2002 CHRYSLER CARAVAN engine

REMOVAL
The battery cables on this model may include por-
tions of wiring circuits for the generator and other
components on the vehicle. If battery cable replace-
ment is required, it will be necessary to extract the
cables out of the engine wire harness assembly. Use
care not to damage the other wires and circuits
which are also packaged into the engine wire harness
assembly.
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Disconnect and isolate the negative battery
cable terminal.(3) Remove the battery thermowrap (if equipped)
from the battery tray.
(4) Remove the tape from the engine wire harness
assembly, to access the desired battery cable.
(5) One at a time, trace and disconnect the battery
cable retaining fasteners and routing clips until the
desired cable is free from the vehicle.
(6) Feed the battery cable out of the vehicle.
INSTALLATION
(1) Position the battery cable in the vehicle.
(2) One at a time, trace and install the battery
cable retaining fasteners and routing clips until the
desired cable is properly installed in the engine wire
harness assembly.
(3) Install the tape on the engine wire harness
assembly.
(4) Install the battery thermowrap (if equipped) on
the battery tray.
(5) Connect the negative battery cable terminal.
BATTERY TRAY
DESCRIPTION
The battery is mounted in a molded plastic battery
tray and support unit located in the left front corner
of the engine compartment. The battery tray and
support unit is secured with two nuts, one is located
Fig. 15 TEST BATTERY POSITIVE CABLE
RESISTANCE - TYPICAL
1 - BATTERY
2 - VOLTMETER
3 - STARTER MOTOR
Fig. 16 TEST GROUND CIRCUIT RESISTANCE -
TYPICAL
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
Fig. 17 RS BATTERY TRAY
1 - ENGINE VACUUM RESERVOIR
2 - BATTERY TRAY ASSEMBLY
3 - DRAINAGE HOSE
8Fa - 18 BATTERY SYSTEMRG
BATTERY CABLES (Continued)
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directly under the battery and the other is located on
the right side of the tray which also serves as a cool-
ant bottle neck retaining bolt. An additional bolt is
located directly under the battery.
The battery tray and support unit also includes a
engine vacuum reservoir, located in the rear of the
unit (Fig. 17). And a drainage hose, located in the
front of the unit (Fig. 17).
OPERATION
The battery tray provides a secure mounting loca-
tion and supports the battery. The battery tray also
provides the anchor point for the battery holddown
hardware. The battery tray and the battery hold-
down hardware combine to secure and stabilize the
battery in the engine compartment, which prevents
battery movement during vehicle operation. Unre-
strained battery movement during vehicle operation
could result in damage to the vehicle, the battery, or
both.
The battery tray used on this model also includes a
engine vacuum reservoir and drainage hose. The vac-
uum reservoir provides a storage container for engine
vacuum. Refer to the engine section of the service
manual for more engine vacuum information. The
drainage hose provides means for any liquid that
might collect in the bottom of the battery tray to
drain under the vehicle.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the battery from the vehicle. Refer to
the procedure in this section.
(3) Remove the battery tray retaining fasteners
(Fig. 18).
(4) Pull battery tray up far enough to disconnect
the engine vacuum harness hose from the battery
tray mounted, vacuum reservoir.
(5) Remove the battery tray from the vehicle.
INSTALLATION
(1) Position the battery tray in the vehicle.
(2) Connect the engine vacuum harness hose on
the battery tray mounted vacuum reservoir.
(3) Position drainage hose and install the battery
tray retaining fasteners (Fig. 18).
(4) Install the battery in the vehicle. Refer to the
procedure in this section.
(5) Connect the negative battery cable.
THERMOWRAP
DESCRIPTION
A one-piece slip-on thermowrap unit shields the
battery case from engine compartment heat. The
thermowrap slips over the battery case and due to its
one piece design, the battery cables must be removed
in order to install or remove the thermowrap.
OPERATION
The thermowrap protects the battery from engine
compartment temperature extremes. The tempera-
ture of the battery can affect battery life. The air
trapped in the padded material of the thermowrap
creates a dead air space, which helps to insulate the
sides of the battery case from the air temperature
found in the surrounding engine compartment.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Disconnect the positive battery cable.
(3) Lift the battery thermowrap straight up to
remove from the battery.
INSTALLATION
(1) Position the thermowrap on the battery.
(2) Connect the negative and positive battery
cables.
Fig. 18 BATTERY TRAY POSITION & ORIENTATION
1 - BATTERY TRAY RETAINING FASTENERS
RGBATTERY SYSTEM8Fa-19
BATTERY TRAY (Continued)
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CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION - CHARGING SYSTEM.......20
OPERATION - CHARGING SYSTEM.........20
DIAGNOSIS AND TESTING - ON-BOARD
DIAGNOSTIC SYSTEM.................21
SPECIFICATIONS
GENERATOR........................22
TORQUE............................22
SPECIAL TOOLS.......................22
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................23
OPERATION...........................23
REMOVAL.............................23
GENERATOR
DESCRIPTION.........................23
OPERATION...........................23
REMOVAL
REMOVAL - 2.4L......................23REMOVAL - 2.5L......................24
REMOVAL - 3.3/3.8L...................25
REMOVAL - 3.5L......................26
INSTALLATION
INSTALLATION - 2.4L..................27
INSTALLATION - 2.5L..................28
INSTALLATION - 3.3/3.8L................28
INSTALLATION - 3.5L..................28
GENERATOR DECOUPLER PULLEY
DESCRIPTION.........................28
OPERATION...........................28
DIAGNOSIS AND TESTING - GENERATOR
DECOUPLER PULLEY..................29
REMOVAL.............................29
INSTALLATION.........................30
VOLTAGE REGULATOR
DESCRIPTION.........................30
OPERATION...........................30
CHARGING
DESCRIPTION - CHARGING SYSTEM
The charging system consists of:
²Generator
²Decoupler Pulley (If equipped)
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM)
²Ignition switch (refer to the Ignition System sec-
tion for information)
²Battery (refer to the Battery section for informa-
tion)
²Inlet Air Temperature (calculated battery tem-
perature)
²Voltmeter (refer to the Instrument Cluster sec-
tion for information if equipped)
²Wiring harness and connections (refer to the
Wiring section for information)
²Accessory drive belt (refer to the Cooling section
for more information)
OPERATION - CHARGING SYSTEM
The charging system is turned on and off with the
ignition switch. The system is on when the engine is
running and the ASD relay is energized. The ASD
relay is energized when the PCM grounds the ASD
control circuit. This voltage is connected through the
PCM or IPM (intelligent power module) (if equipped)and supplied to one of the generator field terminals
(Gen. Source +) at the back of the generator.
The generator is driven by the engine through a
serpentine belt and pulley or decoupler pulley
arrangement.
The amount of DC current produced by the gener-
ator is controlled by the EVR (field control) circuitry
contained within the PCM. This circuitry is con-
nected in series with the second rotor field terminal
and ground.
An Inlet air temperature sensor is used to calcu-
late the temperature near the battery. This tempera-
ture data, along with data from monitored line
voltage (battery voltage sense circuit), is used by the
PCM to vary the battery charging rate. This is done
by cycling the ground path to control the strength of
the rotor magnetic field. The PCM then compensates
and regulates generator current output accordingly
to maintain system voltage at the targeted system
voltage based on battery temperature.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including EVR
(field control) circuitry, are monitored by the PCM.
Each monitored circuit is assigned a Diagnostic Trou-
ble Code (DTC). The PCM will store a DTC in elec-
tronic memory for certain failures it detects and
illuminate the (MIL) lamp. Refer to On-Board Diag-
nostics in the Electronic Control Modules(Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
8Fa - 20 CHARGINGRG
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ULES/POWERTRAIN CONTROL MODULE -
DESCRIPTION) section for more DTC information.
The Check Gauges Lamp (if equipped) or Battery
Lamp monitors:charging system voltage,engine
coolant temperature and engine oil pressure. If an
extreme condition is indicated, the lamp will be illu-
minated. The signal to activate the lamp is sent via
the PCI bus circuits. The lamp is located on the
instrument panel. Refer to the Instrument Cluster
section for additional information.
The PCM uses the inlet air temperature sensor to
control the charge system voltage. This temperature,
along with data from monitored line voltage, is used
by the PCM to vary the battery charging rate. The
system voltage is higher at cold temperatures and is
gradually reduced as the calculated battery tempera-
ture increases.
The ambient temperature sensor is used to control
the battery voltage based upon ambient temperature
(approximation of battery temperature). The PCM
maintains the optimal output of the generator by
monitoring battery voltage and controlling it to a
range of 13.5 - 14.7 volts based on battery tempera-
ture.
DIAGNOSIS AND TESTING - ON-BOARD
DIAGNOSTIC SYSTEM
The Powertrain Control Module (PCM) monitors
critical input and output circuits of the charging sys-
tem, making sure they are operational. A Diagnostic
Trouble Code (DTC) is assigned to each input and
output circuit monitored by the OBD system. Some
circuits are checked continuously and some are
checked only under certain conditions.
If the OBD system senses that a monitored circuit
is bad, it will put a DTC into electronic memory. The
DTC will stay in electronic memory as long as the
circuit continues to be bad. The PCM is programmed
to clear the memory after 50 engine starts if the
problem does not occur again.
DIAGNOSTIC TROUBLE CODES
A DTC description can be read using the DRBIIIt
scan tool. Refer to the appropriate Powertrain Diag-
nostic Procedures manual for information.
A DTC does not identify which component in a cir-
cuit is bad. Thus, a DTC should be treated as a
symptom, not as the cause for the problem. In some
cases, because of the design of the diagnostic test
procedure, a DTC can be the reason for another DTC
to be set. Therefore, it is important that the test pro-
cedures be followed in sequence, to understand what
caused a DTC to be set.ERASING DIAGNOSTIC TROUBLE CODES
The DRBIIItScan Tool must be used to erase a
DTC.
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp or battery lamp is illumi-
nated with the engine running
²the voltmeter (if equipped) does not register
properly
²an undercharged or overcharged battery condi-
tion occurs.
Remember that an undercharged battery is often
caused by:
²accessories being left on with the engine not
running
²a faulty or improperly adjusted switch that
allows a lamp to stay on. Refer to Ignition-Off Draw
Test (Refer to 8 - ELECTRICAL/BATTERY SYSTEM/
BATTERY - STANDARD PROCEDURE)
INSPECTION
The Powertrain Control Module (PCM) monitors
critical input and output circuits of the charging sys-
tem, making sure they are operational. A Diagnostic
Trouble Code (DTC) is assigned to each input and
output circuit monitored by the On-Board Diagnostic
(OBD) system. Some charging system circuits are
checked continuously, and some are checked only
under certain conditions.
Refer to Diagnostic Trouble Codes in; Powertrain
Control Module; Electronic Control Modules for more
DTC information. This will include a complete list of
DTC's including DTC's for the charging system.
To perform a complete test of the charging system,
refer to the appropriate Powertrain Diagnostic Proce-
dures service manual and the DRBIIItscan tool.
Perform the following inspections before attaching
the scan tool.
(1) Inspect the battery condition. Refer to the Bat-
tery section (Refer to 8 - ELECTRICAL/BATTERY
SYSTEM - DIAGNOSIS AND TESTING) for proce-
dures.
(2) Inspect condition of battery cable terminals,
battery posts, connections at engine block, starter
solenoid and relay. They should be clean and tight.
Repair as required.
(3) Inspect all fuses in both the fuseblock and
Power Distribution Center (PDC) for tightness in
receptacles. They should be properly installed and
tight. Repair or replace as required.
(4) Inspect generator mounting bolts for tightness.
Replace or tighten bolts if required. Refer to the Gen-
erator Removal/Installation section of this group for
torque specifications (Refer to 8 - ELECTRICAL/
CHARGING - SPECIFICATIONS).
RGCHARGING8Fa-21
CHARGING (Continued)
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(5) Inspect generator drive belt condition and ten-
sion. Tighten or replace belt as required. Refer to
Belt Tension Specifications(Refer to 7 - COOLING/
ACCESSORY DRIVE - SPECIFICATIONS).
(6) Inspect decoupler pulley (if equipped). Ensure
decoupler pulley is driving the alternator rotor.
(7) Inspect automatic belt tensioner (if equipped).
Refer to the Cooling System for more information.
(8) Inspect generator electrical connections at gen-
erator field, battery output, and ground terminal (if
equipped). Also check generator ground wire connec-
tion at engine (if equipped). They should all be clean
and tight. Repair as required.SPECIFICATIONS
GENERATOR
Type Engine Minimun Test
Amperage
Denso 2.4 L 125 Amp
Denso 3.3/3.8L 135 Amp or 145
Amp
Test Specification:
1. Engine RPM : 2500 RPM  20 RPM
2. Voltage Output : 14.0 V   0.5 V
3. Field Current : 5 amps   0.1 amps
Part number is located on the side of the generator.
TORQUE
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Battery Hold Down Clamp
Bolt20 14.7 180
Generator B+ Nut 12.4 9.2 110
Battery Terminal Nut 4 35
Generator Mounting Bolt
2.4L28.2 20.8 250
Generator Mounting Bolts
3.3/3.8L54.2 40
Starter Solenoid Battery
Nut 3.3/3.8L11.3 8.3 100
Generator Decoupler 109.8 81
SPECIAL TOOLS
GENERATOR DECOUPLER 8433
8Fa - 22 CHARGINGRG
CHARGING (Continued)
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BATTERY TEMPERATURE
SENSOR
DESCRIPTION
The PCM incorporates a Battery Temperature Sen-
sor (BTS) on its circuit board.
OPERATION
The PCM uses the temperature of the battery area
to control the charge system voltage. This tempera-
ture, along with data from monitored line voltage, is
used by the PCM to vary the battery charging rate.
The system voltage is higher at cold temperatures
and is gradually reduced as temperature around the
battery increases.
The ambient temperature sensor is used to control
the battery voltage based upon ambient temperature
(approximation of battery temperature). The PCM
maintains the optimal output of the generator by
monitoring battery voltage and controlling it to a
range of 13.5 - 14.7 volts based on battery tempera-
ture.
The battery temperature sensor is also used for
OBD II diagnostics. Certain faults and OBD II mon-
itors are either enabled or disabled depending upon
the battery temperature sensor input (example: dis-
able purge and EGR, enable LDP). Most OBD II
monitors are disabled below 20ÉF.
REMOVAL
The battery temperature sensor is not serviced sep-
arately. If replacement is necessary, the PCM must
be replaced.
GENERATOR
DESCRIPTION
The generator is belt-driven by the engine. It is
serviced only as a complete assembly. The generator
produces DC voltage at the B+ terminal. If the gen-
erator is failed, the generator assembly subcompo-
nents (generator and decoupler pulley) must be
inspected for individual failure and replaced accord-
ingly.
OPERATION
As the energized rotor begins to rotate within the
generator, the spinning magnetic field induces a cur-
rent into the windings of the stator coil. Once the
generator begins producing sufficient current, it also
provides the current needed to energize the rotor.
The Y type stator winding connections deliver the
induced AC current to 3 positive and 3 negative
diodes for rectification. From the diodes, rectified DC
current is delivered to the vehicles electrical system
through the generator, battery, and ground terminals.
Excessive or abnormal noise emitting from the gen-
erator may be caused by:
²Worn, loose or defective bearings
²Loose or defective drive pulley (2.4L) or decou-
pler (3.3/3.8L)
²Incorrect, worn, damaged or misadjusted drive
belt
²Loose mounting bolts
²Misaligned drive pulley
²Defective stator or diode
²Damaged internal fins
REMOVAL
REMOVAL - 2.4L
(1) Release hood latch and open hood.
(2) Disconnect battery negative cable.
(3) Disconnect the Inlet Air Temperature sensor.
(4) Remove the Air Box, refer to the Engine/Air
Cleaner for more information.
(5) Remove the EVAP Purge solenoid from its
bracket and reposition.
(6) Disconnect the push-in field wire connector
from back of generator.
(7) Remove nut holding B+ wire terminal to back
of generator.
(8) Separate B+ terminal from generator.
(9) Remove accessory drive belt, refer to the Cool-
ing System section for proper procedures.
(10) Remove the generator.
RGCHARGING8Fa-23
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REMOVAL - 2.5L
(1) Disconnect the negative battery cable (Fig. 1).
(2) Remove the engine cover (Fig. 2).(3) Raise vehicle and support.
(4) Turn wheels to the right. Remove the right
front splash shield (Fig. 3).
(5) Remove the generator drive belt (Fig. 4).
Fig. 1 BATTERY CONNECTION
Fig. 2 ENGINE COVER
Fig. 3 SPLASH SHIELD
Fig. 4 GENERATOR BELT
8Fa - 24 CHARGINGRG
GENERATOR (Continued)
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(5) Connect the push-in field wire connector to
back of generator.
(6) Install the EVAP Purge solenoid to its bracket.
(7) Install the Air Box, refer to the Engine/Air
Cleaner for more information.
(8) Connect the Inlet Air Temperature sensor.
(9) Connect battery negative cable.
INSTALLATION - 2.5L
(1) Install generator.
(2) Install the 2 lower mounting Bolts (Fig. 8).
(3) Install the Air Cleaner Box (Fig. 7).
(4) Install the upper support bracket (Fig. 6).
(5) Install the wiring harness on upper generator
bracket (Fig. 6).
(6) Connect the field connection (Fig. 5).
(7) Connect the generator battery connection (Fig.
5).
(8) Raise vehicle and support.
(9) Install the generator drive belt (Fig. 4).
(10) Install the right front splash shield (Fig. 3).
(11) Lower vehicle.
(12) Install the engine cover (Fig. 2).
(13) Connect the negative battery cable (Fig. 1).
INSTALLATION - 3.3/3.8L
(1) Roll and place generator in position on vehicle
(Fig. 10).
(2) Install upper bolts to hold generator in place.
(3) Lubricate the o-ring. Install oil dip stick tube.
(4) Install the upper oil dip stick tube bolt.
(5) Place B+ terminal in position on generator.
(6) Install nut to hold B+ wire terminal to back of
generator.
(7) Connect the push-in field wire connector into
back of generator.
(8) Raise vehicle and support.
(9) Install the lower mounting bolt and tighten.
(10) Install the lower oil dip stick tube bolt and
tighten (Fig. 9).
(11) Install accessory drive belt, refer to the Cool-
ing System section for proper procedures.
(12) Install the right front lower splash shield.
(13) Lower vehicle.
(14) Install wiring harness to the oil dip stick tube
(15) Connect battery negative cable.
(16) Verify generator output rate.
INSTALLATION - 3.5L
(1) Install generator (Fig. 16) and the 3 mounting
bolts and tighten.
(2) Connect the generator positive battery cable
(Fig. 15).
(3) Connect the field connector and lock the con-
nector (Fig. 15).
(4) Install the axle shaft to the transmission.(5) Install axle to steering knuckle (Fig. 13).
(6) Install the 2 upper clevies bolts and tighten,
refer to the Suspension section.
(7) Install axle nut and tighten, refer to the Differ-
ential and Driveline section.
(8) Relocate the ABS sensor wiring to bracket (Fig.
12).
(9) Install the accessory drive belt (Fig. 14), refer
to the Cooling section.
(10) Install the right front splash shield.
(11) Install the right front tire, refer to the Wheels
and Tires section.
(12) Lower vehicle.
(13) Connect the negative battery cable.
GENERATOR DECOUPLER
PULLEY
DESCRIPTION
The Generator Decoupler is a one way clutch (Fig.
17). It is attached to the generator and replaces the
standard pulley. It is a non-serviceable item and is to
be replaced as an assembly. It is a dry operation (no
grease or lubricants). The operation of it is not tem-
perature sensitive and has a low sensitivity to elec-
trical load.
OPERATION
The generator decoupler is a one way clutch and
should be replaced as an assembly. It is designed to
help reduce belt tension fluctuation, reduce fatigue
loads, improve belt life, reduce hubloads on compo-
nents, and reduce noise.
Fig. 17 GENERATOR DECOUPLER 3.3/3.8L
8Fa - 28 CHARGINGRG
GENERATOR (Continued)
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