2003 CHRYSLER CARAVAN instrument panel

OPERATION
The temperature sensor is a NTC thermistor.
When the temperature of the seat cushion cover
rises, the resistance of the sensor decreases. The
heated seat module supplies a five-volt current to one
side of each sensor, and monitors the voltage drop
through the sensor on a return circuit. The heated
seat module uses this temperature sensor input to
monitor the temperature of the seat, and regulates
the current flow to the seat heating elements accord-
ingly.
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Disconnect and isolate the battery negative
cable. Disconnect the green 4-way heated seat mod-
ule wire harness connector.
(2) Using an ohmmeter, check the resistance
between cavities 2 and 3. The sensor resistance
should be between 50 kilohms at 15É C (60É F) and 2
kilohms at 30É C (85É F). If not OK, replace the
faulty seat element and sensor assembly.
PASSENGER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are mounted in the
instrument panel center bezel (Fig. 6). The two three-
position rocker-type switches, one switch for each
front seat, are incorporated into one large switch
assembly that also includes the hazard, rear window
wiper and washer switches. The heated seat switches
each provide a resistor multiplexed signal to its
respective Heated Seat Module (HSM) through sepa-
rate hard wired circuits. Each switch has an Off,
Low, and High position so that both the driver and
the front seat passenger can select a preferred seat
heating mode. Each switch has two Light-Emitting
Diodes (LED) which light to indicate that the heater
for the seat is turned on.
The heated seat switches and their LEDs cannot
be repaired. If either switch or LED is faulty or dam-
aged, the entire switch assembly must be replaced.
OPERATION
There are three positions that can be selected with
each of the heated seat switches: Off, Low, or High.
When the left side of the switch rocker is fully
depressed, the Low position is selected and the low
position LED indicator illuminates. When the right
side of the switch rocker is fully depressed, the High
position is selected and the high position LED indi-
Fig. 5 HEATING ELEMENT INSTALLED - TYPICAL
1 - SEAT BACK WIRE HARNESS
2 - HEATED SEAT WIRE HARNESS CONNECTOR
3 - HEATED SEAT CUSHION ELEMENT
Fig. 6 HEATED SEAT SWITCH LOCATION
1 - HEATED SEAT SWITCHES
8G - 12 HEATED SEAT SYSTEMRS
HEATED SEAT SENSOR (Continued)
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cator illuminates. When the switch rocker is moved
to its neutral position (middle), Off is selected and
both LED indicators are extinguished.
Each switch provides separate resistor multiplexed
hard wire inputs to its respective Heated Seat Mod-
ule (HSM) to indicate the selected switch position.
The heated seat module responds to the heated seat
switch status messages by controlling the output to
the seat heater elements of the selected seat. The
Low heat position set point is about 36É C (97É F),
and the High heat position set point is about 41É C
(105É F).
DIAGNOSIS AND TESTING - PASSENGER
HEATED SEAT SWITCH
For complete circuit diagrams, refer toWiring
Diagrams.
WARNING: REFER TO THE RESTRAINTS SECTION
OF THIS MANUAL BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, SEAT OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
CHECKING SWITCH SIGNAL AND WIRING AT THE
MODULE
(1) Disconnect and isolate the battery negative
cable.
(2) Access and disconnect the gray 4-way connector
from the heated seat module. Visually inspect wiring
terminals for damage that would prevent positive
connection. If not OK, repair or replace the necessary
components.
(3) Reconnect the negative battery cable and Turn
heated seat ON in the LO position. Using an Ohm-
meter, check the resistance between cavities 2 and 3
of the gray connector noted above. Resistance should
be about 3.5 kiloohms (3500 ohms). If not OK, check
resistance directly at switch, as noted below. If OK,
proceed. If NOT OK replace the switch or faulty wir-
ing.
(4) Turn heated seat ON in the HI position. Using
an Ohmmeter, check the resistance between cavities
2 and 3 of the gray connector noted above. Resistance
should be about 1.4 kiloohms (1400 ohms). If not OK,
check resistance directly at switch, as noted below. If
OK, proceed. If NOT OK replace the switch or faulty
wiring.
(5) With the system ON in the HI position, Check
for battery voltage and ground at cavities 4 and 1. If
OK, proceed with testing remaining components. If
NOT OK, repair open or wiring short.
CHECKING SWITCH ONLY
(1) Disconnect and isolate the battery negative
cable. Remove the center bezel from the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - REMOV-
AL). Check for continuity between the ground circuit
cavity (#10) of the instrument panel switch bank
electrical connector and a good ground. There should
be continuity. If OK, go to Step 2. If not OK, repair
the open ground circuit to ground as required.
(2) Reconnect the battery negative cable. Turn the
ignition switch to the On position. Check for battery
voltage at the fused ignition switch output (run) cir-
cuit cavity of the instrument panel switch bank con-
nector (#4). If OK, turn the ignition switch to the Off
position, and go to Step 3. If not OK, repair the open
fused ignition switch output (run) circuit as required.
(3) Test the heated seat switch as shown in the
Heated Seat Switch Test chart and the connector pin-
out below (Fig. 7). If OK, go to Step 4. If not OK,
replace the faulty switch bank assembly.
PASSENGER HEATED SEAT SWITCH TEST
SWITCH
POSITIONRESISTANCE
BETWEENRESISTANCE
(OHMS)
Off Pin3&4OPEN
Low Pin3&43570
High Pin3&41430
All resistance values are  1%.
Fig. 7 Instrument Panel Switch Bank Connector
RSHEATED SEAT SYSTEM8G-13
PASSENGER HEATED SEAT SWITCH (Continued)
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(4) Reconnect the instrument panel switch bank
and test the heated seat system for proper operation.
If the system is still inoperative proceed with check-
ing remaining components.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO THE RESTRAINTS SECTION OF
THIS MANUAL BEFORE ATTEMPTING ANY STEER-
ING WHEEL, STEERING COLUMN, SEAT OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel center bezel.
Refer toInstrument Panel Center Bezelin the
Body section for the procedure.
(3) Remove the three screws (Fig. 8) that secure
the heated seat switch to the back of the instrument
panel center bezel.
(4) Remove the heated seat switch from the back
of the instrument panel center bezel.
INSTALLATION
(1) Position the heated seat switch onto the back
of the instrument panel center bezel.
(2) Install and tighten the three screws that secure
the heated seat switch to the back of the instrumentpanel center bezel (Fig. 8). Tighten the screws to 1.5
N´m (13 in. lbs.).
(3) Install the center bezel onto the instrument
panel. Refer toInstrument Panel Center Bezelin
the Body section for the procedure.
(4) Reconnect the battery negative cable.
Fig. 8 SWITCH RETAINING SCREWS
1 - HEATED SEAT SWITCH ASSEMBLY
2 - RETAINING SCREWS
8G - 14 HEATED SEAT SYSTEMRS
PASSENGER HEATED SEAT SWITCH (Continued)
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HORN
TABLE OF CONTENTS
page page
HORN SYSTEM
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING - HORN SYSTEM . . . 1
HORN
DIAGNOSIS AND TESTING - HORN..........3
REMOVAL.............................5INSTALLATION..........................5
HORN RELAY
DIAGNOSIS AND TESTING - HORN RELAY....5
REMOVAL.............................5
INSTALLATION..........................5
HORN SWITCH
DESCRIPTION..........................5
HORN SYSTEM
DESCRIPTION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAG, REFER TO ELECTRICAL, RESTRAINTS FOR
SAFETY PRECAUTIONS. DISCONNECT THE NEGA-
TIVE CABLE FROM THE BATTERY BEFORE SER-
VICING COMPONENTS INVOLVING THE AIRBAG
SYSTEM. ACCIDENTAL DEPLOYMENT OF AIRBAG
AND PERSONAL INJURY CAN RESULT.
The horn circuit consists of a horn switch, clock-
spring, horn relay, horns and Integrated Power Mod-
ule (IPM). The horn switch is a membrane switch
located in the airbag trim cover. The horns are
located forward of the left front wheel behind the
bumper fascia.
OPERATION
The horn relay plugs into the Integrated Power
Module (IPM) which is located in the engine com-
partment. For circuit information and component
locations, refer to the appropriate wiring information.
The wiring information includes wiring diagrams,
proper wire and connector repair procedures, details
of wire harness routing and retention, connector pin-
out information and location views for the various
wire harness connectors, splices and grounds.
The horns will not function if the switch is
ªCLOSEDº for more than 30 seconds. Once the
switch is ªOPENº, a 20±30 second delay will occur
before the horns are functional again.
DIAGNOSIS AND TESTING - HORN SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO ELECTRICAL, RESTRAINTS
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
Refer to Horn System Test below. If the horn does
not sound, check horn fuse located in the Integrated
Power Module (IPM). If the fuse is blown, replace
with the correct fuse. If the horns fail to sound and
the new fuse blows when depressing the horn switch,
a short circuit in the horn or the horn wiring
between the fuse terminal and the horn is responsi-
ble, or a defective horn switch allowed the horn to
burn out is responsible.
If the fuse is OK, test horn relay (Refer to 8 -
ELECTRICAL/HORN/HORN RELAY - DIAGNOSIS
AND TESTING).
If the relay is OK, test horn. Refer to Horn System
Test.
CAUTION: Continuous sounding of horn may
cause horn failure.
Should the horn sound continuously:
²Unplug the horn relay from IPM.
²Refer to (Refer to 8 - ELECTRICAL/HORN/
HORN RELAY - DIAGNOSIS AND TESTING).
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
RSHORN8H-1
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INSTRUMENT CLUSTER DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
INSTRUMENT CLUSTER
INOPERATIVE. NO
RESPONSE FROM
INSTRUMENT CLUSTER.NO PCI BUS MESSAGES
FROM THE BCM.USE A DRB IIITSCAN TOOL TO CHECK THE BCM.
IF OK, LOOK FOR ANOTHER POSSIBLE CAUSE
FOR CLUSTER FAILURE. IF NOT OK, REFER TO
THE PROPER BODY DIAGNOSTIC PROCEDURES
MANUAL.
SPREAD TERMINAL(S)
ON WIRING HARNESS
CLUSTER CONNECTOR.REMOVE CLUSTER FROM INSTRUMENT PANEL
AND CHECK WIRING HARNESS CONNECTOR FOR
SPREAD TERMINAL. IF OK, LOOK FOR ANOTHER
POSSIBLE CAUSE FOR THE CLUSTER FAILURE. IF
NOT OK, REPAIR CONNECTOR.
BCM IS NOT RECEIVING
PROPER INPUT FROM
THE IGNITION SWITCH.1. USE A DRB IIITSCAN TOOL TO VERIFY IGNITION
SWITCH STATUS INTO THE BCM. IF NOT OK, GO
TO STEP (2). IF OK, LOOK AT ANOTHER POSSIBLE
CAUSE OF FAILURE.
2. CHECK IGNITION SWITCH FUNCTION AND
WIRING.
INTERNAL CLUSTER
FAILURE.REPLACE CLUSTER.
WAKE UP CIRCUIT
FAULTY.VERIFY CONTINUITY OF WAKE UP CIRCUIT FROM
BCM TO MIC. CIRCUIT SHALL BE LOW WHENEVER
BCM IS AWAKE.
POWER OR GROUND
MISSING.IF NO RESPONSE FROM THE MIC, CHECK FOR
POWER AND GROUND AT THE MIC CONNECTOR.
REFER TO WIRING DIAGRAMS FOR CONNECTOR
CALL OUTS.
RSINSTRUMENT CLUSTER8J-3
INSTRUMENT CLUSTER (Continued)
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SPEEDOMETER DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO POINTER
MOVEMENT.1. INTERNAL CLUSTER
FAILURE.1.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST AND
CHECK FOR FAULT CODES.
²IF SPEEDOMETER POINTER MOVES TO CALIBRATION
POINTS DURING TEST LOOK FOR ANOTHER POSSIBLE
CAUSE OF FAILURE.
²IF THE POINTER DOESN'T MOVE DURING TEST,
CHECK FOR POWER AND GROUND TO THE MIC. IF
POWER AND GROUND ARE PRESENT GO TO STEP 1.B.
1.B. REPLACE CLUSTER. GO TO STEP 1.C.
1.C. CONNECT CLUSTER INTO INSTRUMENT PANEL
WIRING HARNESS. PLACE IT BACK INTO THE PROPER
POSITION IN THE INSTRUMENT PANEL. PUT IN THE
TOP FOUR MOUNTING SCREWS AND SECURE THE
CLUSTER TO THE INSTRUMENT PANEL.
2. NO SPEED PCI BUS
MESSAGE OR ZERO
MPH PCI SPEED BUS
MESSAGE.2.A. CHECK THE PCM (CODE 10) USING A DRB IIIT
SCAN TOOL. IF OK, GO TO STEP 2.B. IF NOT OK,
REFER TO THE PROPER POWERTRAIN DIAGNOSTIC
PROCEDURES MANUAL TO REPAIR THE PCM.
2.B. CHECK THE SPEED SIGNAL INPUT INTO THE PCM.
THE SPEED SIGNAL ORIGINATES FROM THE TCM FOR
VEHICLES WITH THE 4 SPEED ELECTRONIC
TRANSMISSIONS. CHECK CONTINUITY FROM TCM TO
PCM. IF OK, USE A DRB IIITSCAN TOOL TO CHECK
TCM. REFER TO THE PROPER TRANSMISSION
DIAGNOSTIC PROCEDURES MANUAL TO REPAIR THE
TCM. IF NOT OK, REPAIR WIRING.
8J - 4 INSTRUMENT CLUSTERRS
INSTRUMENT CLUSTER (Continued)
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ELECTRONIC GEAR INDICATOR DISPLAY DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO DISPLAY. 1. INTERNAL CLUSTER
FAILURE.1. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK FOR FAULT CODES.
²IF PRND3L (PRND1234 IF AUTOSTICK
EQUIPPED) PASSES THE SEGMENT CHECK, THEN
FAILURE MAY NOT BE IN THE CLUSTER. LOOK
FOR ANOTHER POSSIBLE CAUSE OF FAILURE. IF
IT FAILS, REPLACE CLUSTER ASSEMBLY.
ERRATIC DISPLAY. 1. INTERNAL CLUSTER
FAILURE.1. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK FOR FAULT CODES.
²IF PRND3L (PRND1234 IF AUTOSTICK
EQUIPPED) PASSES THE SEGMENT CHECK, THEN
FAILURE MAY NOT BE IN THE CLUSTER. LOOK
FOR ANOTHER POSSIBLE CAUSE OF FAILURE.
2. BAD PCI BUS
MESSAGE FROM THE
TCM.2. USE A DRB IIITSCAN TOOL TO CHECK THE
TCM. REFER TO THE PROPER TRANSMISSION
DIAGNOSTIC PROCEDURES MANUAL TO
PROPERLY DIAGNOSE AND REPAIR.
ALL SEGMENTS ARE ON. 1. NO PCI BUS
MESSAGE FROM THE
TCM.1.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST.
IF PRND3L (PRND1234 IF AUTOSTICK EQUIPPED)
PASSES TEST GO TO STEP 1.B. IF PRND3L
(PRND1234 IF AUTOSTICK EQUIPPED) FAILS TEST,
REPLACE CLUSTER ASSEMBLY.
1.B. CHECK THE TCM USING A DRB IIITSCAN
TOOL. REFER TO THE PROPER TRANSMISSION
DIAGNOSTIC PROCEDURES MANUAL TO
PROPERLY DIAGNOSE AND REPAIR.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove Over Steering Column Bezel by lifting
it straight up with a firm pull.
(3) Remove the four cluster bezel attaching screws.
(4) Tilt the steering column in the full down posi-
tion.
(5) Pull rearward on the cluster bezel and remove.
(6) Remove the four screws holding instrument
cluster to instrument panel.
(7) Rotate top of cluster outward.
(8) Disconnect the cluster harness connector.
(9) Remove instrument cluster from instrument
panel.
INSTALLATION
(1) Connect the instrument cluster wire connector.
(2) Rotate top of cluster inward as placing into
instrument panel opening.
(3) Install the four screws holding instrument clus-
ter to instrument panel.
(4) Position cluster bezel into place.(5) Install the four bezel attaching screws.
(6) Install the Over Steering Column Bezel by
firmly snapping into place.
(7) Connect the battery negative cable.
CLUSTER LENS
REMOVAL
(1) Remove the instrument cluster. Refer to Elec-
trical, Instrument Cluster, Removal.
(2) Remove the screws holding the lens to the
instrument cluster.
(3) Press down on the snap features of the lens
and remove the lens from the cluster.
INSTALLATION
(1) Insert the lens snap features into the cluster.
(2) Install the screws holding the lens to the
instrument cluster.
(3) Install the instrument cluster. Refer to Electri-
cal, Instrument Cluster, Installation.
8J - 10 INSTRUMENT CLUSTERRS
INSTRUMENT CLUSTER (Continued)
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(Dome Lamp, Daytime Brightness, Dimming Level or
Off). The third wire is a dedicated signal return
(ground) wire. The fourth wire provides power to the
front fog lamp indicator.
HEADLAMP TIME DELAY SYSTEM
The headlamp time delay system is controlled by
the Body Control Module (BCM) via a PCI bus mes-
sage transmitted by the BCM to the FCM to turn off
the headlamps.
OPERATION
AUTOMATIC HEADLAMP SYSTEM
Automatic headlamps are controlled by the Body
Control Module (BCM). With the headlamp switch in
the AUTO position, the BCM will control the head-
lamp, parking, side marker, tail and instrumentation
lamps based on ambient light levels. Ambient light
levels are monitored by the BCM using the Day/
Night signal and Electrochromatic Mirror (ECM)
present from the Compass Mini Trip (CMTC) located
on the front windshield in front of the rear view mir-
ror ECM. Ambient light readings are averaged to
limit cycling the lamps ON and OFF when passing
through areas with varying light levels. The auto-
matic headlamps will only function when the engine
is running with RPM > 450. When the headlamp
switch is in the AUTO position (Automatic mode), the
Headlamp Time Delay system will function when the
ignition switch is placed in any position other than
run/start.
DAYTIME RUNNING LAMPS
Power is reduced using pulse-width modulation to
the high beams, where by the power is switched on
and off rapidly instead of remaining on continuously.
The duration and interval of the power pulses is pro-
grammed into the FCM.
HEADLAMP SYSTEM
The headlamp system will default to headlamps
ON position when ignition switch is ON and when an
open or short circuit failure occurs on the headlamp
switch input or PCI data bus communication between
the BCM and the FCM fails. The system will return
to normal operation when the open or short is
repaired. A fault will be reported by the BCM when a
failure occurs on the dimmer or headlamp switch
input.
If the exterior lamps are ON and the headlamp
switch is in any position other than OFF or AUTO
and with the ignition switch OFF (LOCK) after 3
minutes the BCM sends a message via PCI bus tothe FCM informing the FCM to turn off the head-
lamps, park lamps and fog lamps. This feature pre-
vents the vehicle battery from being discharged when
the vehicle lights have been left ON.
HEADLAMP TIME DELAY SYSTEM
The headlamp time delay system is activated by
turning the headlamps ON (high or low beam) while
the engine is running, turning the ignition switch
OFF, and then turning the headlamp switch OFF
within 45 seconds. The system will not activate if
more than 45 seconds elapse between ignition switch
OFF and headlamp switch OFF. The BCM will allow
the headlamps to remain ON for 90 seconds (config-
urable) before they automatically turn off (If the key
is in the ignition during the headlamp time delay
mode, then both the headlamps and park lamps
(including panel dimming) will be ON). Refer to the
Owner's Manual for more information.
If the headlamp switch is in the Auto Headlamp
Position, the headlamps are ON due to the night sig-
nal from the CMTC and the ignition switch is in any
position other than run/start, the BCM shall enter a
90 second (configurable) Auto Headlamps time delay
mode. If the key is in the ignition during the head-
lamp time delay mode, then both the headlamps and
park lamps (including panel dimming) will be ON. If
the key is not in the ignition, then only the head-
lamps will be ON. The BCM will allow the head-
lamps to remain ON for 90 seconds before they
automatically turn OFF. Refer to the Owner's Man-
ual for more information.
OPTICAL HORN/HIGH BEAMS
When the multi-function switch is pulled to the
first detent (optical horn) signal, the headlamps are
ON, key-in the ignition the BCM shall send a mes-
sage via PCI bus to the FCM to turn on the head-
lamps drivers to illuminate all four filaments (Low
and High beams). When the multi-function switch is
pulled to the second detent (high beam) signal and
the headlamps are ON, the BCM shall send a mes-
sage via PCI bus to the FCM to turn on the head-
lamps drivers. The High Beams are illuminated and
the Low Beams and Fog Lamps (if ON) are extin-
guished. If the headlamps were in the high beam
configuration when power was removed from the
headlamps, the headlamps will be configured as low
beam the next time they are activated.
NOTE: For RG - Export vehicles, the low beams and
front fog lamps will remain ON when high beams
are activated.
RSLAMPS/LIGHTING - EXTERIOR8L-3
LAMPS/LIGHTING - EXTERIOR (Continued)
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