Container
RSCOOLING7-5
COOLING (Continued)
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