2001 DODGE TOWN AND COUNTRY air condition

CONDITION POSSIBLE CAUSES CORRECTION
ERRATIC POINTER
MOVEMENT.1. BAD PCI BUS
MESSAGE FROM
PCM.1. CHECK THE PCM USING A DRB IIITSCAN TOOL.
REFER TO THE PROPER ENGINE DIAGNOSTIC
PROCEDURES MANUAL TO PROPERLY DIAGNOSE AND
REPAIR.
2. INTERNAL
CLUSTER FAILURE.2.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST AND
CHECK FOR FAULT CODES.
²IF THE POINTER MOVES DURING TEST BUT STILL
APPEARS ERRATIC, REPLACE CLUSTER ASSEMBLY.
TACHOMETER
INACCURATE.1. TACHOMETER OUT
OF CALIBRATION.1. PERFORM CLUSTER SELF-DIAGNOSTIC TEST.
²IF TACHOMETER IS ACCURATE TO THE CALIBRATION
POINTS, LOOK FOR ANOTHER POSSIBLE CAUSE OF
INACCURACY.
²IF TACHOMETER IS NOT ACCURATE TO THE
CALIBRATION POINTS, REPLACE CLUSTER ASSEMBLY.
FUEL GAUGE DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO POINTER
MOVEMENT.1. INTERNAL CLUSTER
FAILURE.1.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST.
²IF FUEL GAUGE POINTER MOVES TO
CALIBRATION POINTS, LOOK FOR ANOTHER
POSSIBLE CAUSE OF FAILURE.
²IF THE POINTER DOESN'T MOVE DURING TEST,
VERIFY POWER AND GROUND ARE BEING
PROVIDED TO THE CLUSTER. IF YES, REPLACE
CLUSTER ASSEMBLY. IF NO, DETERMINE CAUSE
OF NO POWER OR GROUND.
2. NO PCI FUEL
MESSAGE OR EMPTY
PCI BUS MESSAGE
FROM BODY
CONTROLLER.2.A. CHECK THE BCM USING A DRB IIITSCAN
TOOL. IF OK, GO TO STEP 2.B. IF NOT OK, REFER
TO THE PROPER BODY DIAGNOSTIC
PROCEDURES MANUAL TO PROPERLY DIAGNOSE
AND REPAIR.
2.B. REFER TO THE FUEL SECTION OF THE
SERVICE MANUAL FOR THE FUEL LEVEL SENDING
UNIT TEST PROCEDURE. TEST UNIT AND REPAIR
AS INSTRUCTED.
ERRATIC POINTER
MOVEMENT.1. BAD PCI FUEL
MESSAGE FROM THE
BODY CONTROLLER.1.A. USE A DRB IIITSCAN TOOL TO CHECK THE
BCM. IF OK, GO TO STEP 2.B. IF NOT OK, REFER
TO THE PROPER BODY DIAGNOSTIC
PROCEDURES MANUAL TO PROPERLY DIAGNOSE
AND REPAIR.
2.B. REFER TO THE FUEL SECTION OF THE
SERVICE MANUAL FOR THE FUEL LEVEL SENDING
UNIT TEST PROCEDURE. TEST UNIT. IF OK, LOOK
FOR ANOTHER POSSIBLE CAUSE FOR FUEL
GAUGE FAILURE. IF NOT OK, REPAIR SENDING
UNIT.
RSINSTRUMENT CLUSTER8J-7
INSTRUMENT CLUSTER (Continued)
ProCarManuals.com

CONDITION POSSIBLE CAUSES CORRECTION
2. INTERNAL CLUSTER
FAILURE.2. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK FOR FAULT CODES.
²IF THE POINTER MOVES DURING TEST BUT
STILL APPEARS ERRATIC, REPLACE CLUSTER
ASSEMBLY.
FUEL GAUGE
INACCURATE.1. FUEL GAUGE OUT OF
CALIBRATION.1. PERFORM CLUSTER SELF-DIAGNOSTIC TEST. IF
POINTER IS ACCURATE TO THE CALIBRATION
POINTS LOOK FOR ANOTHER POSSIBLE CAUSE
OF FAILURE. IF POINTER IS INACCURATE TO THE
CALIBRATION POINTS, REPLACE CLUSTER
ASSEMBLY.
2. FUEL LEVEL SENDING
UNIT IS OUT OF
CALIBRATION.2. REFER TO THE FUEL SECTION OF THE SERVICE
MANUAL FOR TESTING AND REPAIR PROCEDURE.
TEMPERATURE GAUGE DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO POINTER
MOVEMENT1. INTERNAL CLUSTER
FAILURE.1. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK.
²IF TEMPERATURE GAUGE POINTER MOVES TO
CALIBRATION POINTS, LOOK FOR ANOTHER
POSSIBLE CAUSE OF FAILURE.
²IF THE POINTER DOESN'T MOVE DURING TEST,
VERIFY POWER AND GROUND ARE BEING
PROVIDED TO THE CLUSTER. IF YES, REPLACE
CLUSTER. IF NO, DETERMINE CAUSE OF NO
POWER OR NO GROUND.
2. NO PCI
TEMPERATURE
MESSAGE OR COLD PCI
BUS MESSAGE FROM
THE POWERTRAIN
CONTROL MODULE.2.A. CHECK PCM FAULT CODES USING A DRB IIIT
SCAN TOOL. IF THERE ARE NO FAULTS, GO TO
STEP 2.B. IF THERE ARE FAULTS, REFER TO THE
PROPER ENGINE DIAGNOSTIC PROCEDURES
MANUAL TO PROPERLY DIAGNOSE AND REPAIR.
2.B. REFER TO FUEL, COOLANT TEMPERATURE
SENSOR, DIAGNOSIS AND TESTING. REPAIR
SENSOR AS NEEDED.
ERRATIC POINTER
MOVEMENT.1. BAD PCI BUS
MESSAGE FROM THE
POWERTRAIN CONTROL
MODULE.1.A. CHECK PCM FAULT CODES USING A DRB IIIT
SCAN TOOL. IF THERE ARE NO FAULTS, GO TO
STEP 1.B. IF THERE ARE FAULTS, REFER TO THE
ENGINE DIAGNOSTIC PROCEDURES MANUAL TO
PROPERLY DIAGNOSE AND REPAIR.
1.B. REFER TO FUEL, COOLANT TEMPERATURE
SENSOR, DIAGNOSIS AND TESTING. REPAIR
SENSOR AS NEEDED.
2. INTERNAL CLUSTER
FAILURE.2. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK FOR FAULT CODES.
²IF THE POINTER MOVES DURING TEST BUT
STILL APPEARS ERRATIC, REPLACE CLUSTER
ASSEMBLY.
8J - 8 INSTRUMENT CLUSTERRS
INSTRUMENT CLUSTER (Continued)
ProCarManuals.com

CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATURE GAUGE
INACCURATE.1. TEMPERATURE
GAUGE OUT OF
CALIBRATION.1. PERFORM CLUSTER SELF-DIAGNOSTIC TEST.
²IF POINTER IS ACCURATE TO THE CALIBRATION
POINTS LOOK FOR ANOTHER POSSIBLE CAUSE
OF FAILURE.
²IF POINTER IS INACCURATE TO THE
CALIBRATION POINTS, REPLACE CLUSTER
ASSEMBLY.
2. COOLANT SENSOR
OUT OF CALIBRATION.2. REFER TO FUEL, COOLANT TEMPERATURE
SENSOR FOR TEST AND REPAIR PROCEDURE.
ODOMETER DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO DISPLAY 1. NO PCI BUS
ODOMETER MESSAGE
FROM BCM.1. USE A DRB IIITSCAN TOOL TO CHECK THE
BCM. REFER TO THE PROPER BODY DIAGNOSTIC
PROCEDURES MANUAL TO PROPERLY DIAGNOSE
AND REPAIR.
2. INTERNAL CLUSTER
FAILURE.2. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK FOR FAULT CODES.
²IF ODOMETER PASSES THE SEGMENT CHECK,
LOOK FOR ANOTHER POSSIBLE CAUSE OF
FAILURE. IF IT FAILS VERIFY POWER AND
GROUND ARE BEING PROVIDED TO THE
CLUSTER. IF YES, REPLACE CLUSTER. IF NO,
DETERMINE CAUSE OF NO POWER OR GROUND.
ERRATIC DISPLAY 1. INTERNAL CLUSTER
FAILURE.1.A. PERFORM CLUSTER SELF-DIAGNOSTIC TEST
AND CHECK FOR FAULT CODES.
²IF ODOMETER PASSES THE SEGMENT TEST,
FAILURE MAY NOT BE IN THE CLUSTER. LOOK
FOR ANOTHER POSSIBLE CAUSE OF FAILURE.
VERIFY GOOD POWER AND GROUND
CONNECTIONS. IF CONNECTIONS ARE GOOD AND
NO OTHER PROBLEMS ARE FOUND, REPLACE
CLUSTER ASSEMBLY.
2. BAD PCI BUS
MESSAGE FROM THE
BCM.2. USE A DRB IIITSCAN TOOL TO CHECK THE
BCM. REFER TO THE PROPER BODY DIAGNOSTIC
PROCEDURES MANUAL TO PROPERLY DIAGNOSE
AND REPAIR.
ODOMETER WON'T GO
INTO TRIP MODE.1. TRIP SWITCH
DOESN'T WORK.1. IF CLUSTER WILL NOT GO INTO SELF
DIAGNOSTIC MODE AND CANNOT TOGGLE
BETWEEN ODOMETER AND TRIP ODOMETER,
REPLACE CLUSTER.
TRIP ODOMETER WON'T
RESET.1. RESET SWITCH
DOESN'T WORK.1. IF CLUSTER WILL NOT GO INTO SELF
DIAGNOSTIC MODE AND TRIP ODOMETER WILL
NOT RESET, REPLACE CLUSTER.
RSINSTRUMENT CLUSTER8J-9
INSTRUMENT CLUSTER (Continued)
ProCarManuals.com

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,
REFER TO THE PROPER TRANSMISSION
DIAGNOSTIC PROCEDURES MANUAL.
1.B. CHECK THE TCM USING A DRB IIITSCAN
TOOL. REFER TO THE PROPER TRANSMISSION
DIAGNOSTIC PROCEDURES MANUAL TO
PROPERLY DIAGNOSE AND REPAIR.
MECHANICAL TRANSMISSION RANGE INDICATOR (PRND21) DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
INDICATOR DOES NOT
SHOW PROPER GEAR
OR NO INDICATION.MIS-ADJUSTED 1.A. VERIFY TRANSMISSION SHIFT SYSTEM IS
CORRECTLY ADJUSTED.
1.B. VERIFY CORRECT ROUTING AND
ATTACHMENT OF PRNDL CABLE AND GUIDE TUBE.
1.C. RE-ADJUST PRNDL INDICATOR IN NEUTRAL
USING ADJUSTER WHEEL BELOW STEERING
COLUMN.
INDICATOR DOES NOT
FOLLOW GEAR SHIFT
LEVER.NOT ATTACHED 1.A. VERIFY INDICATOR CABLE CONNECTED TO
SHIFT LEVER PIN IN THE GROOVE.
1.B. VERIFY THAT THE INDICATOR CLIP IS SECURE,
AND ATTACHED TO THE MOUNTING BRACKET.
MAKE SURE THAT THE CLIP IS NOT BROKEN. IF
THE CLIP IS BROKEN, REPLACE CLIP ON
INDICATOR.
8J - 10 INSTRUMENT CLUSTERRS
INSTRUMENT CLUSTER (Continued)
ProCarManuals.com

LAMPS/LIGHTING - EXTERIOR
DESCRIPTION
LAMP SYSTEMS
RS vehicles use lighting on the interior and exte-
rior of the vehicle for illuminating and indicating
purposes. Lighting circuits are protected by fuses.
Lighting circuits require an overload protected power
source, on/off device, lamps and body ground to oper-
ate properly. Plastic lamps require a wire in the har-
ness to supply body ground to the lamp socket.
Replace sockets and bulbs that are corroded.
Some of the interior and exterior lighting functions
are governed by the Body Control Module. The head-
lamp, dome, and the door ajar switches provide sig-
nals to the Body Control Module. The Body Control
Module in turn sends a J1850 message to the Front
Control Module (FCM) to enable the necessary driv-
ers to set the required illumination configuration.
Wire connectors can make intermittent contact or
become corroded. Before coupling wire connectors,
inspect the terminals inside the connector. Male termi-
nals should not be bent or disengaged from the insu-
lator. Female terminals should not be sprung open or
disengaged from the insulator. Bent and sprung termi-
nals can be repaired using needle nose pliers and pick
tool. Corroded terminals appear chalky or green. Cor-
roded terminals should be replaced to avoid recur-
rence of the problem symptoms.
Begin electrical system failure diagnosis by testing
related fuses in the fuse block and intelligent power
module. Verify that bulbs are in good condition and
test continuity of the circuit ground. Refer to the
appropriate wiring information. The wiring informa-
tion includes wiring diagrams, proper wire and con-
nector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, splices and grounds.
AUTOMATIC HEADLAMP SYSTEM
The Automatic Headlamp system turns the instru-
mentation and exterior illumination lamps ON when
the ambient light levels are Night and OFF when
light levels are Day.
DAYTIME RUNNING LAMPS
Operating the high-beam headlamps at reduced
power provides daytime running lamps, which are
required on all new Canadian vehicles.
HEADLAMPS ON WITH WINDSHIELD WIPERS
For vehicles equipped with the Automatic Head-
lamp System, the instrumentation and exterior illu-
mination lamps will be turned ON when theheadlamp switch is in the AUTO position, RPM >
450 and the windshield wipers have been in the
intermittent, low or high mode of operation for more
than ten seconds. When the windshield wipers are
turned OFF the Body Control Module will determine
if the instrumentation and exterior illumination
lamps should remain ON base upon the current
ambient light level.
HEADLAMP SYSTEM
The configuration of the headlamp system of head-
lamps, park lamps and fog lamps is determined by
the BCM. The BCM determines the lighting configu-
ration as a result of the inputs from the ignition
switch, headlamp switch and multifunction switch. A
J1850 is transmitted from the BCM to the FCM to
enable the necessary drivers to set the illumination
configuration. Four wires are connected between the
headlamp switch and the BCM. The first wire con-
tains information regarding the position of the head-
lamp switch (Off, Automatic Headlamps, Automatic
Headlamp switch fog, Park with Fog, Head, or Head
with Fog Lamps). The second wire contains informa-
tion regarding the position of the dimmer switch
(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 J1850 message
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.
8L - 2 LAMPS/LIGHTING - EXTERIORRS
ProCarManuals.com

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 Front Control Module (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. The system will return to normal oper-
ation 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 J1850 to the
FCM informing the FCM to turn off the headlamps,
park lamps and fog lamps. This feature prevents the
vehicle battery from being discharged when the vehi-
cle 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.
LAMP OUTAGE
If one or more of the following lamps (Low and/or
High beams) are out, then a ªlamps outº indicator
located in the cluster will illuminate.
OPTICAL HORN/HIGH BEAMS
When the multifunction switch is pulled to the first
detent (optical horn) signal, the headlamps are ON,
key-in the ignition the BCM shall send a message via
J1850 to the FCM to turn on the headlamps drivers
to illuminate all four filaments (Low and High
beams). When the multifunction switch is pulled to
the second detent (high beam) signal and the head-
lamps are ON, the BCM shall send a message via
J1850 to the FCM to turn on the headlamps drivers.
The High Beams are illuminated and the Low Beams
and Fog Lamps (if ON) are extinguished. If the head-
lamps were in the high beam configuration when
power was removed from the headlamps, the head-
lamps will be configured as low beam the next time
they are activated.
DIAGNOSIS AND TESTING
WARNING: EYE PROTECTION SHOULD BE USED
WHEN SERVICING GLASS COMPONENTS. PER-
SONAL INJURY CAN RESULT.
CAUTION: Do not touch the glass of halogen bulbs
with fingers or other possibly oily surface, reduced
bulb life will result. Do not use bulbs other than
those indicated in the Bulb Application table. Dam-
age to lamp and/or Daytime Running Lamp Module
can result. Do not use fuses, circuit breakers or
relays having greater amperage value than indi-
cated on the fuse panel or in the Owners Manual.
When a vehicle experiences problems with the
headlamp system, verify the condition of the battery
connections, fuses, charging system, headlamp bulbs,
wire connectors, relay, high beam switch, dimmer
switch, and headlamp switch. Refer to the appropri-
ate 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 connec-
tors, splices and grounds.
Each vehicle is equipped with various lamp assem-
blies. A good ground is necessary for proper lighting
operation. Grounding is provided by the lamp socket
when it comes in contact with the metal body, or
through a separate ground wire.
When changing lamp bulbs check the socket for
corrosion. If corrosion is present, clean it with a wire
brush.
When it is necessary to remove components to ser-
vice another, it should not be necessary to apply
excessive force or bend a component to remove it.
Before damaging a trim component, verify hidden
fasteners or captured edges are not holding the com-
ponent in place.
RSLAMPS/LIGHTING - EXTERIOR8L-3
LAMPS/LIGHTING - EXTERIOR (Continued)
ProCarManuals.com

HEADLAMPS
CONDITION POSSIBLE CAUSES CORRECTION
HEADLAMPS ARE DIM
WITH ENGINE IDLING1. Loose or corroded battery cables. 1. Clean and secure battery cable clamps
and posts.
OR IGNITION TURNED
OFF2. Loose or worn generator drive belt. 2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system, refer
to Electrical, Charging
4. Battery has insufficient charge. 4. Test battery state-of -charge, refer to
Electrical, Battery System.
5. Battery is sulfated or shorted. 5. Load test battery, refer to Electrical,
Battery System.
6. Poor lighting circuit Z343/Z344-
ground.6. Test for voltage drop across Z343/Z344-
ground locations, refer to Electrical, Wiring
Diagram Information.
HEADLAMP BULBS BURN
OUT FREQUENTLY1. Intelligent Power Module (IPM) not
controlling voltage.1. Test and repair Intelligent Power
Module.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and
splices. Refer to Electrical, Wiring
Information.
HEADLAMPS ARE DIM
WITH ENGINE RUNNING
ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system, refer
to Electrical, Wiring Information.
2. Poor lighting circuit Z343/Z344-
ground.2. Test for voltage drop across Z343/Z344-
ground locations, refer to Electrical, Wiring
Information.
3. High resistance in headlamp
circuit.3. Test amperage draw of headlamp
circuit.
HEADLAMPS FLASH
RANDOMLY1. Poor lighting circuit Z343/Z344-
ground.1. Test for voltage drop across Z343/Z344-
ground locations, refer to Electrical, Wiring
Information.
2. Variable resistance in headlamp
circuit.2. Test amperage draw of headlamp
circuit.
3. Loose or corroded terminals or
splices in circuit.3. Inspect and repair all connectors and
splices, refer to Electrical, Wiring
Information.
4. Faulty headlamp switch. 4. Replace headlamp switch.
HEADLAMPS DO NOT
ILLUMINATE1. No voltage to headlamps. 1. Repair open headlamp circuit, refer to
Electrical, Wiring Information.
2. No Z343/Z344-ground at
headlamps.2. Repair circuit ground, refer to Electrical,
Wiring Information.
3. Broken connector terminal or wire
splice in headlamp circuit.3. Repair connector terminal or wire splice.
4. Faulty or burned out bulb. 4. Replace headlamp bulb(s).
5. Body Control Module malfunction. 5. Refer to appropriate Body Control
Module diagnostics.
8L - 4 LAMPS/LIGHTING - EXTERIORRS
LAMPS/LIGHTING - EXTERIOR (Continued)
ProCarManuals.com

CONDITION POSSIBLE CAUSES CORRECTION
6. J1850 Bus Communication 6. Verify messages being transmitted by
BCM and received by FCM.
7. IPM/FCM Malfunction. 7. Refer to appropriate IPM/FCM
diagnostics.
HEADLAMPS ON WITH
IGNITION IN RUN, WITH
HEADLAMP SWITCH OFF1. Faulty headlamp switch. 1. Replace headlamp switch (review BCM
logged faults).
2. Diagnostic tool indicates (4.7 -
5.0V) on headlamp switch input to
BCM.2. Inspect and repair terminals, connectors
and open circuits.
3. J1850 Bus Communication. 3. Verify messages being transmitted by
BCM and received by FCM.
FOG LAMPS
CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM
WITH ENGINE IDLING
OR IGNITION TURNED
OFF.1. Loose or corroded battery cables. 1. Clean and secure battery cable clamps
and posts.
2. Loose or worn generator drive belt. 2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system. Refer to
Electrical, Charging,
4. Battery has insufficient charge. 4. Test battery state-of -charge. Refer to
Electrical, Battery System.
5. Battery is sulfated or shorted. 5. Load test battery. Refer to Electrical,
Battery System.
6. Poor lighting circuit Z349/Z248
ground.6. Test for voltage drop across Z349/248
ground locations. Refer to Electrical, Wiring
Information.
FOG LAMP BULBS BURN
OUT FREQUENTLY1. Charging system output too high. 1. Test and repair charging system. Refer to
Electrical, Charging.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and
splices. Refer to Electrical, Wiring
Information.
FOG LAMPS ARE DIM
WITH ENGINE RUNNING
ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system. Refer to
Electrical, Charging.
2. Poor lighting circuit Z349/Z248
ground.2. Test for voltage drop across Z349/Z248
ground locations. Refer to Electrical, Wiring
Information.
3. High resistance in fog lamp circuit. 3. Test amperage draw of fog lamp circuit.
FOG LAMPS FLASH
RANDOMLY1. Poor lighting circuit Z349/Z248
ground.1. Test for voltage drop across Z349/Z248
ground locations. Refer to Electrical, Wiring
Information.
2. Variable resistance in fog lamp
circuit.2. Test amperage draw of fog lamp circuit.
RSLAMPS/LIGHTING - EXTERIOR8L-5
LAMPS/LIGHTING - EXTERIOR (Continued)
ProCarManuals.com