2003 JEEP GRAND CHEROKEE Head lamps

(4) Loosen the battery positive cable terminal
clamp pinch-bolt hex nut.
(5) Disconnect the battery positive cable terminal
clamp from the battery positive terminal post. If nec-
essary, use a battery terminal puller to remove the
terminal clamp from the battery post.
(6) Unlatch and open the cover on the Power Dis-
tribution Center (PDC).
(7) Remove the two nuts that secure the battery
positive cable and generator output cable eyelet ter-
minal to the B(+) terminal studs in the PDC.
(8) Remove the battery positive cable and genera-
tor output cable eyelet terminal from the B(+) termi-
nal studs in the PDC.
(9) Disconnect the battery wire harness connector
from the right headlamp and dash wire harness con-
nector located near the front of the battery.
(10) Remove the screw that secures the battery
negative cable eyelet terminal to the inner fender
shield near the front of the battery.
(11) On models with the 4.7L engine, remove the
nut that secures the battery harness clip to the stud
on the right side of the intake manifold and remove
the clip from the stud.
(12) Unlatch and remove the cover from the gener-
ator output terminal stud housing on the back of the
generator.
(13) Remove the nut that secures the generator
output cable eyelet terminal to the generator output
terminal stud.
(14) Remove the generator output cable eyelet ter-
minal from the generator output terminal stud.
(15) Disconnect the battery wire harness connector
from the generator field terminal connector recepta-
cle on the back of the generator.(16) Remove the screw that secures the battery
negative cable ground eyelet terminal to the right
side of the engine block.
(17) Remove the nut that secures the battery pos-
itive cable eyelet terminal to the B(+) terminal stud
on the starter solenoid.
(18) Remove the battery positive cable eyelet ter-
minal from the B(+) terminal stud on the starter
solenoid.
(19) Disconnect the battery wire harness connector
from the connector receptacle on the starter solenoid.
(20) Remove the battery wire harness from the
engine compartment.
INSTALLATION
Both the battery negative cable and the battery
positive cable are serviced in the battery wire har-
ness. If either battery cable is damaged or faulty, the
battery wire harness unit must be replaced.
(1) Clean and inspect the battery cable terminal
clamps and the battery terminal posts.
(2) Position the battery wire harness into the
engine compartment (Fig. 23) or (Fig. 24).
(3) Reconnect the battery wire harness connector
to the connector receptacle on the starter solenoid.
(4) Install the battery positive cable eyelet termi-
nal onto the B(+) terminal stud on the starter sole-
noid.Fig. 22 TEST GROUND CIRCUIT RESISTANCE -
TYPICAL
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
Fig. 23 Battery Cables - 4.0L Engine
1 - BATTERY POSITIVE CABLE
2 - BATTERY NEGATIVE CABLE
3 - CLIPS
8F - 20 BATTERY SYSTEMWJ
BATTERY CABLE (Continued)

(5) Install and tighten the nut that secures the
battery positive cable eyelet terminal to the B(+) ter-
minal stud on the starter solenoid. Tighten the nut to
11.3 N´m (100 in. lbs.).
(6) Install and tighten the screw that secures the
battery negative cable ground eyelet terminal to the
right side of the engine block. Tighten the screw to
10.2 N´m (90 in. lbs.) for 4.0L engines, or 13.0 N´m
(115 in. lbs.) for 4.7L engines.
(7) Reconnect the battery wire harness connector
to the generator field terminal connector receptacle
on the back of the generator.
(8) Install the generator output cable eyelet termi-
nal onto the generator output terminal stud.
(9) Install and tighten the nut that secures the
generator output cable eyelet terminal to the genera-
tor output terminal stud. Tighten the nut to 10.7
N´m (95 in. lbs.).
(10) Position the cover for the generator output
terminal stud housing onto the back of the generator
and snap it into place.
(11) On models with the 4.7L engine, install the
battery harness clip onto the stud on the right side of
the intake manifold, then install and tighten the nut
that secures the clip to the stud. Tighten the nut to
11.3 N´m (100 in. lbs.).
(12) Install and tighten the screw that secures the
battery negative cable eyelet terminal to the inner
fender shield near the front of the battery. Tighten
the screw to 28.2 N´m (250 in. lbs.).(13) Reconnect the battery wire harness connector
to the right headlamp and dash wire harness connec-
tor located near the front of the battery.
(14) Install the battery positive cable and genera-
tor output cable eyelet terminal onto the PDC B(+)
terminal studs.
(15) Install and tighten the two nuts that secure
the battery positive cable and generator output cable
eyelet terminal to the PDC B(+) terminal studs.
Tighten the nuts to 11.3 N´m (100 in. lbs.).
(16) Close and latch the PDC cover.
(17) Reconnect the battery positive cable terminal
clamp to the battery positive terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 6.8 N´m (60
in. lbs.).
(18) Reconnect the battery negative cable terminal
clamp to the battery negative terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 6.8 N´m (60
in. lbs.).
(19) Apply a thin coating of petroleum jelly or
chassis grease to the exposed surfaces of the battery
cable terminal clamps and the battery terminal
posts.BATTERY TRAY
DESCRIPTION
The battery is mounted in a molded plastic battery
tray and support unit (Fig. 25) located in the right
front corner of the engine compartment. The battery
tray and support unit is secured at the rear with a
nut to a stud on the front wheelhouse inner panel, at
the outboard side with a screw to the side cowl rein-
forcement panel, and at the front with a screw
through a U-nut on a bracket of the radiator support.
The battery tray and support unit also includes
three upright stanchions that are molded into the
outboard side of the unit. These stanchions support
the Power Distribution Center (PDC). Refer to
Power Distribution Centerin the Power Distribu-
tion section of this service manual for more informa-
tion on the PDC.
A hole in the bottom of the battery tray is fitted
with a battery temperature sensor. Refer toBattery
Temperature Sensorin the Charging section of
this service manual for more information on the bat-
tery temperature sensor. Refer toBattery Hold
Downin this section of the service manual for more
information on the battery hold down hardware.
Fig. 24 Battery Cables - 4.7L Engine
1 - BATTERY POSITIVE CABLE
2 - BATTERY NEGATIVE CABLE
3 - CLIPS
WJBATTERY SYSTEM 8F - 21
BATTERY CABLE (Continued)

The VFD is diagnosed using the EMIC self-diag-
nostic actuator test. (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - DIAGNOSIS AND
TESTING). Proper testing of the PCI data bus and
the data bus message inputs to the EMIC that con-
trol the VFD functions requires the use of a DRBIIIt
scan tool. Refer to the appropriate diagnostic infor-
mation. Specific operation details for the odometer
and trip odometer functions of the VFD may be found
elsewhere in this service information.
INDICATORS
Indicators are located in various positions within
the EMIC and are all connected to the EMIC circuit
board. The turn signal indicators are hard wired. The
brake indicator is controlled by PCI data bus mes-
sages from the Controller Antilock Brake (CAB) as
well as by hard wired park brake switch and brake
fluid level switch inputs to the EMIC. The Malfunc-
tion Indicator Lamp (MIL) is normally controlled by
PCI data bus messages from the Powertrain Control
Module (PCM); however, if the EMIC loses PCI data
bus communication, the EMIC circuitry will automat-
ically turn the MIL on until PCI data bus communi-
cation is restored. The EMIC uses PCI data bus
messages from the Airbag Control Module (ACM), the
BCM, the PCM, the CAB, the Sentry Key Immobi-
lizer Module (SKIM), and the Transmission Control
Module (TCM) to control all of the remaining indica-
tors.
The various indicators are controlled by different
strategies; some receive fused ignition switch output
from the EMIC circuitry and have a switched ground,
others are grounded through the EMIC circuitry and
have a switched battery feed, while still others are
completely controlled by the EMIC microprocessor
based upon various hard wired and electronic mes-
sage inputs. Some indicators are illuminated at a
fixed intensity, while the illumination intensity of
others is synchronized with that of the EMIC general
illumination lamps.
The hard wired indicators are diagnosed using con-
ventional diagnostic methods. The EMIC and PCI
bus message controlled indicators are diagnosed
using the EMIC self-diagnostic actuator test. (Refer
to 8 - ELECTRICAL/INSTRUMENT CLUSTER -
DIAGNOSIS AND TESTING). Proper testing of the
PCI data bus and the electronic data bus message
inputs to the EMIC that control each indicator
require the use of a DRBIIItscan tool. Refer to the
appropriate diagnostic information. Specific details of
the operation for each indicator may be found else-
where in this service information.CLUSTER ILLUMINATION
Two types of general cluster illumination are avail-
able in this model. Base versions of the EMIC have
several incandescent illumination lamps, while pre-
mium versions of the EMIC have a single electro-lu-
minescent lamp. Both types of lamps provide cluster
back lighting whenever the exterior lighting is
turned On with the control knob on the left (lighting)
multi-function switch control stalk. The illumination
intensity of these lamps is adjusted by the EMIC
microprocessor based upon electronic dimming level
messages received from the Body Control Module
(BCM) over the PCI data bus. The BCM provides
electronic dimming level messages to the EMIC
based upon internal programming and inputs it
receives when the control ring on the left (lighting)
multi-function switch control stalk is rotated (down
to dim, up to brighten) to one of six available minor
detent positions.
The incandescent illumination lamps receive bat-
tery current at all times, while the ground for these
lamps is controlled by a 12-volt Pulse Width Modu-
lated (PWM) output of the EMIC electronic circuitry.
The illumination intensity of these bulbs and of the
vacuum-fluorescent electronic display are controlled
by the instrument cluster microprocessor based upon
dimming level messages received from the Body Con-
trol Module (BCM) over the PCI data bus. The BCM
uses inputs from the headlamp and panel dimmer
switches within the left (lighting) multi-function
switch control stalk and internal programming to
decide what dimming level message is required. The
BCM then sends the proper dimming level messages
to the EMIC over the PCI data bus.
The electro-luminescent lamp unit consists of lay-
ers of phosphor, carbon, idium tin oxide, and dielec-
tric applied by a silk-screen process between two
polyester membranes and includes a short pigtail
wire and connector. The lamp pigtail wire is con-
nected to a small connector receptacle on the EMIC
circuit board through a small clearance hole in the
cluster housing rear cover. The EMIC electronic cir-
cuitry also uses a PWM strategy to control the illu-
mination intensity of this lamp; however, the EMIC
powers this lamp with an Alternating Current (AC)
rated at 80 volts rms (root mean squared) and 415
Hertz, which excites the phosphor particles causing
them to luminesce.
The BCM also has several hard wired panel lamp
driver outputs and sends the proper panel lamps
dimming level messages over the PCI data bus to
coordinate the illumination intensity of all of the
instrument panel lighting and the VFDs of other
electronic modules on the PCI data bus. Vehicles
equipped with the Auto Headlamps option have an
automatic parade mode. In this mode, the BCM uses
8J - 6 INSTRUMENT CLUSTERWJ
INSTRUMENT CLUSTER (Continued)

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

proper percent tank full messages to the instrument
cluster. For further diagnosis of the fuel gauge or the
instrument cluster circuitry that controls the gauge,
(Refer to 8 - ELECTRICAL/INSTRUMENT CLUS-
TER - 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 fuel gauge, a
DRBIIItscan tool is required. Refer to the appropri-
ate diagnostic information.
HIGH BEAM INDICATOR
DESCRIPTION
A high beam indicator is standard equipment on
all instrument clusters. The high beam indicator is
located near the upper edge of the instrument clus-
ter, between the tachometer and the speedometer.
The high beam indicator consists of an International
Control and Display Symbol icon for ªHigh Beamº
imprinted on a blue 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 indicator from being clearly visible when it is not
illuminated. The icon appears silhouetted against a
blue 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 elec-
tronic circuit board. When the exterior lighting is
turned On, the illumination intensity of the high
beam indicator is dimmable, which is adjusted using
the panel lamps dimmer control ring on the control
stalk of the left multi-function switch. The high beam
indicator lens is serviced as a unit with the instru-
ment cluster lens, hood and mask unit.
OPERATION
The high beam indicator gives an indication to the
vehicle operator whenever the headlamp high beams
are illuminated. 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
Body Control Module (BCM) over the Programmable
Communications Interface (PCI) data bus. The high
beam indicator bulb is completely controlled by the
instrument cluster logic circuit, and that logic will
allow this indicator to operate whenever the instru-
ment cluster receives a battery current input on the
fused B(+) circuit. Therefore, the indicator can be
illuminated regardless of the ignition switch position.
The LED only illuminates when it is provided a path
to ground by the instrument cluster transistor. Theinstrument cluster will turn on the high beam indi-
cator for the following reasons:
²High Beam Indicator Lamp-On Message-
Each time the cluster receives a high beam indicator
lamp-on message from the BCM indicating that the
headlamp high beams are turned On, the high beam
indicator will be illuminated. The indicator remains
illuminated until the cluster receives a high beam
indicator lamp-off message from the BCM.
²Actuator Test- Each time the cluster is put
through the actuator test, the high beam indicator
will be turned on for the duration of the test to con-
firm the functionality of the bulb and the cluster con-
trol circuitry.
The BCM continually monitors the exterior light-
ing (left multi-function) switch to determine the
proper outputs to the headlamp low beam and high
beam relays. The BCM then sends the proper high
beam indicator lamp-on and lamp-off messages to the
instrument cluster. If the high beam indicator fails to
light during the actuator test, replace the bulb with a
known good unit. For further diagnosis of the high
beam indicator or the instrument cluster circuitry
that controls the indicator, (Refer to 8 - ELECTRI-
CAL/INSTRUMENT CLUSTER - DIAGNOSIS AND
TESTING). For proper diagnosis of the headlamp
system, the BCM, the PCI data bus, or the electronic
message inputs to the instrument cluster that control
the high beam indicator, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
LOW FUEL INDICATOR
DESCRIPTION
A low fuel indicator is standard equipment on all
instrument clusters. The low fuel indicator is located
near the left edge of the instrument cluster, to the left
of the tachometer. The low fuel indicator consists of an
International Control and Display Symbol icon for
ªFuelº 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 visible when the
indicator is not illuminated. The icon appears silhou-
etted against an amber field through the translucent
outer layer of the overlay when the indicator is illumi-
nated from behind by a replaceable incandescent bulb
and bulb holder unit located on the instrument cluster
electronic circuit board. When the exterior lighting is
turned On, the illumination intensity of the low fuel
indicator is dimmable, which is adjusted using the
panel lamps dimmer control ring on the control stalk
of the left multi-function switch. The low fuel indica-
8J - 22 INSTRUMENT CLUSTERWJ
FUEL GAUGE (Continued)

LAMPS
TABLE OF CONTENTS
page page
LAMPS/LIGHTING - EXTERIOR............... 1LAMPS/LIGHTING - INTERIOR............... 28
LAMPS/LIGHTING - EXTERIOR
TABLE OF CONTENTS
page page
LAMPS/LIGHTING - EXTERIOR
DESCRIPTION - TURN SIGNAL & HAZARD
WARNING SYSTEM.....................2
OPERATION - TURN SIGNAL & HAZARD
WARNING SYSTEM.....................2
DIAGNOSIS AND TESTING - TURN SIGNAL &
HAZARD WARNING SYSTEMS............3
SPECIFICATIONS
EXTERIOR LAMPS.....................4
AUTO HEADLAMP SENSOR
DIAGNOSIS AND TESTING - AUTO
HEADLAMP SENSOR (AHL)..............4
REMOVAL.............................4
INSTALLATION..........................4
BRAKE LAMP SWITCH
DESCRIPTION..........................5
OPERATION............................5
DIAGNOSIS AND TESTING Ð BRAKE LAMP
SWITCH.............................5
REMOVAL.............................5
INSTALLATION..........................5
ADJUSTMENTS
ADJUSTMENT.........................6
CENTER HIGH MOUNTED STOP LAMP
REMOVAL
REMOVAL - BULB......................6
REMOVAL - CHMSL....................6
INSTALLATION
INSTALLATION - BULB..................6
INSTALLATION - CHMSL.................7
COMBINATION FLASHER
DESCRIPTION..........................7
OPERATION............................7
REMOVAL.............................9
INSTALLATION..........................9
DAYTIME RUNNING LAMP MODULE
DESCRIPTION..........................9OPERATION............................9
REMOVAL.............................9
INSTALLATION..........................9
FOG LAMP
REMOVAL.............................10
INSTALLATION.........................10
FOG LAMP UNIT
REMOVAL.............................10
INSTALLATION.........................10
ADJUSTMENTS
FOG LAMP ADJUSTMENT...............10
HEADLAMP
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING Ð HEADLAMP
SYSTEM............................12
DIAGNOSIS AND TESTING Ð HEADLAMP . . 14
REMOVAL - BULB.......................14
INSTALLATION - BULB...................15
HEADLAMP SWITCH
DESCRIPTION.........................15
OPERATION...........................15
DIAGNOSIS AND TESTING Ð HEADLAMP
SWITCH............................15
HEADLAMP UNIT
REMOVAL.............................16
INSTALLATION.........................16
ADJUSTMENTS........................16
LICENSE PLATE LAMP
REMOVAL
REMOVAL - BULB.....................17
REMOVAL - LAMP.....................18
INSTALLATION
INSTALLATION - BULB.................18
INSTALLATION - LAMP.................18
WJLAMPS 8L - 1

LICENSE PLATE LAMP UNIT
REMOVAL.............................18
INSTALLATION.........................19
LEFT MULTI-FUNCTION SWITCH
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - LEFT MULTI -
FUNCTION SWITCH...................20
REMOVAL
REMOVAL - LEFT MULTI-FUNCTION
SWITCH............................22
REMOVAL - MULTI-FUNCTION SWITCH
MOUNTING HOUSING..................22
INSTALLATION
INSTALLATION - LEFT MULTI-FUNCTION
SWITCH............................23
INSTALLATION - MULTI-FUNCTION SWITCH
MOUNTING HOUSING..................24
PARK/TURN SIGNAL LAMP
REMOVAL - BULBS.....................25INSTALLATION - BULBS..................25
TAIL LAMP
DESCRIPTION.........................25
OPERATION...........................25
REMOVAL
REMOVAL - BULBS....................25
REMOVAL - LAMP.....................25
INSTALLATION
INSTALLATION - BULBS................26
INSTALLATION - LAMP.................26
TURN SIGNAL CANCEL CAM
DESCRIPTION.........................26
OPERATION...........................26
UNDERHOOD LAMP
REMOVAL
REMOVAL - BULB.....................27
REMOVAL - LAMP.....................27
INSTALLATION
INSTALLATION - BULB.................27
INSTALLATION - LAMP.................27
LAMPS/LIGHTING - EXTERIOR
DESCRIPTION - TURN SIGNAL & HAZARD
WARNING SYSTEM
The turn signal and hazard warning system
includes the following major components, which are
described in further detail elsewhere in this service
information:
²Combination Flasher
²Front Side Marker Lamps
²Hazard Warning Switch
²Turn Signal Cancel Cam
²Turn Signal Indicators
²Turn Signal Lamps
²Turn Signal Switch
The turn signal and hazard warning systems also
provide the following features:
²Flash Lights with Lock- This customer pro-
grammable feature flashes the hazard warning lamps
to provide optical verification that the Remote Key-
less Entry (RKE) System has received a valid Lock or
Unlock request from an RKE transmitter. (Refer to 8
- ELECTRICAL/POWER LOCKS - DESCRIPTION -
REMOTE KEYLESS ENTRY SYSTEM).
²Panic Mode Optical Alert- This feature
flashes the hazard warning lamps to provide an opti-
cal alert when the Remote Keyless Entry (RKE) Sys-
tem panic mode is activated by depressing the Panic
button on an RKE transmitter. (Refer to 8 - ELEC-
TRICAL/POWER LOCKS - DESCRIPTION -
REMOTE KEYLESS ENTRY SYSTEM).
²Turn Signal On Warning- This feature pro-
vides the vehicle operator with both visual and audi-
ble reminders when a turn signal has been left
turned on for an extended period. (Refer to 8 - ELEC-TRICAL/OVERHEAD CONSOLE/ELECTRONIC
VEHICLE INFO CENTER - DESCRIPTION).
²Vehicle Theft Security System (VTSS) Opti-
cal Alarm- This feature flashes the hazard warning
lamps to provide an optical alarm when the VTSS is
armed and activated by an unauthorized entry into
the vehicle. (Refer to 8 - ELECTRICAL/VEHICLE
THEFT SECURITY - DESCRIPTION - VEHICLE
THEFT SECURITY SYSTEM).
OPERATION - TURN SIGNAL & HAZARD
WARNING SYSTEM
The turn signal system operates on battery current
received on a fused ignition switch output (run) cir-
cuit so that the turn signals will only operate with
the ignition switch in the On position. The hazard
warning system operates on non-switched battery
current received on a fused B(+) circuit so that the
hazard warning remains operational regardless of
the ignition switch position. When the turn signal
system is activated, the circuitry of the turn signal
switch and the combination flasher will cause the
selected (right or left) turn signal indicator, front
park/turn signal lamp, front side marker lamp and
rear tail/stop/turn signal lamp to flash on and off.
When the hazard warning system is activated, the
circuitry of the hazard warning switch and the com-
bination flasher will cause both the right side and
the left side turn signal indicators, front park/turn
signal lamps, front side marker lamps and rear tail/
stop/turn signal lamps to flash on and off.
The Body Control Module (BCM) can also activate
the hazard warning system lamps by energizing the
combination flasher through a single hard wired con-
nection to the hazard warning switch sense circuit.
The BCM grounds the circuit to energize and de-en-
8L - 2 LAMPS/LIGHTING - EXTERIORWJ

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)