2003 CHRYSLER CARAVAN automatic transmission

REAR DRIVELINE MODULE
TABLE OF CONTENTS
page page
REAR DRIVELINE MODULE
DESCRIPTION.........................23
OPERATION...........................23
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REAR
DRIVELINE MODULE NOISE.............24
DIAGNOSIS AND TESTING - REAR
DRIVELINE MODULE OPERATION........26
REMOVAL.............................26
DISASSEMBLY.........................27
ASSEMBLY............................29
INSTALLATION.........................33
SPECIFICATIONS - REAR DRIVELINE
MODULE............................34
SPECIAL TOOLS.......................34
BI-DIRECTIONAL OVERRUNNING CLUTCH
DESCRIPTION.........................34
OPERATION...........................36
DIFFERENTIAL ASSEMBLY
DESCRIPTION.........................39OPERATION...........................39
FLUID - DIFFERENTIAL ASSEMBLY
STANDARD PROCEDURE - DIFFERENTIAL
ASSEMBLY FLUID CHANGE.............40
FLUID - OVERRUNNING CLUTCH HOUSING
STANDARD PROCEDURE - OVERRUNNING
CLUTCH HOUSING FLUID CHANGE.......41
VISCOUS COUPLER
DESCRIPTION.........................41
OPERATION...........................42
TORQUE ARM
REMOVAL.............................44
INSTALLATION.........................44
INPUT FLANGE SEAL
REMOVAL.............................44
INSTALLATION.........................45
OUTPUT FLANGE SEAL
REMOVAL.............................45
INSTALLATION.........................46
REAR DRIVELINE MODULE
DESCRIPTION
The rear driveline module assembly (Fig. 1) con-
sists of four main components:
²Bi-Directional Overrunning Clutch (BOC)
²Viscous Coupling
²Differential Assembly
²Torque Arm
The viscous coupling and bi-directional overrun-
ning clutch are contained within an overrunning
clutch housing, which fastens to the differential
assembly. The overrunning clutch housing and differ-
ential assembly have unique fluid sumps, each
requiring their own type and capacity of fluid. The
overrunning clutch housing requires MopartATF+4
(Automatic Transmission FluidÐType 9602) or equiv-
alent. The differential assembly requires Mopart
80W-90 Gear and Axle Lubricant.
Driveline module service is limited to the following
components:
²Differential Assembly (serviced only as assem-
bly)
²Viscous Coupling
²Bi-Directional Overrunning Clutch (BOC)
²Overrunning Clutch Housing²Seals (Input Flange, Output Flange, Overrun-
ning Clutch Housing O-rings)
²Input Flange/Shield
²Torque Arm
²Vents
²Fasteners
OPERATION
The primary benefits of All Wheel Drive are:
²Superior straight line acceleration, and corner-
ing on all surfaces
²Better traction and handling under adverse con-
ditions, resulting in improved hill climbing ability
and safer driving.
The heart of the system is an inter-axle viscous
coupling. The vehicle retains predominantly front-
wheel drive characteristics, but the All Wheel Drive
capability takes effect when the front wheels start to
slip. Under normal level road, straight line driving,
100% of the torque is allocated to the front wheels.
The viscous coupling controls and distributes torque/
power to the rear wheels. The viscous coupling trans-
mits torque to the rear wheels in proportion of the
amount of the slippage at the front wheels. Thais
variable torque distribution is automatic with no
driver inputs required. The coupling is similar to a
multi-plate clutch. It consists of a series of closely
spaced discs, which are alternately connected to the
RSREAR DRIVELINE MODULE3-23
ProCarManuals.com

front and rear drive units. The unit is totally sealed
and partially filled with silicone fluid. There is no
adjustment, maintenance or fluid checks required
during the life of the unit.
The overrunning clutch allows the rear wheels to
overrun the front wheels during a rapid front wheel
lock braking maneuver. The overrunning action pre-
vents any feed-back of front wheel braking torque to
the rear wheels. It also allows the braking system to
control the braking behavior as a two wheel drive
(2WD) vehicle.
The overrunning clutch housing has a separate oil
sump and is filled independently from the differen-
tial. The fill plug is located on the side of the over-
running clutch case. When filling the overrunning
clutch with lubricant use MopartATF+4 (Automatic
Transmission FluidÐType 9602) or equivalent.
The differential assembly contains a conventional
open differential with hypoid ring gear and pinion
gear set. The hypoid gears are lubricated by SAE
80W-90 gear lubricant.DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REAR DRIVELINE
MODULE NOISE
Different sources can be the cause of noise that the
rear driveline module assembly is suspected of mak-
ing. Refer to the following causes for noise diagnosis.
DRIVELINE MODULE ASSEMBLY NOISE
The most important part of driveline module ser-
vice is properly identifying the cause of failures and
noise complaints. The cause of most driveline module
failures is relatively easy to identify. The cause of
driveline module noise is more difficult to identify.
If vehicle noise becomes intolerable, an effort
should be made to isolate the noise. Many noises that
are reported as coming from the driveline module
may actually originate at other sources. For example:
²Tires
²Road surfaces
²Wheel bearings
Fig. 1 AWD Driveline Module Assembly
1 - TORQUE ARM 8 - WASHER 15 - PLUG-OVERRUNNING CLUTCH
HOUSING DRAIN
2 - INPUT FLANGE 9 - BI-DIRECTIONAL OVERRUNNING
CLUTCH (BOC)16 - SNAP RING
3 - FLANGE NUT 10 - VISCOUS COUPLER 17 - BEARING
4 - WASHER 11 - SHIM (SELECT) 18 - OVERRUNING CLUTCH HOUSING
5 - SHIELD 12 - O-RING 19 - SEAL-INPUT FLANGE
6 - VENT 13 - DIFFERENTIAL ASSEMBLY
7 - O-RING 14 - PLUG-DIFFERENTIAL FILL
3 - 24 REAR DRIVELINE MODULERS
REAR DRIVELINE MODULE (Continued)
ProCarManuals.com

(5) Re-position the drain pan under the differential
fill plug.
(6) Remove the differential fill plug (Fig. 41).
(7) Using a suction gun (Fig. 42) or equivalent, fill
the differential assembly with 0.7 L (1.48 pts.) of
MopartGear and Axle Lubricant (80W-90).
(8) Install the fill plug and torque to 35 N´m (26 ft.
lbs.).
FLUID - OVERRUNNING
CLUTCH HOUSING
STANDARD PROCEDURE - OVERRUNNING
CLUTCH HOUSING FLUID CHANGE
(1) Raise vehicle on hoist.
(2) Position a drain pan under overrunning clutch
housing drain plug.
(3) Remove overrunning clutch housing drain plug
and drain fluid (Fig. 43).
(4) Install the drain plug and torque to 30 N´m (22
ft. lbs.).
(5) Re-position the drain pan under the overrun-
ning clutch housing fill plug.
(6) Remove fill plug (Fig. 44).
(7) Using a suction gun (Fig. 45), add 0.58 L (1.22
pts.) of MopartATF+4 (Automatic Transmission Flu-
idÐType 9602).
(8) Install fill plug and torque to 30 N´m (22 ft.
lbs.).
VISCOUS COUPLER
DESCRIPTION
The heart of the all-wheel drive system is the
inter-axle viscous coupling and bi-directional over-
running clutch. Under normal driving the vehicle
retains predominantly front wheel drive characteris-
tics. The all-wheel drive takes effect when the front
wheels start to slip. Under normal level road,
straight line driving, 100% of the torque is allocated
to the front wheels. The viscous coupler allows more
Fig. 42 Filling Differential
1 - DIFFERENTIAL ASSEMBLY
2 - SUCTION GUN
Fig. 43 Overrunning Clutch Case Drain Plug
1 - OVERRUNNING CLUTCH HOUSING DRAIN PLUG
Fig. 44 Overrunning Clutch Housing Fill Plug
1 - OVERRUNNING CLUTCH HOUSING FILL PLUG
2 - FUEL TANK
RSREAR DRIVELINE MODULE3-41
FLUID - DIFFERENTIAL ASSEMBLY (Continued)
ProCarManuals.com

OPERATION
OPERATION - COOLING SYSTEM
The engine cooling systems primary purpose is to
maintain engine temperature in a range that will
provide satisfactory engine performance and emission
levels under all expected driving conditions. It also
provides hot water (coolant) for heater performance
and cooling for automatic transmission oil. It does
this by transferring heat from engine metal to cool-
ant, moving this heated coolant to the radiator, and
then transferring this heat to the ambient air.
²When engine is cold: thermostat is closed, cool-
ing system has no flow through the radiator. The
coolant bypass flows through the engine only.
²When engine is warm: thermostat is open, cool-
ing system has bypass flow and coolant flow through
radiator.
Coolant flow circuits for the 2.4L and 3.3/3.8L
engines are shown in (Fig. 2).
OPERATION - HOSE CLAMPS
The spring type hose clamp applies constant ten-
sion on a hose connection. To remove a spring type
hose clamp, use Special Tool 6094 or equivalent, con-
stant tension clamp pliers (Fig. 3) to compress the
hose clamp.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - COOLING SYSTEM
LEAK TEST
WARNING: THE WARNING WORDS ªDO NOT OPEN
HOTº ON THE RADIATOR PRESSURE CAP IS A
SAFETY PRECAUTION. WHEN HOT, PRESSURE
BUILDS UP IN COOLING SYSTEM. TO PREVENT
SCALDING OR INJURY, THE RADIATOR CAP
SHOULD NOT BE REMOVED WHILE THE SYSTEM
IS HOT OR UNDER PRESSURE.
Fig. 2 Cooling System Flow
1 - HEATER - REAR (3.3/3.8L OPTIONAL EQUIPMENT) 6 - WATER PUMP
2 - HEATER - FRONT 7 - RADIATOR
3 - ENGINE 8 - COOLANT RECOVERY/RESERVE CONTAINER
4 - THERMOSTAT 9 - COOLANT FLOW - PRESSURE CAP VACUUM
5 - ENGINE OIL COOLER (3.3/3.8L OPTIONAL EQUIPMENT) 10 - COOLANT FLOW - PRESSURE CAP RELIEF
7 - 2 COOLINGRS
COOLING (Continued)
ProCarManuals.com

(5) Obtain ignition keys to be programmed from
customer (8 keys maximum).
(6) Using the DRB III, erase all ignition keys by
selecting MISCELLANEOUS and ERASE ALL CUR-
RENT IGN. KEYS.
(7) Program all ignition keys.
Learned Key In Ignition - Ignition key transponder
ID is currently programmed in SKIM memory.
BODY CONTROL MODULE
DESCRIPTION
The Body Control Module (BCM) is located in the
passenger compartment, attached to the bulkhead
underneath the left side of the instrument panel.
The BCM utilizes integrated circuitry and informa-
tion carried on the Programmable Communications
Interface (PCI) data bus network along with many
hard wired inputs to monitor many sensor and
switch inputs throughout the vehicle. In response to
those inputs, the internal circuitry and programming
of the BCM allow it to control and integrate many
electronic functions and features of the vehicle
through both hard wired outputs and the transmis-
sion of electronic message outputs to other electronic
modules in the vehicle over the PCI data bus.
OPERATION
The Body Control Module (BCM) supplies vehicle
occupants with visual and audible information and
controls various vehicle functions. To provide and
receive information, the BCM is interfaced to the
vehicle's serial bus communications network, referred
to as the Programmable Communications Interface
(PCI) bus.
This network consists of the;
²Powertrain Control Module (PCM)
²Transmission Control Module (TCM)
²Mechanical Instrument Cluster (MIC)
²Occupant Restraint Controller (ORC)
²Compass/Mini-Trip Computer (CMTC)
²Electronic Vehicle Information Center (EVIC)
²Controller Antilock Brake (CAB)²HVAC Control Module
²Sliding Door Control Modules (driver and pas-
senger side doors)
²Power Liftgate Module (PLG)
²Audio system equipped with RAZ, RBU, RBK,
and RBB radios.
²Side Impact Airbag Control Module (SIACM)
²Memory Seat Module (MSM)
²Sentry Key Immobilizer Module (SKIM)
The BCM is operational when battery power is
supplied to the module.
The BCM provides the following features:
²Power Door Locks
²Automatic Door Locks
²Battery Protection - The BCM will automatically
turn off all exterior lamps after 3 minutes, and all
interior lamps after 15 minutes after the ignition is
turned off, if they are not turned off by the driver.
²Chime Control
²Compass/Mini-Trip support.
²Interior Lighting (Courtesy/Reading Lamps)
²BCM Diagnostic Reporting
²Electronic Liftgate Release (with Power Door
Locks)
²Exterior Lighting
²Headlamp Time Delay (with/without Automatic
Headlamps)
²Illuminated Entry
²Fade to Off Interior Lamps - This feature dims
the interior lighting (courtesy lamps) gradually if the
BCM does not receive any new inputs that would
cause the interior lamps to remain on.
²Pulse Width Modulated Instrument Panel Dim-
ming
²Door Lock Inhibit - This feature disables the
door lock functions if the key is in the ignition and
either front door is ajar. Pressing the Remote Keyless
Entry (RKE) lock/unlock button under these condi-
tions result in normal lock/unlock activation.
The BCM has the ability to LEARN additional fea-
tures in the vehicle, provided the appropriate switch
input and PCI data bus messages are received. Refer
to the LEARNED FEATURES table.
RSELECTRONIC CONTROL MODULES8E-3
ELECTRONIC CONTROL MODULES (Continued)
ProCarManuals.com

NOTE: PCM Inputs:
²Air Conditioning Pressure Transducer
²Ambient temperature Sensor
²ASD Relay
²Battery Temperature Sensor (NGC)
²Battery Voltage
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Distance Sensor (from transmission control mod-
ule)
²EGR Position Feedback
²Engine Coolant Temperature Sensor
²Heated Oxygen Sensors
²Ignition sense
²Intake Air Temperature Sensor
²Knock Sensor
²Leak Detection Pump Feedback
²Manifold Absolute Pressure (MAP) Sensor
²Park/Neutral
²PCI Bus
²Power Steering Pressure Switch
²Proportional Purge Sense
²SCI Receive
²Speed Control
²Throttle Position Sensor
²Torque Management Input
²Transaxle Control Module (3.3/3.8L Only)
²Transmission Control Relay (Switched B+) (2.4L
Only)
²Transmission Pressure Switches (2.4L Only)
²Transmission Temperature Sensor (2.4L Only)
²Transmission Input Shaft Speed Sensor (2.4L
Only)
²Transmission Output Shaft Speed Sensor (2.4L
Only)
²Transaxle Gear Engagement
²Vehicle Speed
NOTE: PCM Outputs:
²Air Conditioning Clutch Relay
²Automatic Shut Down (ASD) and Fuel Pump
Relays
²Data Link Connector (PCI and SCI Transmit)
²Double Start Override
²EGR Solenoid
²Fuel Injectors
²Generator Field
²High Speed Fan Relay
²Idle Air Control Motor
²Ignition Coils
²Leak Detection Pump
²Low Speed Fan Relay
²MTV Actuator
²Proportional Purge Solenoid²SRV Valve
²Speed Control Relay
²Speed Control Vent Relay
²Speed Control Vacuum Relay
²8 Volt Output
²5 Volt Output
²Torque Reduction Request
²Transmission Control Relay (2.4L Only)
²Transmission Solenoids (2.4L Only)
²Vehicle Speed
Based on inputs it receives, the powertrain control
module (PCM) adjusts fuel injector pulse width, idle
speed, ignition timing, and canister purge operation.
The PCM regulates the cooling fans, air conditioning
and speed control systems. The PCM changes gener-
ator charge rate by adjusting the generator field.
The PCM adjusts injector pulse width (air-fuel
ratio) based on the following inputs.
²Battery Voltage
²Intake Air Temperature Sensor
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Exhaust Gas Oxygen Content (heated oxygen
sensors)
²Manifold Absolute Pressure
²Throttle Position
The PCM adjusts engine idle speed through the
idle air control motor based on the following inputs.
²Brake Switch
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Park/Neutral
²Transaxle Gear Engagement
²Throttle Position
²Vehicle Speed
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Intake Air Temperature
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Knock Sensor
²Manifold Absolute Pressure
²Park/Neutral
²Transaxle Gear Engagement
²Throttle Position
The automatic shut down (ASD) and fuel pump
relays are mounted externally, but turned on and off
by the powertrain control module through the same
circuit.
The camshaft and crankshaft signals are sent to
the powertrain control module. If the PCM does not
receive both signals within approximately one second
of engine cranking, it deactivates the ASD and fuel
pump relays. When these relays are deactivated,
power is shut off to the fuel injectors, ignition coils,
8E - 12 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)
ProCarManuals.com

B(+) terminal stud. If you probe the battery positive
terminal post and the battery positive cable eyelet
terminal at the starter solenoid B(+) terminal stud,
you are reading the combined voltage drop in the
battery positive cable terminal clamp-to-terminal
post connection and the battery positive cable.
VOLTAGE DROP TEST
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing this
test, be certain that the following procedures are
accomplished:
²The battery is fully-charged and load tested.
Refer to Standard Procedures for the proper battery
charging and load test procedures.
²Fully engage the parking brake.
²If the vehicle is equipped with an automatic
transmission, place the gearshift selector lever in the
Park position. If the vehicle is equipped with a man-
ual transmission, place the gearshift selector lever in
the Neutral position and block the clutch pedal in the
fully depressed position.
²Verify that all lamps and accessories are turned
off.
²To prevent the engine from starting, remove the
Automatic Shut Down (ASD) relay. The ASD relay is
located in the Intelligent Power Module (IPM), in the
engine compartment. See the fuse and relay layout
label affixed to the underside of the IPM cover for
ASD relay identification and location.
(1) Connect the positive lead of the voltmeter to
the battery negative terminal post. Connect the neg-
ative lead of the voltmeter to the battery negative
cable terminal clamp (Fig. 13). Rotate and hold the
ignition switch in the Start position. Observe the
voltmeter. If voltage is detected, correct the poor con-
nection between the battery negative cable terminal
clamp and the battery negative terminal post.
(2) Connect the positive lead of the voltmeter to
the battery positive terminal post. Connect the nega-
tive lead of the voltmeter to the battery positive cable
terminal clamp (Fig. 14). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. If
voltage is detected, correct the poor connection
between the battery positive cable terminal clamp
and the battery positive terminal post.
(3) Connect the voltmeter to measure between the
battery positive cable terminal clamp and the starter
solenoid B(+) terminal stud (Fig. 15). Rotate and hold
the ignition switch in the Start position. Observe the
voltmeter. If the reading is above 0.2 volt, clean and
tighten the battery positive cable eyelet terminal con-
nection at the starter solenoid B(+) terminal stud.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery positive cable.(4) Connect the voltmeter to measure between the
battery negative cable terminal clamp and a good
clean ground on the engine block (Fig. 16). Rotate
and hold the ignition switch in the Start position.
Observe the voltmeter. If the reading is above 0.2
volt, clean and tighten the battery negative cable
eyelet terminal connection to the engine block.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery negative cable.
Fig. 13 Testing Battery Negative Connection
Resistance
1 - VOLTMETER
2 - BATTERY
Fig. 14 Testing Battery Positive Connection
Resistance
1 - VOLTMETER
2 - BATTERY
RSBATTERY SYSTEM8F-17
BATTERY CABLES (Continued)
ProCarManuals.com

CONDITION POSSIBLE CAUSE CORRECTION
2. STARTING CIRCUIT
WIRING FAULTY.2. REFER TO THE FEED CIRCUIT RESISTANCE TEST AND
THE FEED CIRCUIT TEST IN THIS SECTION. REPAIR AS
NECESSARY.
3. STARTER ASSEMBLY
FAULTY.3. IF ALL OTHER STARTING SYSTEM COMPONENTS AND
CIRCUITS CHECK OK, REPLACE STARTER ASSEMBLY.
4. ENGINE SEIZED. 4. REFER TO THE ENGINE SECTION, FOR DIAGNOSTIC AND
SERVICE PROCEDURES.
5. LOOSE
CONNECTION AT
BATTERY, PDC,
STARTER, OR ENGINE
GROUND.5. INSPECT FOR LOOSE CONNECTIONS.
6. FAULTY TEETH ON
RING GEAR.6. ROTATE FLYWHEEL 360É, AND INSPECT TEETH AND RING
GEAR REPLACED IF DAMAGED.
STARTER
ENGAGES,
SPINS OUT
BEFORE
ENGINE
STARTS.1. BROKEN TEETH ON
STARTER RING GEAR.1. REMOVE STARTER. INSPECT RING GEAR AND REPLACE
IF NECESSARY.
2. STARTER ASSEMBLY
FAULTY.2. IF ALL OTHER STARTING SYSTEM COMPONENTS AND
CIRCUITS CHECK OK, REPLACE STARTER ASSEMBLY.
STARTER DOES
NOT
DISENGAGE.1. STARTER
IMPROPERLY
INSTALLED.1. INSTALL STARTER. TIGHTEN STARTER MOUNTING
HARDWARE TO CORRECT TORQUE SPECIFICATIONS.
2. STARTER RELAY
FAULTY.2. REFER TO RELAY TEST, IN THIS SECTION. REPLACE
RELAY, IF NECESSARY.
3. IGNITION SWITCH
FAULTY.3. REFER TO IGNITION SWITCH TEST, IN THE STEERING
SECTION. REPLACE SWITCH, IF NECESSARY.
4. STARTER ASSEMBLY
FAULTY.4. IF ALL OTHER STARTING SYSTEM COMPONENTS AND
CIRCUITS CHECK OK, REPLACE STARTER ASSEMBLY.
5. FAULTY TEETH ON
RING GEAR.5. ROTATE FLYWHEEL 360É, AND INSPECT TEETH AND RING
GEAR REPLACED IF DAMAGED.
DIAGNOSIS AND TESTING - CONTROL
CIRCUIT TEST
The starter control circuit has:
²Starter motor with integral solenoid
²Starter relay
²Transmission range sensor, or Park/Neutral
Position switch with automatic transmissions
²Ignition switch
²Battery
²All related wiring and connections
²Powertrain Control Module (PCM)
CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.²To disable ignition and fuel systems, disconnect
the Automatic Shutdown Relay (ASD). The ASD relay
is located in the Power Distribution Center (PDC).
Refer to the PDC cover for the proper relay location.
STARTER SOLENOID
WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN THE PARK POSITION WITH THE
PARKING BRAKE APPLIED.
(1) Verify battery condition. Battery must be in
good condition with a full charge before performing
any starter tests. Refer to Battery Tests.
(2) Perform Starter Solenoid test BEFORE per-
forming the starter relay test.
8F - 30 STARTINGRS
STARTING (Continued)
ProCarManuals.com