Short to ground JEEP GRAND CHEROKEE 2003 WJ / 2.G Owner's Guide

FUEL GAUGE
DESCRIPTION
A fuel gauge is standard equipment on all instru-
ment clusters. The fuel gauge is located in the lower
left corner of the instrument cluster, to the left of the
tachometer. The fuel gauge consists of a movable
gauge needle or pointer controlled by the instrument
cluster circuitry and a fixed 90 degree scale on the
gauge dial face that reads left-to-right from E (or
Empty) to F (or Full). An International Control and
Display Symbol icon for ªFuelº is located on the
gauge dial face. An arrowhead pointed to the left side
of the vehicle is imprinted next to the ªFuelº icon on
the fuel gauge dial face to provide the driver with a
reminder as to the location of the fuel filler access.
The fuel gauge graphics are either white, gray and
orange against a black gauge dial face (base cluster)
or black and gray against a taupe gauge dial face
(premium cluster), making them clearly visible
within the instrument cluster in daylight. When illu-
minated from behind by the panel lamps dimmer
controlled cluster illumination lighting with the exte-
rior lamps turned On, the base cluster white gauge
graphics appear blue-green and the orange graphics
still appear orange, while the premium cluster taupe
gauge dial face appears blue-green with the black
graphics silhouetted against the illuminated back-
ground. The gray gauge graphics for both versions of
the cluster are not illuminated. The orange gauge
needle in the base cluster gauge is internally illumi-
nated, while the black gauge needle in the premium
cluster gauge is not.
Base cluster gauge illumination is provided by
replaceable incandescent bulb and bulb holder units
located on the instrument cluster electronic circuit
board. Premium cluster gauge illumination is pro-
vided by an integral electro-luminescent lamp that is
serviced as a unit with the instrument cluster. The
fuel gauge is serviced as a unit with the instrument
cluster.
OPERATION
The fuel gauge gives an indication to the vehicle
operator of the level of fuel in the fuel tank. This
gauge is controlled by the instrument cluster circuit
board based upon cluster programming and elec-
tronic messages received by the cluster from the
Powertrain Control Module (PCM) over the Program-
mable Communications Interface (PCI) data bus. The
fuel gauge is an air core magnetic unit that receives
battery current on the instrument cluster electronic
circuit board through the fused ignition switch out-
put (run-start) circuit whenever the ignition switch is
in the On or Start positions. The cluster is pro-
grammed to move the gauge needle back to the lowend of the scale after the ignition switch is turned to
the Off position. The instrument cluster circuitry
controls the gauge needle position and provides the
following features:
²Percent Tank Full Message- Each time the
cluster receives a message from the PCM indicating
the percent tank full, the cluster moves the gauge
needle to the relative fuel level position on the gauge
scale. The PCM applies an algorithm to the input
from the fuel tank sender to dampen gauge needle
movement against the negative effect that fuel slosh-
ing within the fuel tank can have on accurate inputs
to the PCM.
²Less Than 12.5 Percent Tank Full Message-
Each time the cluster receives messages from the
PCM indicating the percent tank full is less than
12.5 (one-eighth), the gauge needle is moved to the
proper position on the gauge scale and the low fuel
indicator is illuminated. The low fuel indicator
remains illuminated until the cluster receives mes-
sages from the PCM indicating that the percent tank
full is greater than 12.5 (one-eighth), or until the
ignition switch is turned to the Off position, which-
ever occurs first.
²Less Than Empty Percent Tank Full Mes-
sage- Each time the cluster receives a message from
the PCM indicating the percent tank full is less than
empty, the gauge needle is moved to the far left (low)
end of the gauge scale and the low fuel indicator is
illuminated immediately. This message would indi-
cate that the fuel tank sender input to the PCM is a
short circuit.
²More Than Full Percent Tank Full Message
- Each time the cluster receives a message from the
PCM indicating the percent tank full is more than
full, the gauge needle is moved to the far left (low)
end of the gauge scale and the low fuel indicator is
illuminated immediately. This message would indi-
cate that the fuel tank sender input to the PCM is an
open circuit.
²Communication Error- If the cluster fails to
receive a percent tank full message, it will hold the
gauge needle at the last indication for about twelve
seconds, until a new message is received, or until the
ignition switch is turned to the Off position, which-
ever occurs first. After twelve seconds, the cluster
will return the gauge needle to the low end of the
gauge scale.
²Actuator Test- Each time the cluster is put
through the actuator test, the gauge needle will be
swept across the entire gauge scale and back in order
to confirm the functionality of the gauge and the
cluster control circuitry.
The PCM continually monitors the fuel tank
sender to determine the fuel level. The PCM then
applies an algorithm to the input and sends the
WJINSTRUMENT CLUSTER 8J - 21

tor lens is serviced as a unit with the instrument clus-
ter lens, hood and mask unit.
OPERATION
The low fuel indicator gives an indication to the
vehicle operator when the level of fuel in the fuel
tank becomes low. This indicator is controlled by a
transistor on the instrument cluster electronic circuit
board based upon cluster programming and elec-
tronic messages received by the cluster from the
Powertrain Control Module (PCM) over the Program-
mable Communications Interface (PCI) data bus. The
low fuel indicator bulb is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster receives a battery current input on the
fused ignition switch output (run-start) circuit.
Therefore, the indicator will always be off when the
ignition switch is in any position except On or Start.
The bulb only illuminates when it is switched to
ground by the instrument cluster transistor. The
instrument cluster will turn on the low fuel indicator
for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the low fuel indicator is
illuminated for about three seconds as a bulb test.
²Less Than 12.5 Percent Tank Full Message-
Each time the cluster receives a message from the
PCM indicating that the percent tank full is less
than about 12.5 (one-eighth), the low fuel indicator is
illuminated. The indicator remains illuminated until
the cluster receives messages from the PCM indicat-
ing that the percent tank full has increased to
greater than about 12.5 (one-eighth). The PCM
applies an algorithm to the input from the fuel tank
sender to dampen the illumination of the low fuel
indicator against the negative effect that fuel slosh-
ing within the fuel tank can have on accurate inputs
to the PCM.
²Less Than Empty Percent Tank Full Mes-
sage- Each time the cluster receives a message from
the PCM indicating the percent tank full is less than
empty, the low fuel indicator is illuminated immedi-
ately. This message would indicate that the fuel tank
sender input to the PCM is a short circuit.
²More Than Full Percent Tank Full Message
- Each time the cluster receives a message from the
PCM indicating the percent tank full is more than
full, the low fuel indicator is illuminated immedi-
ately. This message would indicate that the fuel tank
sender input to the PCM is an open circuit.
²Communication Error- If the cluster fails to
receive a percent tank full message for more than
about twelve seconds, the cluster control circuitry
will illuminate the low fuel indicator until a new per-
cent tank full message is received.²Actuator Test- Each time the cluster is put
through the actuator test, the low fuel indicator will
be turned on for the duration of the test to confirm
the functionality of the bulb and the cluster control
circuitry.
The PCM continually monitors the fuel tank
sender input to determine the fuel level. The PCM
then applies an algorithm to the input and sends the
proper percent tank full messages to the instrument
cluster. If the low fuel indicator fails to light during
the bulb test, replace the bulb with a known good
unit. For further diagnosis of the low fuel indicator
or the instrument cluster circuitry that controls the
indicator, (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). For
proper diagnosis of the fuel tank sender, the PCM,
the PCI data bus, or the electronic message inputs to
the instrument cluster that control the low fuel indi-
cator, a DRBIIItscan tool is required. Refer to the
appropriate diagnostic information.
MALFUNCTION INDICATOR
LAMP (MIL)
DESCRIPTION
A Malfunction Indicator Lamp (MIL) is standard
equipment on all instrument clusters. The MIL is
located near the right edge of the instrument cluster,
to the right of the speedometer. The MIL consists of
an International Control and Display Symbol icon for
ªEngineº imprinted on an amber lens. The lens is
located behind a cutout in the opaque layer of the
instrument cluster overlay. The dark outer layer of
the overlay prevents the icon from being clearly vis-
ible when the indicator is not illuminated. The icon
appears silhouetted against an amber field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by a replaceable
incandescent bulb and bulb holder unit located on
the instrument cluster electronic circuit board. The
MIL lens is serviced as a unit with the instrument
cluster lens, hood and mask unit.
OPERATION
The Malfunction Indicator Lamp (MIL) gives an
indication to the vehicle operator when the Power-
train Control Module (PCM) has recorded a Diagnos-
tic Trouble Code (DTC) for an On-Board Diagnostics
II (OBDII) emissions-related circuit or component
malfunction. This indicator is controlled by a transis-
tor on the instrument cluster electronic circuit board
based upon cluster programming and electronic mes-
sages received by the cluster from the PCM over the
Programmable Communications Interface (PCI) data
bus. The MIL bulb is completely controlled by the
WJINSTRUMENT CLUSTER 8J - 23
LOW FUEL INDICATOR (Continued)

ergize the combination flasher in response to mes-
sage inputs received over the Programmable
Communications Interface (PCI) data bus network.
The BCM can energize the combination flasher when
the VTSS is requested.
Vehicles equipped with the optional Electronic
Vehicle Information Center (EVIC) use turn signal
status messages received from the Electro-Mechani-
cal Instrument Cluster (EMIC) and distance mes-
sages received from the Powertrain Control Module
(PCM) over the PCI data bus to determine when the
Turn Signal On warning should be activated. The
EMIC receives hard wired inputs from the combina-
tion flasher to operate the turn signal indicators,
then sends the proper turn signal status message to
the EVIC. If a turn signal is left on for more than
about 1.6 kilometers (1 mile) of driving distance, the
EVIC will display a visual ªTurn Signal Onº message
and will send a request to the BCM over the PCI
data bus to notify the vehicle operator.
During both the turn signal and the hazard warn-
ing operation, if the exterior lamps are turned Off,
the front park/turn signal lamps and the front side
marker lamps will flash in unison. If the exterior
lamps are turned On, the front park/turn signal
lamps and the front side marker lamps will flash
alternately. Refer to the owner's manual.
DIAGNOSIS AND TESTING - TURN SIGNAL &
HAZARD WARNING SYSTEMS
When diagnosing the turn signal and hazard warn-
ing circuits, remember that high generator output
can burn out bulbs rapidly and repeatedly. If this is a
concern on the vehicle being diagnosed, test the
charging system as required.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Turn the ignition switch to the On position.
Actuate the turn signal switch or the hazard warning
switch. Observe the turn signal indicator lamp(s) in
the instrument cluster. If the flash rate is very high,
check for a turn signal bulb that is not lit or is verydimly lit. Repair the circuits to that lamp or replace
the faulty bulb, as required. If the turn signal indi-
cator(s) fail to light, go to Step 2.
(2) Turn the ignition switch to the Off position.
Check the ignition run fuse and the flasher fuse in
the Junction Block (JB). If OK, go to Step 3. If not
OK, repair the shorted circuit or component as
required and replace the faulty fuse(s).
(3) Check for battery voltage at the flasher fuse in
the JB. If OK, go to Step 4. If not OK, repair the
open fused B(+) circuit between the JB and the
Power Distribution Center (PDC).
(4) Turn the ignition switch to the On position.
Check for battery voltage at the ignition run fuse in
the JB. If OK, go to Step 5. If not OK, repair the
open fused ignition switch output (run) circuit
between the JB and the ignition switch.
(5) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the combination flasher from the JB and
replace it with a known good unit. Reconnect the bat-
tery negative cable. Test the operation of the turn
signal and hazard warning systems. If OK, discard
the faulty combination flasher. If not OK, remove the
test flasher and go to Step 6.
(6) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run) circuit cavity in the JB for the combina-
tion flasher. If OK, go to Step 7. If not OK, repair the
open fused ignition switch output (run) circuit
between the combination flasher and the ignition run
fuse in the JB.
(7) Turn the ignition switch to the Off position.
Check for battery voltage at the B(+) circuit of the JB
for the combination flasher. If OK, go to Step 8. If
not OK, repair the open B(+) circuit between the
combination flasher and the flasher fuse in the JB.
(8) Disconnect and isolate the battery negative
cable. Disconnect the instrument panel wire harness
connector for the turn signal and hazard warning
switches from the multi-function switch connector.
Check for continuity between the ground circuit of
the instrument panel wire harness connector for the
left multi-function switch and a good ground. There
should be continuity. If OK, go to Step 9. If not OK,
repair the open ground circuit.
(9) Check for continuity between the hazard switch
sense circuit of the instrument panel wire harness
connector for the multi-function switch and a good
ground. There should be no continuity. If OK, go to
Step 10. If not OK, repair the shorted hazard switch
sense circuit between the multi-function switch and
the combination flasher.
(10) Check for continuity between the hazard
switch sense circuit of the JB for the combination
flasher and the instrument panel wire harness con-
WJLAMPS/LIGHTING - EXTERIOR 8L - 3
LAMPS/LIGHTING - EXTERIOR (Continued)

nector for the multi-function switch. There should be
continuity. If OK, go to Step 11. If not OK, repair the
open hazard switch sense circuit between the multi-
function switch and the combination flasher.
(11) Check for continuity between the turn switch
sense circuit of the instrument panel wire harness
connector for the multi-function switch and a good
ground. There should be no continuity. If OK, go to
Step 12. If not OK, repair the shorted left turn
switch sense circuit between the multi-function
switch and the combination flasher.
(12) Check for continuity between the left turn
switch sense circuit of the JB for the combination
flasher and the instrument panel wire harness con-
nector for the multi-function switch. There should be
continuity. If OK, go to Step 13. If not OK, repair the
open left turn switch sense circuit between the multi-
function switch and the combination flasher.
(13) Check for continuity between the right turn
switch sense circuit of the instrument panel wire
harness connector for the left multi-function switch
and a good ground. There should be no continuity. If
OK, go to Step 14. If not OK, repair the shorted right
turn switch sense circuit between the left multi-func-
tion switch and the combination flasher.
(14) Check for continuity between the right turn
switch sense circuit of the JB for the combination
flasher and the instrument panel wire harness con-
nector for the multi-function switch. There should be
continuity. If OK, test the left multi-function switch.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/LEFT MULTI-FUNCTION SWITCH -
DIAGNOSIS AND TESTING). If not OK, repair the
open right turn switch sense circuit between the
multi-function switch and the combination flasher as
required.
SPECIFICATIONS
EXTERIOR LAMPS
CAUTION: Do not use bulbs other than the bulbs
listed in the Bulb Application Table. Damage to
lamp can result. Do not touch halogen bulbs with
fingers or other oily surfaces. Bulb life will be
reduced.
LAMP BULB TYPE
BACK-UP 3157
CENTER HIGH
MOUNTED STOP LAMP921
FOG LAMP 9005
FRONT SIDE MARKER 194/194NA
LAMP BULB TYPE
FRONT TURN SIGNAL 3157/3157NA
HIGH BEAM 9005XS
LOW BEAM 9006XS
LICENSE PLATE 168
TAIL/BRAKE 3157
REAR TURN SIGNAL 3157
UNDERHOOD LAMP 561
AUTO HEADLAMP SENSOR
DIAGNOSIS AND TESTING - AUTO HEADLAMP
SENSOR (AHL)
The auto headlamp sensor needs real sunlight to
properly register the light level. When auto head-
lamps are enabled indoors, the headlamps may be
turned on. The sensor is located in the center of the
defroster grille at the base of the windshield. There
are no faults set in the Body Control Module (BCM)
for a inoperative or missing AHL Sensor. Symptom of
a missing sensor or unconnected sensor would be
that the Headlamps and Parklamps turn on when
the vehicle is started and there is a high level of
ambient light present (ie. daytime). Auto headlamps
should not function in the presence of daylight.
REMOVAL
(1) Remove the instrument panel top cover. (Refer
to 23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - REMOVAL) for service proce-
dures.
(2) Remove the screw attaching auto headlamp
sensor to instrument panel (Fig. 1).
(3) Disengage the harness connector from auto
headlamp sensor.
(4) Separate the auto headlamp sensor from
instrument panel.
INSTALLATION
(1) Position the auto headlamp sensor on instru-
ment panel.
(2) Engage the harness connector to auto head-
lamp sensor.
(3) Install the screw attaching auto headlamp sen-
sor to instrument panel.
(4) Install the instrument panel top cover. (Refer
to 23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - INSTALLATION) for service
procedures.
8L - 4 LAMPS/LIGHTING - EXTERIORWJ
LAMPS/LIGHTING - EXTERIOR (Continued)

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING Ð HEADLAMP
SYSTEM
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 Z1-ground. 6. Test for voltage drop across Z1-ground
locations, refer to Electrical, Wiring Digram
Information.
7. Both headlamp bulbs defective. 7. Replace both headlamp bulbs.
HEADLAMP BULBS BURN
OUT1. Charging system output too high. 1. Test and repair charging system, refer
to Electrical, Charging.
FREQUENTLY 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 RUNNING1. Charging system output too low. 1. Test and repair charging system, refer
to Electrical, Wiring Information.
ABOVE IDLE* 2. Poor lighting circuit Z1-ground. 2. Test for voltage drop across Z1-ground
locations, refer to Electrical, Wiring
Information.
3. High resistance in headlamp
circuit.3. Test amperage draw of headlamp
circuit.
4. Both headlamp bulbs defective. 4. Replace both headlamp bulbs.
HEADLAMPS FLASH
RANDOMLY1. Poor lighting circuit Z1-ground. 1. Test for voltage drop across Z1-ground
locations, refer to Electrical, Wiring
Information.
2. High resistance in headlamp
circuit.2. Test amperage draw of headlamp
circuit. Should not exceed 30 amps.
3. Loose or corroded terminals or
splices in circuit.3. Inspect and repair all connectors and
splices, refer to Electrical, Wiring
Information.
HEADLAMPS DO NOT
ILLUMINATE1. No voltage to headlamps. 1. Repair open headlamp circuit, refer to
Electrical, Wiring Information.
2. No Z1-ground at headlamps. 2. Repair circuit ground, refer to Electrical,
Wiring Information.
8L - 12 LAMPS/LIGHTING - EXTERIORWJ
HEADLAMP (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
3. Faulty headlamp switch. 3. Refer to BCM diagnostics.
4. Blown fuse for headlamps. 4. Replace fuse refer to Electrical, Wiring
Information.
5. Broken connector terminal or wire
splice in headlamp circuit.5. Repair connector terminal or wire splice.
6. Both headlamp bulbs defective. 6. Replace both headlamp bulbs.
*Canada vehicles must have lamps ON.
FOG LAMP
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 Z1-ground. 6. Test for voltage drop across Z1-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 Z1-ground. 2. Test for voltage drop across Z1-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 Z1-ground. 1. Test for voltage drop across Z1-ground
locations. Refer to Electrical, Wiring
Information.
2. High resistance in fog lamp circuit. 2. Test amperage draw of fog lamp circuit.
3. Faulty multifunction switch. 3. Refer to Electrical, Electronic Control
Modules.
4. Loose or corroded terminals or
splices in circuit.4. Inspect and repair all connectors and
splices. Refer to Electrical, Wiring
Information.
WJLAMPS/LIGHTING - EXTERIOR 8L - 13
HEADLAMP (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS DO NOT
ILLUMINATE1. Blown fuse for fog lamp. 1. Replace fuse. Refer to Electrical, Wiring
Information.
2. No Z1-ground at fog lamps. 2. Repair circuit ground. Refer to Electrical,
Wiring Information.
3. Faulty multifunction switch. 3. Refer to Electrical, Wiring Information.
4. Broken connector terminal or wire
splice in fog lamp circuit.4. Repair connector terminal or wire splice.
5. Defective or burned out bulb. 5. Replace bulb.
DAYTIME RUNNING LAMP
CONDITION POSSIBLE CAUSES CORRECTION
DAYTIME RUNNING LAMPS DO
NOT WORK1. Poor connection at DRL module. 1. Secure connector on DRL
module.
2. Parking brake engaged. 2. Disengage parking brake.
3. Parking brake circuit shorted to
ground.3. Check cluster telltale, refer to
Group 8W.
4. Headlamp circuit shorted to
ground.4. Refer to Group 8W.
5. Defective DRL relay. 5. Replace DRL relay.
6. Body controller not programed
with Canadian country code.6. Check country code.
7. DRL relay is missing. 7. Install DRL relay.
8. Blown fuse for DRL. 8. Replace fuse refer to Electrical,
Wiring Information.
Clicking or chattering when DRL is
on.1. Mechanical relay is installed in
the junction block.1. Ensure that the DRL relay is
installed in the proper socket in
junction block, and that no
mechanical relay exists in the low
beam socket.
DIAGNOSIS AND TESTING Ð HEADLAMP
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.
Each vehicle is equipped with various lamp assem-
blies. A good power feed and ground are necessary forproper 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 and coat the inside of the socket lightly with
Mopar Multi-Purpose Grease or equivalent.
REMOVAL - BULB
(1) Remove the headlamp.
(2) Turn the bulb socket one quarter turn counter
clockwise.
(3) Remove the socket from lamp (Fig. 13).
(4) Remove the bulb from socket.
8L - 14 LAMPS/LIGHTING - EXTERIORWJ
HEADLAMP (Continued)

INSTALLATION - BULB
CAUTION: Do not touch the bulb glass with fingers
or other oily surfaces. Reduced bulb life will result.
(1) Position the bulb into socket and push into
place.
(2) Position the bulb socket in headlamp and turn
the bulb socket one quarter turn clockwise.
(3) Install the headlamp.
HEADLAMP SWITCH
DESCRIPTION
The headlamp switch is part of the left multi-func-
tion switch. A knob on the end of the multi-function
switch control stalk controls all of the exterior light-
ing switch functions. The exterior lighting switch is
hard wired to the Body Control Module (BCM).
The exterior lighting switch cannot be adjusted or
repaired and, if faulty or damaged, the entire left
multi-function switch unit must be replaced. (Refer
to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTERI-
OR/TURN SIGNAL/HAZARD SWITCH - REMOVAL)
for the service procedures. (Refer to 8 - ELECTRI-
CAL/ELECTRONIC CONTROL MODULES/BODY
CONTROL/CENTRAL TIMER MODUL - DESCRIP-
TION) for more information on this component.
OPERATION
The exterior lighting switch uses a hard wired five
volt reference circuit from the BCM, resistor multi-
plexing and a hard wired switch output circuit to
provide the BCM with a zero to five volt signal thatindicates the status of all of the exterior lighting
switch settings. The BCM then uses control outputs
to energize the headlamp and park lamp relays that
activate the exterior lighting circuits.
The BCM monitors the exterior lighting switch sta-
tus, then sends the proper switch status messages to
other modules over the Programmable Communica-
tions Interface (PCI) data bus network. The exterior
lighting switch status is also used by the BCM as an
input for chime warning system operation.
DIAGNOSIS AND TESTING Ð HEADLAMP
SWITCH
Before testing the headlamp switch, turn on the
exterior lighting and open the driver side front door.
If the exterior lamps of the vehicle operate, but there
is no chime warning issued with the driver side front
door open, (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - INTERIOR/DOOR AJAR SWITCH -
DIAGNOSIS AND TESTING). If the exterior lamps
of the vehicle are inoperative, but the chime warning
is issued, (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR - DIAGNOSIS AND TESTING).
If the exterior lamps and the chime warning are
both inoperative, test the left multi-function switch.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR - DIAGNOSIS AND TESTING). If the
multi-function switch tests OK, proceed as follows.
The following tests will help to locate a short or open
in the hard wired circuits between the multi-function
switch and the Body Control Module (BCM). For
complete circuit diagrams, refer to the appropriate
wiring information.
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.
(1) Disconnect and isolate the battery negative
cable. Disconnect the instrument panel wire harness
connector from the left multi-function switch connec-
tor. Disconnect the instrument panel wire harness
connector from the Body Control Module (BCM).
Check for continuity between the headlamp switch
mux circuit of the instrument panel wire harness
connector for the multi-function switch and a good
ground. There should be no continuity. If OK, go to
Step 2. If not OK, repair the shorted headlamp
switch mux circuit.
(2) Check for continuity between the headlamp
switch mux circuit of the instrument panel wire har-
Fig. 13 Headlamp Bulb
1 - HIGH BEAM BULB
2 - LOW BEAM BULB
3 - MARKER BULB
4 - PARK/TURN SIGNAL BULB
WJLAMPS/LIGHTING - EXTERIOR 8L - 15
HEADLAMP (Continued)

ness connector for the multi-function switch and the
instrument panel wire harness connector for the
BCM. There should be continuity. If OK, go to Step 3.
If not OK, repair the open headlamp switch mux cir-
cuit.
(3) Check for continuity between the headlamp
switch return circuit of the instrument panel wire
harness connector for the multi-function switch and a
good ground. There should be no continuity. If OK, go
to Step 4. If not OK, repair the shorted headlamp
switch return circuit.
(4) Check for continuity between the headlamp
switch return circuit of the instrument panel wire
harness connector for the multi-function switch and
the instrument panel wire harness connector for the
BCM. There should be continuity. If OK, use a
DRBIIItscan tool and the proper Diagnostic Proce-
dures manual to test the BCM. If not OK, repair the
open headlamp switch return circuit.
HEADLAMP UNIT
REMOVAL
(1) Remove the jack screw attaching the top of
headlamp to the headlamp mounting module (Fig.
14).
(2) Grasp upper inboard and lower outboard cor-
ners of headlamp (Fig. 15) and pull headlamp out-
ward.
(3) Remove all of the bulb sockets from headlamp
module.
(4) Separate the headlamp from vehicle.
INSTALLATION
CAUTION: Do not touch the bulb glass with fingers
or other oily surfaces. Reduced bulb life will result.
(1) Install all of the bulb sockets in headlamp mod-
ule.
(2) Position the headlamp on the vehicle and align
the ball studs with the sockets.
(3) Push the headlamp inward to secure the ball
studs with the sockets.
(4) Install the jack screw attaching the top of
headlamp to the headlamp mounting module.
ADJUSTMENTS
VEHICLE PREPARATION FOR LAMP ALIGNMENT
(1) Verify headlamp dimmer switch and high beam
indicator operation.
(2) Correct defective components that could hinder
proper lamp alignment.
(3) Verify proper tire inflation.
(4) Clean lamp lenses.
(5) Verify that luggage area is not heavily loaded.
(6) Fuel tank should be FULL. Add 2.94 kg (6.5
lbs.) of weight over the fuel tank for each estimated
gallon of missing fuel.
LAMP ALIGNMENT SCREEN PREPARATION
(1) Position vehicle on a level surface perpendicu-
lar to a flat wall 7.62 meters (25 ft) away from front
of headlamp lens (Fig. 16).
(2) If necessary, tape a line on the floor 7.62
meters (25 ft) away from and parallel to the wall.
(3) Measure from the floor up 1.27 meters (5 ft)
and tape a line on the wall at the centerline of the
vehicle. Sight along the centerline of the vehicle
Fig. 14 Headlamp Jackscrew
1 - JACKSCREW
2 - HEADLAMP
Fig. 15 Headlamp Removal
1 - HEADLAMP
8L - 16 LAMPS/LIGHTING - EXTERIORWJ
HEADLAMP SWITCH (Continued)

(3) Disconnect the door wire harness connector
from the Driver Door Module (DDM) connector.
Check for continuity between the driver door ajar
switch sense circuit of the door wire harness connec-
tor for the DDM and a good ground. There should be
no continuity. If OK, go to Step 4. If not OK, repair
the shorted driver door ajar switch sense circuit.
(4) Check for continuity between the driver door
ajar switch sense circuit of the door wire harness
connector for the DDM and the 4-way door wire har-
ness connector for the front door latch. There should
be continuity. If OK, go to Step 5. If not OK, repair
the open driver door ajar switch sense circuit.
(5) Check for continuity between the ground cir-
cuit terminal and the driver door ajar switch sense
circuit terminal of the front door latch connector.
There should be continuity with the driver side front
door open, and no continuity with the door closed. If
OK, use a DRBIIItscan tool and the proper Diagnos-
tic Procedures manual to test the operation of the
PCI data bus and the DDM. If not OK, replace the
faulty driver side front door latch unit.
GLOVE BOX LAMP/SWITCH
REMOVAL
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.
(1) Disconnect and isolate the battery negative
cable.
(2) Roll down the glove box from the instrument
panel.(Refer to 23 - BODY/INSTRUMENT PANEL/
GLOVE BOX - REMOVAL) for the procedures.
(3) Remove the lower right center bezel from the
instrument panel.(Refer to 23 - BODY/INSTRU-
MENT PANEL - REMOVAL) for the procedures.
(4) Reach through the glove box opening and
depress the retaining latches on the top and bottom
of the glove box lamp and switch housing.
(5) While holding the retaining latches depressed,
push the glove box lamp and switch out through the
mounting hole (Fig. 1).
(6) Disconnect the instrument panel wire harness
connector from the glove box lamp and switch con-
nector.
(7) Remove the glove box lamp and switch.
INSTALLATION
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.
(1) Position the glove box lamp and switch to the
instrument panel.
(2) Reconnect the instrument panel wire harness
connector to the glove box lamp and switch connector.
(3) Align the glove box lamp and switch housing
with the mounting hole in the instrument panel
glove box opening upper reinforcement.
(4) Push the glove box lamp and switch into the
mounting hole until the retaining latches are fully
engaged.
(5) Install the lower right center bezel onto the
instrument panel. (Refer to 23 - BODY/INSTRU-
MENT PANEL - INSTALLATION) for the proce-
dures.
(6) Roll the glove box back up into the instrument
panel.(Refer to 23 - BODY/INSTRUMENT PANEL/
GLOVE BOX - INSTALLATION) for the procedures.
(7) Reconnect the battery negative cable.
Fig. 1 Glove Box Lamp and Switch Remove/Install
1 - GLOVE BOX OPENING UPPER REINFORCEMENT
2 - WIRE HARNESS CONNECTOR
3 - GLOVE BOX LAMP & SWITCH
4-LATCH
5 - MOUNTING HOLE
WJLAMPS/LIGHTING - INTERIOR 8L - 31
DOOR AJAR SWITCH (Continued)