2003 JEEP GRAND CHEROKEE Hood prop

pletely controlled by the instrument cluster logic cir-
cuit, and that logic will only allow this indicator to
operate when the instrument cluster receives a bat-
tery current input on the fused ignition switch out-
put (run-start) circuit. Therefore, the indicator will
always be off when the ignition switch is in any posi-
tion except On or Start. The bulb only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the overdrive off indicator for the following
reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the overdrive off indicator
is illuminated for about three seconds as a bulb test.
²Overdrive Off Indicator Lamp-On Message-
Each time the cluster receives an overdrive off indi-
cator lamp-on message from the PCM or TCM indi-
cating that the Off position of the overdrive off
switch has been selected, the overdrive off indicator
will be illuminated. The indicator remains illumi-
nated until the cluster receives an overdrive off indi-
cator lamp-off message from the PCM or TCM, or
until the ignition switch is turned to the Off position,
whichever occurs first.
²Actuator Test- Each time the cluster is put
through the actuator test, the overdrive off 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 PCM or TCM continually monitors the over-
drive off switch to determine the proper outputs to
the automatic transmission. The PCM or TCM then
sends the proper overdrive off indicator lamp-on or
lamp-off messages to the instrument cluster. If the
overdrive off indicator fails to light during the bulb
test, replace the bulb with a known good unit. For
further diagnosis of the overdrive off indicator or the
instrument cluster circuitry that controls the indica-
tor, (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). For
proper diagnosis of the overdrive control system, the
PCM, the TCM, the PCI data bus, or the electronic
message inputs to the instrument cluster that control
the overdrive off indicator, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
REAR FOG LAMP INDICATOR
DESCRIPTION
A rear fog lamp indicator is standard equipment on
all instrument clusters, but is only functional on
vehicles equipped with optional rear fog lamps,
which are available only in certain international
markets where they are required. The rear fog lampindicator is located on the left edge of the instrument
cluster, to the left of the tachometer. The rear fog
lamp indicator consists of an International Control
and Display Symbol icon for ªRear Fog Lightº
imprinted on an amber lens. The lens is located
behind a cutout in the opaque layer of the instru-
ment cluster overlay. The dark outer layer of the
overlay prevents the indicator from being clearly vis-
ible when it is not illuminated. The icon appears sil-
houetted against an amber field through the
translucent outer layer of the overlay when the indi-
cator is illuminated 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 rear fog lamp indicator is dimmable,
which is adjusted using the panel lamps dimmer con-
trol ring on the control stalk of the left multi-func-
tion switch. The rear fog lamp indicator lens is
serviced as a unit with the instrument cluster lens,
hood and mask unit.
OPERATION
The rear fog lamp indicator gives an indication to
the vehicle operator whenever the rear fog lamps are
illuminated. 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 Body Control
Module (BCM) over the Programmable Communica-
tions Interface (PCI) data bus. The rear fog lamp
indicator bulb is completely controlled by the instru-
ment cluster logic circuit, and that logic will allow
this indicator to operate whenever the instrument
cluster receives a battery current input on the fused
B(+) circuit. Therefore, the indicator can be illumi-
nated regardless of the ignition switch position. The
bulb only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the rear fog lamp
indicator for the following reasons:
²Rear Fog Lamp Indicator Lamp-On Mes-
sage- Each time the cluster receives a rear fog lamp
indicator lamp-on message from the BCM indicating
that the rear fog lamps are turned On, the rear fog
lamp indicator will be illuminated. The indicator
remains illuminated until the cluster receives a rear
fog lamp indicator lamp-off message from the BCM.
²Actuator Test- Each time the cluster is put
through the actuator test, the rear fog lamp 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 rear fog lamp relay. The BCM
WJINSTRUMENT CLUSTER 8J - 27
OVERDRIVE OFF INDICATOR (Continued)

then sends the proper rear fog lamp indicator
lamp-on and lamp-off messages to the instrument
cluster. If the rear fog lamp indicator fails to light
during the actuator test, replace the bulb with a
known good unit. For further diagnosis of the rear
fog lamp 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 rear fog lamp
system, the BCM, the PCI data bus, or the electronic
message inputs to the instrument cluster that control
the rear fog lamp indicator, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
SEATBELT INDICATOR
DESCRIPTION
A seatbelt indicator is standard equipment on all
instrument clusters. The seatbelt indicator is located
near the lower edge of the instrument cluster, to the
left of the tachometer. The seatbelt indicator consists
of an International Control and Display Symbol icon
for ªSeat Beltº imprinted on a red 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 a red field through the
translucent outer layer of the overlay when it is illu-
minated from behind by a Light Emitting Diode
(LED), which is soldered onto the instrument cluster
electronic circuit board. The seatbelt indicator lens is
serviced as a unit with the instrument cluster lens,
hood and mask unit.
OPERATION
The seatbelt indicator gives an indication to the
vehicle operator of the status of the driver side front
seatbelt. This indicator is controlled by a transistor
on the instrument cluster electronic circuit board
based upon cluster programming. On models
equipped with airbags the indicator is also controlled
by electronic messages received by the cluster from
the Airbag Control Module (ACM) over the Program-
mable Communications Interface (PCI) data bus. The
seatbelt indicator Light Emitting Diode (LED) is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indicator to
operate when the instrument cluster receives a bat-
tery current input on the fused ignition switch out-
put (run-start) circuit. Therefore, the indicator willalways be off when the ignition switch is in any posi-
tion except On or Start. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the seatbelt indicator for the following rea-
sons:
²Seatbelt Reminder Function- Each time the
cluster receives a battery current input on the fused
ignition switch output (run-start) circuit, the indica-
tor will be illuminated as a seatbelt reminder for
about six seconds, or until the ignition switch is
turned to the Off position, whichever occurs first.
This reminder function will occur regardless of the
status of the electronic seat belt lamp-on or lamp-off
messages received by the cluster from the ACM.
²Seat Belt Indicator Lamp-On Message-On
models equipped with airbags, following the seatbelt
reminder function, each time the cluster receives a
seat belt indicator lamp-on message from the ACM
indicating the driver side front seat belt is not fas-
tened with the ignition switch in the Start or On
positions, the seatbelt indicator will be illuminated.
The indicator remains illuminated until the cluster
receives a seat belt indicator lamp-off message from
the ACM, or until the ignition switch is turned to the
Off position, whichever occurs first.
²Actuator Test- Each time the cluster is put
through the actuator test, the seatbelt indicator will
be turned on for the duration of the test to confirm
the functionality of the LED and the cluster control
circuitry.
The instrument cluster continually monitors the
status of the ignition switch through the hard wired
fused ignition switch output (run-start) circuit to
determine when to provide the seatbelt reminder
function. On models equipped with airbags, the ACM
continually monitors the status of both front seat belt
switches to determine the proper airbag system
response to a frontal impact of the vehicle. The ACM
then sends the proper seatbelt indicator lamp-on and
lamp-off messages to the instrument cluster based
upon the status of the driver side front seat belt
switch input. For further diagnosis of the seatbelt
indicator or the instrument cluster circuitry that con-
trols the indicator, (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - DIAGNOSIS AND
TESTING). For proper diagnosis of the seatbelt
switches, the ACM, the PCI data bus, or the elec-
tronic message inputs to the instrument cluster that
control the seatbelt indicator, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
8J - 28 INSTRUMENT CLUSTERWJ
REAR FOG LAMP INDICATOR (Continued)

SHIFT INDICATOR (TRANSFER
CASE)
DESCRIPTION
A part time indicator is standard equipment on all
instrument clusters, but is only functional on vehi-
cles equipped with the standard equipment Selec-
Trac four-wheel drive system. The part time indicator
is located near the right edge of the instrument clus-
ter, to the right of the speedometer. The part time
indicator consists of the words ªPART TIMEº
imprinted on an amber lens. The lens is located
behind a cutout in the opaque layer of the instru-
ment cluster overlay. The dark outer layer of the
overlay prevents the indicator from being clearly vis-
ible when it is not illuminated. The words ªPART
TIMEº appear 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 part time indicator lens is serviced as a
unit with the instrument cluster lens, hood and mask
unit.
OPERATION
The part time indicator gives an indication to the
vehicle operator that a four-wheel drive part time
operating mode of the transfer case is selected. On
vehicles with the standard equipment Selec-Trac
four-wheel drive system, the part time indicator illu-
minates when the NV-242 transfer case is engaged in
either the4X4Part Time or 4 Lo positions. This
indicator is controlled by a transistor on the instru-
ment cluster electronic circuit board based upon clus-
ter programming and electronic messages received by
the cluster from the Powertrain Control Module
(PCM) over the Programmable Communications
Interface (PCI) data bus. The part time indicator
bulb is completely controlled by the instrument clus-
ter logic circuit, and that logic will only allow this
indicator to operate when the instrument cluster
receives a battery current input on the fused ignition
switch output (run-start) circuit. Therefore, the indi-
cator will always be off when the ignition switch is in
any position except On or Start. The bulb only illu-
minates when it is provided a path to ground by the
instrument cluster transistor. The instrument cluster
will turn on the part time indicator for the following
reasons:
²Part Time Indicator Lamp-On Message-
Each time the cluster receives a part time indicator
lamp-on message from the PCM indicating that a
four-wheel drive part time position of the transfer
case has been selected, the part time indicator will beilluminated. The indicator remains illuminated until
the cluster receives a part time indicator lamp-off
message from the PCM.
²Actuator Test- Each time the cluster is put
through the actuator test, the part time 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 transfer case
switch to determine the driveline operating mode.
The PCM then sends the proper part time indicator
lamp-on and lamp-off messages to the instrument
cluster. If the part time indicator fails to light during
the actuator test, replace the bulb with a known good
unit. For further diagnosis of the part time indicator
or the instrument cluster circuitry that controls the
indicator, (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). For
proper diagnosis of the transfer case switch, the
PCM, the PCI data bus, or the electronic message
inputs to the instrument cluster that control the part
time indicator, a DRBIIItscan tool is required. Refer
to the appropriate diagnostic information.
SKIS INDICATOR
DESCRIPTION
A Sentry Key Immobilizer System (SKIS) indicator
is standard equipment on all instrument clusters, but
is only operational on vehicles equipped with the
optional SKIS. The SKIS indicator is located in the
upper right corner of the instrument cluster, to the
right of the speedometer. The SKIS indicator consists
of a graphical representation or icon of a circled and
crossed-out key 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 indicator from being clearly
visible when it is not illuminated. The icon appears
silhouetted against an amber field through the trans-
lucent outer layer of the overlay when it is illumi-
nated from behind by an incandescent bulb and bulb
holder unit located on the instrument cluster elec-
tronic circuit board. The SKIS indicator lens is ser-
viced as a unit with the instrument cluster lens, hood
and mask unit.
OPERATION
The Sentry Key Immobilizer System (SKIS) indica-
tor gives an indication to the vehicle operator of the
status of the SKIS. 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 Sen-
try Key Immobilizer Module (SKIM) over the
WJINSTRUMENT CLUSTER 8J - 29

Control Module (PCM) over the Programmable Com-
munications Interface (PCI) data bus. The tachome-
ter is an air core magnetic unit that receives battery
current on the instrument cluster electronic circuit
board through the fused ignition switch output (run-
start) circuit whenever the ignition switch is in the
On or Start positions. The cluster is programmed to
move the gauge needle back to the low end 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:
²Engine Speed Message- Each time the cluster
receives an engine speed message from the PCM it
will calculate the correct engine speed reading and
position the gauge needle at that speed position on
the gauge scale. The cluster will receive a new
engine speed message and reposition the gauge
pointer accordingly about every 86 milliseconds. The
gauge needle will continue to be positioned at the
actual engine speed position on the gauge scale until
the ignition switch is turned to the Off position.
²Communication Error- If the cluster fails to
receive an engine speed message, it will hold the
gauge needle at the last indication for about six sec-
onds, or until the ignition switch is turned to the Off
position, whichever occurs first. If a new engine
speed message is not received after about six sec-
onds, the gauge needle will return to the far left
(low) end of the 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 crankshaft posi-
tion sensor to determine the engine speed, then
sends the proper engine speed messages to the
instrument cluster. For further diagnosis of the
tachometer or the instrument cluster circuitry that
controls the gauge, (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - DIAGNOSIS AND TEST-
ING). For proper diagnosis of the crankshaft position
sensor, the PCM, the PCI data bus, or the electronic
message inputs to the instrument cluster that control
the tachometer, a DRBIIItscan tool is required.
Refer to the appropriate diagnostic information.
TRANS TEMP INDICATOR
DESCRIPTION
A transmission over-temperature indicator is stan-
dard equipment on all gasoline engine instrument
clusters. The transmission over-temperature indica-
tor is located near the lower right corner of theinstrument cluster, to the right of the speedometer.
The transmission over-temperature indicator consists
of the words ªTRANS OVER TEMPº 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 indi-
cator from being clearly visible when it is not illumi-
nated. The words ªTRANS OVER TEMPº appear
silhouetted against an amber field through the trans-
lucent outer layer of the overlay when the indicator
is illuminated from behind by a replaceable incandes-
cent bulb and bulb holder unit located on the instru-
ment cluster electronic circuit board. The
transmission over-temperature indicator lens is ser-
viced as a unit with the instrument cluster lens, hood
and mask unit.
OPERATION
The transmission over-temperature indicator gives
an indication to the vehicle operator when the trans-
mission fluid temperature is excessive, which may
lead to accelerated transmission component wear or
failure. This indicator is controlled by a transistor on
the instrument cluster electronic circuit board based
upon cluster programming and electronic messages
received by the cluster over the Programmable Com-
munications Interface (PCI) data bus. These mes-
sages are sent by the Powertrain Control Module
(PCM) or by the Transmission Control Module
(TCM), depending on the model of the automatic
transmission. The transmission over-temperature
indicator bulb is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
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 provided a path to ground
by the instrument cluster transistor. The instrument
cluster will turn on the transmission over-tempera-
ture indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the transmission over-tem-
perature indicator is illuminated for about three sec-
onds as a bulb test.
²Trans Over-Temp Indicator Lamp-On Mes-
sage- Each time the cluster receives a trans over-
temp indicator lamp-on message from the PCM or
TCM indicating that the transmission fluid tempera-
ture is 135É C (275É F) or higher, the transmission
over-temperature indicator will be illuminated. The
indicator remains illuminated until the cluster
receives a trans over-temp indicator lamp-off mes-
sage from the PCM or TCM, or until the ignition
8J - 32 INSTRUMENT CLUSTERWJ
TACHOMETER (Continued)

switch is turned to the Off position, whichever occurs
first.
²Actuator Test- Each time the cluster is put
through the actuator test, the transmission over-tem-
perature 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 or TCM continually monitors the trans-
mission temperature sensor to determine the trans-
mission operating condition. The PCM or TCM then
sends the proper trans over-temp indicator lamp-on
or lamp-off messages to the instrument cluster. If the
transmission over-temperature indicator fails to light
during the bulb test, replace the bulb with a known
good unit. If the instrument cluster turns on the
transmission over-temperature indicator due to a
high transmission oil temperature condition, it may
indicate that the transmission or the transmission
cooling system are being overloaded or that they
require service. For further diagnosis of the trans-
mission over-temperature indicator or the instrument
cluster circuitry that controls the indicator, (Refer to
8 - ELECTRICAL/INSTRUMENT CLUSTER - DIAG-
NOSIS AND TESTING). For proper diagnosis of the
transmission temperature sensor, the PCM, the
TCM, the PCI data bus, or the electronic message
inputs to the instrument cluster that control the
transmission over-temperature indicator, a DRBIIIt
scan tool is required. Refer to the appropriate diag-
nostic information.
TURN SIGNAL INDICATOR
DESCRIPTION
Two turn signal indicators, one right and one left,
are standard equipment on all instrument clusters.
The turn signal indicators are located near the upper
edge of the instrument cluster, the left one is left of
the tachometer, and the right one is right of the
speedometer. Each turn signal indicator consists of
an International Control and Display Symbol icon for
ªTurn Warningº imprinted on a green lens. Each lens
is located behind a dedicated cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents these icons from
being clearly visible when they are not illuminated.
The icons appear silhouetted against a green 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 turn signal indicator lenses are serviced
as a unit with the instrument cluster lens, hood and
mask unit.
OPERATION
The turn signal indicators give an indication to the
vehicle operator that the turn signal (left or right
indicator flashing) or hazard warning (both left and
right indicators flashing) have been selected and are
operating. These indicators are controlled by two
individual hard wired inputs from the combination
flasher circuitry to the instrument cluster electronic
circuit board. Each turn signal indicator bulb is
grounded on the instrument cluster electronic circuit
board at all times; therefore, these indicators remain
functional regardless of the ignition switch position.
Each indicator bulb will only illuminate when it is
provided with battery current by the combination
flasher in the Junction Block (JB).
The turn signal indicators are connected in parallel
with the other turn signal circuits. This arrangement
allows the turn signal indicators to remain func-
tional, regardless of the condition of the other cir-
cuits in the turn signal and hazard warning systems.
The combination flasher outputs to the instrument
cluster turn signal indicator inputs can be diagnosed
using conventional diagnostic tools and methods. For
more information on the turn signal and hazard
warning system, (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR - OPERATION - TURN
SIGNAL & HAZARD WARNING SYSTEM).
DIAGNOSIS AND TESTING - TURN SIGNAL
INDICATOR
The diagnosis found here addresses an inoperative
turn signal indicator condition. If the problem being
diagnosed is related to inoperative turn signal or
hazard warning lamps, be certain to repair the turn
signal and hazard warning system before attempting
to diagnose or repair the turn signal indicators.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR - DIAGNOSIS AND TESTING - TURN
SIGNAL & HAZARD WARNING SYSTEM). If no
turn signal and hazard warning system problem is
found, the following procedure will help locate an
open in the turn signal indicator circuit. 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.
WJINSTRUMENT CLUSTER 8J - 33
TRANS TEMP INDICATOR (Continued)

inputs to the instrument cluster that control the
wait-to-start indicator, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
WATER-IN-FUEL INDICATOR
DESCRIPTION
A water-in-fuel indicator is only found in the
instrument clusters of vehicles equipped with an
optional diesel engine. The water-in-fuel indicator is
located near the left edge of the instrument cluster,
to the left of the tachometer. The water-in-fuel indi-
cator consists of an International Control and Dis-
play Symbol icon for ªWater in Fuelº imprinted on a
red 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 silhouetted against a
red field through the translucent outer layer of the
overlay when the indicator is illuminated from
behind by a Light Emitting Diode (LED), which is
soldered onto the instrument cluster electronic circuit
board. The water-in-fuel indicator lens is serviced as
a unit with the instrument cluster lens, hood and
mask unit.
OPERATION
The water-in-fuel indicator gives an indication to
the vehicle operator when there is excessive water in
the fuel system. This indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and electronic mes-
sages received by the cluster from the Powertrain
Control Module (PCM) over the Programmable Com-
munications Interface (PCI) data bus. The water-in-
fuel indicator Light Emitting Diode (LED) is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indicator tooperate when the instrument cluster receives a bat-
tery current input on the fused ignition switch out-
put (run-start) circuit. Therefore, the indicator will
always be off when the ignition switch is in any posi-
tion except On or Start. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the water-in-fuel indicator for the following
reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the water-in-fuel indicator
is illuminated for about three seconds as a bulb test.
²Water-In-Fuel Indicator Lamp-On Message-
Each time the cluster receives a water-in-fuel indica-
tor lamp-on message from the PCM indicating there
is excessive water in the diesel fuel system, the
water-in-fuel indicator will be illuminated. The indi-
cator remains illuminated until the cluster receives a
water-in-fuel indicator lamp-off message, or until the
ignition switch is turned to the Off position, which-
ever occurs first.
²Actuator Test- Each time the cluster is put
through the actuator test, the water-in-fuel indicator
will be turned on for the duration of the test to con-
firm the functionality of the LED and the cluster con-
trol circuitry.
The PCM continually monitors the water-in-fuel
sensor to determine whether there is excessive water
in the diesel fuel. The PCM then sends the proper
water-in-fuel indicator lamp-on and lamp-off mes-
sages to the instrument cluster. For further diagnosis
of the water-in-fuel indicator or the instrument clus-
ter circuitry that controls the indicator, (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER - DIAGNO-
SIS AND TESTING). For proper diagnosis of the
water-in-fuel sensor, the PCM, the PCI data bus, or
the electronic message inputs to the instrument clus-
ter that control the water-in-fuel indicator, a
DRBIIItscan tool is required. Refer to the appropri-
ate diagnostic information.
8J - 36 INSTRUMENT CLUSTERWJ
WAIT-TO-START INDICATOR (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)

CONTROL/CENTRAL TIMER MODULE -
DESCRIPTION).
²Combination Flasher (Refer to 8 - ELECTRI-
CAL/LAMPS/LIGHTING - EXTERIOR/COMBINA-
TION FLASHER - DESCRIPTION).
²Door Ajar Switch (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - INTERIOR/DOOR AJAR
SWITCH - DESCRIPTION - DOOR AJAR SWITCH).
²Driver Cylinder Lock Switch (Refer to 8 - ELEC-
TRICAL/POWER LOCKS/DOOR CYLINDER LOCK/
UNLOCK SWITCH - DESCRIPTION).
²Hood Ajar Switch(Refer to 8 - ELECTRICAL/VE-
HICLE THEFT SECURITY/HOOD AJAR SWITCH -
DESCRIPTION).
²Horn Relay (Refer to 8 - ELECTRICAL/HORN/
HORN RELAY - DESCRIPTION).
²Liftgate Ajar Switch (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - INTERIOR/DOOR AJAR
SWITCH - DESCRIPTION - LIFTGATE AJAR
SWITCH).
²Liftgate Flip-Up Glass Ajar Switch(Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - INTERIOR/
DOOR AJAR SWITCH - DESCRIPTION - LIFTGATE
FLIP-UP GLASS AJAR SWITCH).
²Low Beam Headlamp Relay
²VTSS Indicator (Refer to 8 - ELECTRICAL/VE-
HICLE THEFT SECURITY/VTSS INDICATOR -
DESCRIPTION).
Certain functions and features of the VTSS rely
upon resources shared with or controlled by other
modules in the vehicle over the Programmable Com-
munications Interface (PCI) data bus network. The
other modules that may affect VTSS operation are:
²Driver Door Module (Refer to 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/DOOR MOD-
ULE - DESCRIPTION).
²Passenger Door Module (Refer to 8 - ELECTRI-
CAL/ELECTRONIC CONTROL MODULES/DOOR
MODULE - DESCRIPTION).
DESCRIPTION - SENTRY KEY IMMOBILIZER
SYSTEM
Vehicles equipped with the Sentry Key Immobilizer
System (SKIS) can be identified by the presence of
an amber SKIS indicator in the instrument cluster
that will illuminate for about three seconds each
time the ignition switch is turned to the On position,
or by a gray molded rubber cap on the head of the
ignition key. Models not equipped with SKIS still
have a SKIS indicator in the cluster, but it will not
illuminate. Also, models not equipped with the SKIS
have a black molded rubber cap on the head of the
ignition key.
The SKIS includes the following major components,
which are described in further detail elsewhere in
this service manual:²Powertrain Control Module
²Sentry Key Immobilizer Module
²Sentry Key Transponder
²SKIS Indicator
Except for the Sentry Key transponders, which rely
upon Radio Frequency (RF) communication, hard
wired circuitry connects the SKIS components to the
electrical system of the vehicle.Refer to the appropri-
ate wiring information.
OPERATION
OPERATION - VEHICLE THEFT SECURITY
SYSTEM
The Vehicle Theft Security System (VTSS) is
divided into two basic subsystems: Vehicle Theft
Alarm (VTA) and Sentry Key Immobilizer System
(SKIS). The following are paragraphs that briefly
describe the operation of each of those two sub-
systems.
A Body Control Module (BCM) is used to control
and integrate many of the functions and features
included in the Vehicle Theft Security System
(VTSS). In the VTSS, the BCM receives inputs indi-
cating the status of the door ajar switches, the driver
cylinder lock switch, the ignition switch, the liftgate
ajar switches, the liftgate flip-up glass ajar switch,
the power lock switches and, in vehicles so equipped,
the hood ajar switch. The programming in the BCM
allows it to process the information from all of these
inputs and send control outputs to energize or de-en-
ergize the combination flasher, the horn relay (except
vehicles with the premium version of the VTA), and
the VTSS indicator. In addition, in vehicles built for
certain markets where premium versions of the VTA
is required, the BCM also exchanges messages with
the Intrusion Transceiver Module (ITM) over the Pro-
grammable Communications Interface (PCI) data
buss network to provide the features found in this
version of the VTA. The control of these inputs and
outputs are what constitute all of the features of the
VTSS. Following is information on the operation of
each of the VTSS features.
ENABLING
The BCM must have the VTSS function enabled in
order for the VTSS to perform as designed. The logic
in the BCM keeps its VTSS function dormant until it
is enabled using a DRBIIItscan tool. Refer to the
appropriate diagnostic information.
PRE-ARMING
The VTA has a pre-arming sequence. Pre-arming
occurs when a door, the tailgate, or the flip-up glass
is open when the vehicle is locked using a power lock
8Q - 2 VEHICLE THEFT SECURITYWJ
VEHICLE THEFT SECURITY (Continued)