2002 CHRYSLER CARAVAN sensor

Remove the starter relay from the PDC as
described in this group to perform the following tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.
(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75  5 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.
(3) Connect a battery B+ lead to terminals 86 and
a ground lead to terminal 85 to energize the relay.
The relay should click. Also test for continuity
between terminals 30 and 87, and no continuity
between terminals 87A and 30. If OK, refer to Relay
Circuit Test procedure. If not OK, replace the faulty
relay.CAV FUNCTION
30 B (+)
85 P/N POSITION SW.SENSE
86 IGNITION SWITCH OUTPUT
87 STARTER RELAY OUTPUT
87A NO CONNECT
RELAY CIRCUIT TEST
(1) The relay common feed terminal cavity (30) is
connected to battery voltage and should be hot at all
times. If OK, go to Step 2. If not OK, repair the open
circuit to the PDC fuse as required.
(2) The relay normally closed terminal (87A) is
connected to terminal 30 in the de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) is con-
nected to the common feed terminal (30) in the ener-
gized position. This terminal supplies battery voltage
to the starter solenoid field coils. There should be
continuity between the cavity for relay terminal 87
and the starter solenoid terminal at all times. If OK,
go to Step 4. If not OK, repair the open circuit to the
starter solenoid as required.
(4) The coil battery terminal (86) is connected to
the electromagnet in the relay. It is energized when
the ignition switch is held in the Start position and
the clutch pedal is depressed (manual trans). Check
for battery voltage at the cavity for relay terminal 86
with the ignition switch in the Start position and the
clutch pedal is depressed (manual trans), and no
voltage when the ignition switch is released to the
On position. If OK, go to Step 5. If not OK, check for
an open or short circuit to the ignition switch and
repair, if required. If the circuit to the ignition switch
is OK, see the Ignition Switch Test procedure in this
group.
(5) The coil ground terminal (85) is connected to
the electromagnet in the relay. It is grounded
through the transmission range sensor only when the
gearshift selector lever is in the Park or Neutral
positions. Check for continuity to ground at the cav-
ity for relay terminal 85. If not OK with an auto-
matic transmission, check for an open or short circuit
to the transmission range sensor and repair. It is
grounded by the PCM if the conditions are right to
start the car. For automatic trans. cars the PCM
must see Park Neutral switch and near zero engine
rpm. For manual trans. cars the PCM only needs to
see near zero engine rpm. To diagnose the Park Neu-
tral switch of the trans range sensor refer to the
transaxle section for more information. Check for
continuity to ground while the ignition switch is in
the start position. If not OK and the vehicle has an
automatic trans. verify Park Neutral switch opera-
Starter Relay Pinout
Starter Relay Pinout
8F - 32 STARTINGRS
STARTING (Continued)
ProCarManuals.com

tion. If that checks OK check for continuity between
PCM and the terminal 85. Repair open circuit as
required. If OK, the PCM may be defective.
SAFETY SWITCHES
For diagnostics of the Transmission Range Sensor,
refer to the Transaxle section for more information.
If equipped with Clutch Interlock/Upstop Switch,
refer to Diagnosis and Testing in the Clutch section.
IGNITION SWITCH
After testing starter solenoid and relay, test igni-
tion switch and wiring. Refer to the Ignition Section
or Wiring Diagrams for more information. Check all
wiring for opens or shorts, and all connectors for
being loose or corroded.
BATTERY
For battery diagnosis and testing, refer to the Bat-
tery section for procedures.
ALL RELATED WIRING AND CONNECTORS
Refer to Wiring Diagrams for more information.
DIAGNOSIS AND TESTING - FEED CIRCUIT
RESISTANCE TEST
Before proceeding with this operation, review Diag-
nostic Preparation and Starter Feed Circuit Tests.
The following operation will require a voltmeter,
accurate to 1/10 of a volt.
CAUTION: Ignition and Fuel systems must be dis-
abled to prevent engine start while performing the
following tests.
(1) To disable the Ignition and Fuel systems, dis-
connect the Automatic Shutdown Relay (ASD). The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location.
(2) Gain access to battery terminals.
(3) With all wiring harnesses and components
properly connected, perform the following:
(a) Connect the negative lead of the voltmeter to
the battery negative post, and positive lead to the
battery negative cable clamp. Rotate and hold the
ignition switch in the START position. Observe the
voltmeter. If voltage is detected, correct poor con-
tact between cable clamp and post.
(b) Connect positive lead of the voltmeter to the
battery positive post, and negative lead to the bat-
tery positive cable clamp. Rotate and hold the igni-
tion switch key in the START position. Observe the
voltmeter. If voltage is detected, correct poor con-
tact between the cable clamp and post.(c) Connect negative lead of voltmeter to battery
negative terminal, and positive lead to engine
block near the battery cable attaching point.
Rotate and hold the ignition switch in the START
position. If voltage reads above 0.2 volt, correct
poor contact at ground cable attaching point. If
voltage reading is still above 0.2 volt after correct-
ing poor contacts, replace ground cable.
(4) Connect positive voltmeter lead to the starter
motor housing and the negative lead to the battery
negative terminal. Hold the ignition switch key in
the START position. If voltage reads above 0.2 volt,
correct poor starter to engine ground.
(a) Connect the positive voltmeter lead to the
battery positive terminal, and negative lead to bat-
tery cable terminal on starter solenoid. Rotate and
hold the ignition switch in the START position. If
voltage reads above 0.2 volt, correct poor contact at
battery cable to solenoid connection. If reading is
still above 0.2 volt after correcting poor contacts,
replace battery positive cable.
(b) If resistance tests do not detect feed circuit
failures, replace the starter motor.
DIAGNOSIS AND TESTING - FEED CIRCUIT
TEST
NOTE: The following results are based upon the
vehicle being at room temperature.
The following procedure will require a suitable
volt-ampere tester (Fig. 3).
CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.
(1) Check battery before performing this test. Bat-
tery must be fully charged.
(2) Connect a volt-ampere tester to the battery ter-
minals. Refer to the operating instructions provided
with the tester being used.
Fig. 3 Volt Ampere Tester
RSSTARTING8F-33
STARTING (Continued)
ProCarManuals.com

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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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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(9) Remove the lower oil dip stick tube bolt (Fig.
9).
(10) Remove wiring harness from the oil dip stick
tube
(11) Remove the 3 mounting bolts.
(12) Lower vehicle.
(13) Remove oil dip stick tube from vehicle.
(14) Roll and remove the generator from vehicle
(Fig. 10).REMOVAL - 3.5L
(1) Disconnect the negative battery cable.
(2) Turn wheels to the right.
(3) Raise and support the vehicle.
(4) Remove the right front tire.
(5) Remove the front axle nut.
(6) Relocate the ABS sensor (Fig. 11) wiring from
bracket (Fig. 12).
Fig. 9 DIP STICK LOWER BOLT
Fig. 10 GENERATOR 3.3/3.8L
Fig. 11 ABS WIRING AND STRUT
Fig. 12 ABS WIRING AND STRUT
8Fa - 26 CHARGINGRG
GENERATOR (Continued)
ProCarManuals.com

(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)
ProCarManuals.com

INSTALLATION
(1) Install the Generator Decoupler to the genera-
tor shaft.
(2) Use Special Tool #8433 (Fig. 20) to tighten the
Generator Decoupler (Fig. 21). Refer to the torque
chart for the proper torque.
(3) Install the Air Box, refer to the Engine section
for more information.
(4) Raise vehicle and support.
(5) Install accessory drive belt, refer to the Cooling
System section for proper procedures (Fig. 18).
(6) Install the right front lower splash shield.
(7) Lower vehicle.
(8) Connect battery negative cable.
VOLTAGE REGULATOR
DESCRIPTION
The Electronic Voltage Regulator (EVR) is not a
separate component. It is actually a voltage regulat-
ing circuit located within the Powertrain Control
Module (PCM). The EVR is not serviced separately. If
replacement is necessary, the PCM must be replaced.
OPERATION
The amount of DC current produced by the gener-
ator is controlled by EVR circuitry contained within
the PCM. This circuitry is connected in series with
the generators second rotor field terminal and its
ground.
Voltage is regulated by cycling the ground path to
control the strength of the rotor magnetic field. The
EVR circuitry monitors system line voltage (B+) and
calculated battery temperature or inlet air tempera-
ture sensor (refer to Inlet Air Temperature Sensor, if
equipped, for more information ). It then determines
a target charging voltage. If sensed battery voltage is
lower than the target voltage, the PCM grounds the
field winding until sensed battery voltage is at the
target voltage. A circuit in the PCM cycles the
ground side of the generator field at 250 times per
second (250Hz), but has the capability to ground the
field control wire 100% of the time (full field) to
achieve the target voltage. If the charging rate can-
not be monitored (limp-in), a duty cycle of 25% is
used by the PCM in order to have some generator
output. Also refer to Charging System Operation for
additional information.
Fig. 21 DECOUPLER INSTALLATION (Litens)
8Fa - 30 CHARGINGRG
GENERATOR DECOUPLER PULLEY (Continued)
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