wheel MERCEDES-BENZ SPRINTER 2006 Service Manual

remains illuminated until the cluster receives a
lamp-off message from the ECM, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The ECM continually monitors the constant engine
speed (ADR) switch and electronic messages from the
Controller Antilock Brake (CAB) concerning the sta-
tus of the four wheel speed sensors, the park brake
switch and the brake lamp switch to determine the
correct operating mode for the ADR feature. The
ECM then sends the proper lamp-on or lamp-off mes-
sages to the instrument cluster. See the owner's man-
ual in the vehicle glove box for more information on
the features, use, activation and deactivation of the
constant engine speed (ADR) feature. For proper
diagnosis of the ADR feature, the ECM, the CAB, the
CAN data bus, or the electronic message inputs to
the instrument cluster that control the ADR indica-
tor, a diagnostic scan tool is required. Refer to the
appropriate diagnostic information.
AIRBAG INDICATOR
DESCRIPTION
An airbag indicator is standard equipment on all
instrument clusters. The airbag indicator is located
near the left edge of the instrument cluster, next to
the tachometer. The airbag indicator consists of a
stencil-like cutout of the letters ªSRSº 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. A red
Light Emitting Diode (LED) behind the cutout in the
opaque layer of the overlay causes the ªSRSº text to
appear in red through the translucent outer layer of
the overlay when the indicator is illuminated from
behind by the LED, which is soldered onto the
instrument cluster electronic circuit board. The air-
bag indicator is serviced as a unit with the instru-
ment cluster.
OPERATION
The airbag (SRS) indicator gives an indication to
the vehicle operator when the Airbag Control Module
(ACM) has recorded a Diagnostic Trouble Code (DTC)
for a Supplemental Restraint System (SRS) circuit or
component malfunction. Such a DTC may indicate
that the SRS is faulty or inoperative. The airbag
indicator is controlled by a transistor on the instru-
ment cluster circuit board based upon cluster pro-
gramming and a hard wired input received by the
cluster from the ACM. The airbag 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 instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be offwhen the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the airbag indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the airbag indicator is illu-
minated for about four seconds. The entire four sec-
ond bulb test is a function of the ACM.
²Airbag Lamp-On Input- Each time the cluster
receives a lamp-on input from the ACM, the airbag
indicator will be illuminated. The indicator can be
flashed on and off, or illuminated solid, as dictated
by the ACM input. For some DTC's, if the problem
does not recur, the ACM will send a lamp-off input
automatically. Other DTC's may require that a fault
be repaired and the ACM be reset before a lamp-off
input will be sent. For more information on the ACM
and the DTC set and reset parameters, refer to 8 -
ELECTRICAL/RESTRAINTS/AIRBAG CONTROL
MODULE - OPERATION). The indicator remains
illuminated until the cluster receives a lamp-off
input from the ACM, or until the ignition switch is
turned to the Off position, whichever occurs first.
²Airbag Indicator Malfunction- Following the
seatbelt reminder function, each time the cluster
detects a malfunction in the airbag (SRS) indicator or
the airbag indicator circuit, the cluster will flash the
seatbelt indicator on and off. The cluster will con-
tinue to flash the seatbelt indicator until the airbag
indicator circuit fault is resolved, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The ACM continually monitors the SRS circuits
and sensors to decide whether the system is in good
operating condition. The ACM then provides the
proper lamp-on or lamp-off inputs to the instrument
cluster. If the ACM provides a lamp-on input after
the bulb test, it indicates that the ACM has detected
a system malfunction and/or that the airbags and
seat belt tensioners may not deploy when required,
or may deploy when not required. The ACM will
store a DTC for any malfunction it detects. The ACM
input circuit to the instrument cluster can be diag-
nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the SRS, the ACM, or
the instrument cluster circuitry that controls the air-
bag indicator, a diagnostic scan tool is required. Refer
to the appropriate diagnostic information.
AMBIENT TEMPERATURE
INDICATOR
DESCRIPTION
An ambient temperature indicator is optional
equipment on all instrument clusters. In vehicles so
VAINSTRUMENT CLUSTER 8J - 11

(EBV) system. This indicator is controlled by a tran-
sistor on the instrument cluster circuit board based
upon cluster programming, electronic messages
received by the cluster from the Controller Antilock
Brake (CAB) over the Controller Area Network
(CAN) data bus, and a hard wired input from the
brake fluid level switch. The brake 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 instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the brake indica-
tor for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the brake indicator is illu-
minated by the instrument cluster for about two sec-
onds as a bulb test.
²Brake Fluid Level Switch Input- Each time
the cluster detects ground on the brake indicator sig-
nal circuit (brake fluid level switch closed = brake
fluid level low) while the ignition switch is in the On
position, the brake indicator is illuminated. The indi-
cator remains illuminated until the brake signal indi-
cator input to the cluster is an open circuit (brake
fluid level switch open = brake fluid level okay), or
until the ignition switch is turned to the Off position,
whichever occurs first.
²Electronic Brake Force Distribution (EBV)
Indicator Lamp-On Message- Each time the clus-
ter receives a EBV indicator lamp-on message from
the CAB, the indicator will be illuminated. The indi-
cator remains illuminated until the cluster receives a
lamp-off message from the CAB, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The CAB continually monitors the EBV system cir-
cuits and sensors to decide whether the system is in
good operating condition. The CAB then sends the
proper lamp-on or lamp-off messages to the instru-
ment cluster. If the CAB sends a lamp-on message
after the bulb test, it indicates that the CAB has
detected a system malfunction and that the EBV sys-
tem has become inoperative. The CAB will store a
Diagnostic Trouble Code (DTC) for any malfunction it
detects.
The brake fluid level switch in the brake master
cylinder provides a hard wired ground input to the
instrument cluster circuitry through the brake indi-
cator signal circuit whenever the fluid level in the
brake master cylinder is low. The switch is connected
in parallel between ground and the instrument clus-
ter. The brake fluid level switch and the input circuit
to the instrument cluster can be diagnosed using con-
ventional diagnostic tools and methods. For properdiagnosis of the instrument cluster circuitry that con-
trols the brake indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
BRAKE WEAR INDICATOR
DESCRIPTION
A brake wear indicator is standard equipment on
all instrument clusters. The brake wear indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
brake wear indicator consists of the International
Control and Display Symbol icon for ªWorn Brake
Liningsº imprinted within a rectangular 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.
An amber Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against an amber field
through the translucent outer layer of the overlay
when the indicator is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. The brake wear indicator is
serviced as a unit with the instrument cluster.
OPERATION
The brake wear indicator gives an indication to the
vehicle operator when the brake linings have reached
their wear limits. This indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and a hard wired
input from the four brake wear sensors, one at each
wheel. The brake wear indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the brake wear indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the brake wear indicator is
illuminated by the instrument cluster for about two
seconds as a bulb test.
²Brake Wear Sensor Input- Each time the
cluster detects ground on the brake wear sense cir-
cuit (brake wear sensor closed = brake lining wear
limit exceeded) while the ignition switch is in the On
position, the brake wear indicator is illuminated. The
indicator remains illuminated until the brake wear
sense input to the cluster is an open circuit (brake
wear sensor open = brake lining wear within limits),
VAINSTRUMENT CLUSTER 8J - 13

or until the ignition switch is turned to the Off posi-
tion, whichever occurs first.
A brake wear sensor located at each wheel provides
a hard wired ground input to the instrument cluster
circuitry through the brake wear sense circuit when-
ever the brake linings for that wheel have exceeded
their wear limits. The four normally open brake wear
sensors are connected in parallel between ground and
instrument cluster. The brake wear sensors and their
input circuit to the instrument cluster can be diag-
nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the instrument cluster
circuitry that controls the brake wear indicator, a
diagnostic scan tool is required. Refer to the appro-
priate diagnostic information.
CHARGING INDICATOR
DESCRIPTION
A charging indicator is standard equipment on all
instrument clusters. The charging indicator is located
near the lower edge of the instrument cluster, to the
left of the multi-function indicator display. The
charging indicator consists of the International Con-
trol and Display Symbol icon for ªBattery Charging
Conditionº imprinted within a rectangular 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. A red Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against a red field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The charging indicator is ser-
viced as a unit with the instrument cluster.
OPERATION
The charging indicator gives an indication to the
vehicle operator when the electrical system voltage is
too low. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and a hard wired input from the
generator. The charging indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the charging indica-
tor for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position with the engine not run-ning the charging indicator is illuminated by the
instrument cluster as a bulb test.
²Generator Input- Each time the cluster
detects that the voltage of the generator input is 12.7
volts or lower while the engine is running, the charg-
ing indicator will be illuminated. The indicator
remains illuminated until the cluster detects that the
voltage of the generator input is above 12.7 volts, or
until the ignition switch is turned to the Off position,
whichever occurs first.
The generator provides a hard wired input to the
instrument cluster circuitry on the engine running
(D+) circuit. If the instrument cluster turns on the
indicator while the engine is running, it may indicate
that the charging system requires service. The gener-
ator input circuit to the instrument cluster can be
diagnosed using conventional diagnostic tools and
methods. For proper diagnosis of the charging sys-
tem, or the instrument cluster circuitry that controls
the charging indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
CLOCK
DESCRIPTION
An electronic digital clock is standard equipment
on all instrument clusters. In vehicles equipped with
the optional ambient temperature indicator, the clock
indication can be toggled with the ambient tempera-
ture indication on the right side of the multi-function
indicator Liquid Crystal Display (LCD) located near
the lower edge of the instrument cluster, directly
below the speedometer. The clock provides a 12 hour-
based, digital indication of the current hours and
minutes. The indications of the clock are not visible
when the LCD is not illuminated. When illuminated
the indications appear as dark characters silhouetted
against an amber field. When the exterior lighting is
turned Off, the display is illuminated at maximum
brightness. When the exterior lighting is turned On
the display illumination level can be adjusted in con-
cert with the cluster general illumination lighting
using the ª+º (plus) and ª2º (minus) multi-function
indicator push buttons. The clock is serviced as a
unit with the instrument cluster.
OPERATION
The clock gives an indication to the vehicle opera-
tor of the current time. The electronic digital clock is
controlled by the instrument cluster microprocessor
based upon cluster programming. The clock display is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indication
to be viewed when the multi-function indicator Liq-
uid Crystal Display (LCD) is activated. However, the
8J - 14 INSTRUMENT CLUSTERVA

the instrument cluster, directly below the speedome-
ter. However, the odometer and trip odometer infor-
mation are not displayed simultaneously. The ªmiº
(miles) or ªkmº (kilometers) switch on the instrument
cluster circuit board toggles the display between
odometer and trip odometer modes by depressing the
switch push button that extends through the lower
edge of the cluster lens, directly below the multi-
function indicator LCD.
The odometer and trip odometer information is
stored in the instrument cluster memory. This infor-
mation can be increased when the proper inputs are
provided to the instrument cluster, but the informa-
tion cannot be decreased. The odometer can display
values up to 999,999 kilometers (999,999 miles). The
odometer latches at these values, and will not roll
over to zero. The trip odometer can display values up
to 999.9 kilometers (999.9 miles) before it rolls over
to zero. The odometer display does not have a deci-
mal point and will not show values less than a full
unit (kilometer or mile), while the trip odometer dis-
play does have a decimal point and will show tenths
of a unit (kilometer or mile). The unit of measure
(kilometers or miles) for the odometer and trip odom-
eter display is imprinted on the cluster overlay below
the left end of the LCD. The unit of measure for the
instrument cluster odometer/trip odometer is selected
at the time that it is manufactured, and cannot be
changed.
The indications of the odometer/trip odometer are
not visible when the LCD is not illuminated. When
illuminated the indications appear as dark charac-
ters silhouetted against an amber field. When the
exterior lighting is turned Off, the display is illumi-
nated at maximum brightness. When the exterior
lighting is turned On the display illumination level
can be adjusted in concert with the cluster general
illumination lighting using the plus and minus multi-
function indicator push buttons. The odometer has a
ªRental Carº mode, which will activate the multi-
function indicator LCD and illuminate the odometer
information for about thirty seconds after one of the
multi-function indicator push buttons is momentarily
depressed, or after the key is inserted into the igni-
tion switch lock cylinder with the ignition switch in
the Off position.
The odometer/trip odometer and the miles/kilome-
ters switch, and the miles/kilometers switch push
button are serviced as a unit with the instrument
cluster.
OPERATION
The odometer and trip odometer give an indication
to the vehicle operator of the distance the vehicle has
traveled. This indicator is controlled by the instru-
ment cluster circuitry based upon cluster program-
ming and electronic messages received by the cluster
from the Controller Anti-lock Brake (CAB) over theController Area Network (CAN) data bus. The odom-
eter and trip odometer information is displayed by
the multi-function indicator Liquid Crystal Display
(LCD). The LCD will display the odometer informa-
tion whenever it is activated, and will display the
last previously selected odometer or trip odometer
information when the ignition switch is turned to the
On position. The instrument cluster circuitry controls
the LCD and provides the following features:
²Odometer/Trip Odometer Display Toggling-
Actuating the multi-function indicator ªmiº (miles) or
ªkmº (kilometers) switch push button momentarily
with the LCD illuminated will toggle the display
between the odometer and trip odometer information.
Each time the LCD is illuminated with the ignition
switch in the On or Start positions, the display will
automatically return to the last mode previously
selected (odometer or trip odometer).
²Trip Odometer Reset- When the multi-func-
tion indicator ªmiº (miles) or ªkmº (kilometers) switch
push button is pressed and held for longer than
about two seconds, the trip odometer will be reset to
000.0 kilometers (miles). The LCD must be display-
ing the trip odometer information in order for the
trip odometer information to be reset.
The CAB continually monitors the vehicle speed
pulse information received from the four wheel speed
sensors, then sends the proper distance messages to
the instrument cluster. For proper diagnosis of the
wheel speed sensors, the CAB, the CAN data bus, or
the electronic message inputs to the instrument clus-
ter that control the odometer/trip odometer, a diag-
nostic scan tool is required. Refer to the appropriate
diagnostic information.
PARK BRAKE INDICATOR
DESCRIPTION
A park brake indicator is standard equipment on
all instrument clusters. The park brake indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
park brake indicator consists of stencil-like cutout of
the word ªPARKº 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. A red Light Emitting
Diode (LED) behind the cutout in the opaque layer of
the overlay causes the ªPARKº text to appear in red
through the translucent outer layer of the overlay
when the indicator is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. The park brake indicator is
serviced as a unit with the instrument cluster.
VAINSTRUMENT CLUSTER 8J - 23

connected in series between the instrument cluster
and ground. The seat belt switch and the seatbelt
indicator driver circuit to the instrument cluster can
be diagnosed using conventional diagnostic tools and
methods. For proper diagnosis of the ACM, the air-
bag (SRS) indicator, or the instrument cluster cir-
cuitry that controls the seatbelt indicator, a
diagnostic scan tool is required. Refer to the appro-
priate diagnostic information.
SPEEDOMETER
DESCRIPTION
A speedometer is standard equipment on all instru-
ment clusters. The speedometer is located in the cen-
ter of the instrument cluster. The speedometer
consists of a movable gauge needle or pointer con-
trolled by the instrument cluster circuitry and a fixed
210 degree primary outer scale on the gauge dial face
that reads left-to-right either from ª0º to ª100º miles-
per-hour, or from ª0º to ª180º kilometers-per-hour,
depending upon the market for which the vehicle is
manufactured. Each version also has a secondary
inner scale on the gauge dial face that provides the
equivalent opposite units from the primary scale.
Text appearing on the cluster overlay near the left
end of each scale abbreviates the unit of measure,
either ªmphº or ªkm/hº.
The speedometer graphics are white against a
black field, making them clearly visible within the
instrument cluster in daylight. When illuminated
from behind by the panel lamps dimmer controlled
cluster illumination lighting with the exterior lamps
turned On, the white graphics appear amber. The
orange gauge needle is internally illuminated. Gauge
illumination is provided by Light Emitting Diode
(LED) units soldered onto the instrument cluster
electronic circuit board. The speedometer is serviced
as a unit with the instrument cluster.
OPERATION
The speedometer gives an indication to the vehicle
operator of the vehicle road speed. This gauge is con-
trolled by the instrument cluster circuit board based
upon cluster programming and electronic messages
received by the cluster from the Controller Anti-lock
Brake (CAB) over the Controller Area Network
(CAN) data bus. The speedometer is an air core mag-
netic unit that receives battery current on the instru-
ment cluster electronic circuit board when the
instrument cluster detects that the ignition switch is
in the On position. 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:²Vehicle Speed Message- Each time the clus-
ter receives a vehicle speed message from the CAB it
will calculate the correct vehicle speed reading and
position the gauge needle at that relative speed posi-
tion on the gauge scale. The gauge needle will con-
tinue to be positioned at the actual vehicle speed
position on the gauge scale until the ignition switch
is turned to the Off position.
²Communication Error- If the cluster fails to
receive a speedometer message, it will hold the gauge
needle at the last indication for about three seconds,
or until the ignition switch is turned to the Off posi-
tion, whichever occurs first. After three seconds, the
gauge needle will return to the left end of the gauge
scale.
The CAB continually monitors the four wheel
speed sensors to determine the vehicle road speed.
The CAB then sends the proper vehicle speed mes-
sages to the instrument cluster. For proper diagnosis
of the wheel speed sensors, the CAB, the CAN data
bus, or the electronic message inputs to the instru-
ment cluster that control the speedometer, a diagnos-
tic scan tool is required. Refer to the appropriate
diagnostic information.
TACHOMETER
DESCRIPTION
A tachometer is standard equipment on all instru-
ment clusters. The tachometer is located to the left of
the speedometer, to the left of center in the instru-
ment cluster. The tachometer consists of a movable
gauge needle or pointer controlled by the instrument
cluster circuitry and a fixed 45 degree scale on the
gauge dial face that reads left-to-right from ª0º to ª7º.
The text ªrpm X 1000º imprinted on the cluster over-
lay near the left end of the gauge scale identifies that
each number on the tachometer scale is to be multi-
plied by 1000 rpm.
The tachometer graphics are white against a black
field, making them clearly visible within the instru-
ment cluster in daylight. When illuminated from
behind by the panel lamps dimmer controlled cluster
illumination lighting with the exterior lamps turned
On, the white graphics appear amber. The orange
gauge needle is internally illuminated. Gauge illumi-
nation is provided by Light Emitting Diode (LED)
units soldered onto the instrument cluster electronic
circuit board. The tachometer is serviced as a unit
with the instrument cluster.
OPERATION
The tachometer gives an indication to the vehicle
operator of the engine speed. This gauge is controlled
by the instrument cluster circuit board based upon
cluster programming and electronic messages
VAINSTRUMENT CLUSTER 8J - 25

received by the cluster from the Engine Control Mod-
ule (ECM) over the Controller Area Network (CAN)
data bus. The tachometer is an air core magnetic
unit that receives battery current on the instrument
cluster electronic circuit board when the instrument
cluster detects that the ignition switch is in the On
position. 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 nee-
dle position and provides the following features:
²Engine Speed Message- Each time the cluster
receives an engine speed message from the ECM it
will calculate the correct engine speed reading and
position the gauge needle at that relative speed posi-
tion on the gauge scale. The gauge needle will con-
tinually be repositioned at the relative engine speed
position on the gauge scale until the engine stops
running, or until the ignition switch is turned to the
Off position, whichever occurs first.
²Communication Error- If the cluster fails to
receive an engine speed message, it will hold the
gauge needle at the last indication for about three
seconds, or until the ignition switch is turned to the
Off position, whichever occurs first. After three sec-
onds, the gauge needle will return to the left end of
the gauge scale.
The ECM continually monitors the crankshaft posi-
tion sensor to determine the engine speed. The ECM
then sends the proper engine speed messages to the
instrument cluster. For proper diagnosis of the
crankshaft position sensor, the ECM, the CAN data
bus, or the electronic message inputs to the instru-
ment cluster that control the tachometer, a diagnos-
tic scan tool is required. Refer to the appropriate
diagnostic information.
TRACTION CONTROL INDICA-
TOR
DESCRIPTION
A traction control (ASR) indicator is standard
equipment on all instrument clusters. The traction
control indicator is located near the center of the
speedometer in the instrument cluster. The traction
control indicator consists of an ª!º (exclamation point)
imprinted within a triangular 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. An
amber Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the excla-
mation point to appear silhouetted against an amber
field through the translucent outer layer of the over-
lay when the indicator is illuminated from behind by
the LED, which is soldered onto the instrument clus-ter electronic circuit board. The traction control indi-
cator is serviced as a unit with the instrument
cluster.
OPERATION
The traction control (ASR) indicator gives several
indications to the vehicle operator concerning the
operating status of the traction control (ASR) system.
The traction control indicator is controlled by a tran-
sistor on the instrument cluster circuit board based
upon cluster programming and electronic messages
received by the cluster from the Controller Anti-lock
Brake (CAB) over the Controller Area Network
(CAN) data bus. The traction control 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 instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the traction con-
trol indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the traction control indica-
tor is illuminated for about two seconds as a bulb
test.
²Traction Control (ASR) Indicator Lamp-On
Message- Each time the cluster receives a traction
control indicator lamp-on message from the CAB, the
indicator will be illuminated. This indicator can be
flashed on and off, or illuminated solid, as dictated
by the CAB message. The indicator is illuminated
solid when the traction control system has been deac-
tivated; and is flashed when the traction control is
activated or when the driven wheels lose traction
with the traction control deactivated. The indicator
remains flashing or illuminated solid until the clus-
ter receives a lamp-off message from the CAB, or
until the ignition switch is turned to the Off position,
whichever occurs first.
The CAB continually monitors the traction control
(ASR) switch and the four wheel speed sensors to
determine the correct operating mode for the traction
control system. The CAB then sends the proper
lamp-on or lamp-off messages to the instrument clus-
ter. See the owner's manual in the vehicle glove box
for more information on the features, use, activation
and deactivation of the traction control (ASR) system.
For proper diagnosis of the traction control system,
the CAB, the CAN data bus, or the electronic mes-
sage inputs to the instrument cluster that control the
traction control indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
8J - 26 INSTRUMENT CLUSTERVA

REAR TURN LAMP BULB
REMOVAL.............................23
INSTALLATION.........................23
REPEATER LAMP BULB
REMOVAL.............................23
INSTALLATION.........................24
REPEATER LAMP UNIT
REMOVAL.............................24INSTALLATION.........................25
TAIL LAMP UNIT
REMOVAL.............................25
INSTALLATION.........................26
TURN SIGNAL RELAY
REMOVAL.............................26
INSTALLATION.........................26
LAMPS / LIGHTING - EXTE-
RIOR
DESCRIPTION
The exterior lighting system for this model
includes the following exterior lamps:
²Backup Lamps- The backup (or reverse) lamps
are integral to the tail lamp units mounted to the
back of the quarter panel on each side of the tailgate
at the rear of the vehicle.
²Brake Lamps- The brake (or stop) lamps
include a bulb and reflector that are integral to the
tail lamp units mounted to the back of the quarter
panel on each side of the tailgate opening, and the
Center High Mounted Stop Lamp (CHMSL) that is
centered on the rear edge of the roof panel above the
tailgate opening.
²Daytime Running Lamps- Vehicles manufac-
tured for sale in Canada have a Daytime Running
Lamps (DRL) relay that illuminates the low beam
headlamp bulbs whenever the engine is running.
²Fog Lamps- Fog lamp bulbs and reflectors are
included in both front lamp units of vehicles
equipped with this option.
²Hazard Warning Lamps- The hazard warning
lamps include all of the right and left turn signal and
repeater lamps.
²Headlamps- Separate low beam and high
beam headlamp bulbs are installed in the front lamp
unit on each side of the front grille opening. A head-
lamp leveling actuator motor is also integral to each
front lamp unit.
²Park Lamps- The park lamps include the front
park/side marker lamps and front position lamps
that are integral to the front lamp units mounted on
either side of the front grille opening, as well as the
rear park lamps and rear side marker lamps that are
integral to the tail lamp units mounted to the back of
the quarter panel on each side of the tailgate open-
ing. Included in the park lamps circuit are two rear
license plate lamp units mounted on the left rear
tailgate door. The park lamps may also include
optional clearance lamps, which are located on each
side of a vehicle that is so equipped.
²Turn Signal Lamps- The turn signal lamps
include the front turn lamps that are integral to the
front lamp units, the rear turn lamps that are inte-
gral to the tail lamp units, and a repeater lampmounted to each front fender just above the front
wheel opening.
Other components of the exterior lighting system
for this model include:
²Brake Lamp Switch- A plunger-type brake
lamp switch is located on the steering column sup-
port bracket under the instrument panel and actu-
ated by the brake pedal arm.
²Daytime Running Lamp Relays- Vehicles
manufactured for sale in Canada have two Daytime
Running Lamps (DRL) relays. Dedicated right and
left side relays illuminate the low beam headlamp
bulb installed in each front lamp unit whenever the
engine is running. These relays are located in dedi-
cated vehicle wire harness connectors within the
driver side front seat riser.
²Fog Lamp Relay- Vehicles equipped with the
optional fog lamps have a fog lamp relay located in a
dedicated vehicle wire harness connector within the
driver side front seat riser.
²Fog Lamp Switch- A fog lamp switch is
mounted in the instrument cluster bezel, below the
cluster and outboard of the steering column on vehi-
cles equipped with this option.
²Headlamp Leveling Motor- A headlamp lev-
eling actuator motor is located on the back of each
headlamp housing and adjusts both the low beam
headlamp, high beam headlamp, and fog lamp (if
equipped) reflector frames in unison.
²Headlamp Leveling Switch- A thumbwheel
actuated headlamp leveling switch is mounted in the
instrument cluster bezel, below the cluster and out-
board of the steering column.
²Multi-Function Switch- The multi-function
switch is located on the top of the steering column,
just below the steering wheel. The multi-function
switch is connected directly to the fuse block located
below the steering column through an integral inter-
face connector. Only the left (lighting), right (wiper)
control stalks and the hazard warning switch button
for the multi-function switch are visible, the remain-
der of the switch is concealed beneath the steering
column shrouds. The multi-function switch includes a
left (lighting) control stalk and a right (wiper) control
stalk. The left control stalk is dedicated to providing
almost all of the driver controls for the exterior light-
ing system.
²Trailer Tow Connector- Vehicles equipped
with a factory-approved, field-installed trailer towing
8L - 2 LAMPS/LIGHTING - EXTERIORVA

seat riser, a fog lamp switch installed in the cluster
bezel on the instrument panel outboard of the steer-
ing column, and a fog lamp bulb installed in each of
the two front lamp units. The front fog lamps have a
path to ground at all times through their connection
to the vehicle wire harness. The headlamp switch cir-
cuitry of the left (lighting) control stalk of the multi-
function switch controls front fog lamp operation by
providing battery current to the front fog lamp relay
only when the low beam headlamps are selected. The
fog lamp switch controls front fog lamp operation by
energizing or de-energizing the front fog lamp relay
control coil.
HAZARD WARNING LAMPS
With the hazard switch in the On position, the
hazard switch button illuminates and the right and
left turn signal indicators as well as the right and
left turn signal lamps begin to flash on and off. When
the hazard warning system is activated, the hazard
switch circuitry within the multi-function switch and
the wipers, turn signals and engine start control
module electronic circuitry within the fuse block will
repeatedly energize and de-energize the turn signal
relay located in the fuse block. The turn signal relay
switches battery current from a fused B(+) fuse in
the fuse block to the turn signal indicators and the
turn signal lamps. The flashing of the hazard switch
button illumination lamp is also controlled by the
output from the turn signal relay.
HEADLAMPS
The headlamp system includes the exterior lighting
switches integral to the left (lighting) control stalk of
the multi-function switch as well as the low and high
beam bulbs installed in the right and left front lamp
units (Fig. 1). The headlamp bulbs have a path to
ground at all times through the vehicle wire harness.
The exterior lighting switches control headlamp oper-
ation by providing battery current to the selected low
or high beam bulbs. Each front lamp unit includes
two integral adjustment screws to be used for static
horizontal and vertical aiming of the headlamp beam
reflectors.HEADLAMP LEVELING
The headlamp leveling system includes a leveling
actuator motor integral to each front lamp unit, and
a rotary thumbwheel actuated headlamp leveling
switch in the cluster bezel on the instrument panel
outboard of the steering column. The headlamp lev-
eling system allows the headlamp beam reflectors to
be adjusted to one of four vertical positions to com-
pensate for changes in inclination caused by the load-
ing of the vehicle suspension. The actuator motors
are mechanically connected through an integral
pushrod to an adjustable headlamp reflector. The
headlamp leveling switch is a resistor multiplexed
unit that provides one of four voltage outputs to the
headlamp leveling motors. The headlamp leveling
motors will move the headlamps to the selected posi-
tion based upon the voltage input received from the
switch. The headlamp leveling motors and switch
have a path to ground at all times. The headlamp
leveling components operate on battery current
received through the park lamps circuit so that the
system will only operate when the exterior lighting is
turned on.
PARK LAMPS
The park lamps system includes the exterior light-
ing switches integral to the left (lighting) control
stalk of the multi-function switch (Fig. 1), the front
park/side marker lamps, the front position lamps, the
rear park lamps, the rear side marker lamps, the
optional clearance lamps, and the license plate
lamps. Each of these lamps are provided with a path
to ground at all times through the vehicle wire har-
ness. The exterior lighting switches control the park
lamp operation by providing battery current through
the park lamps circuit to the appropriate lamp bulbs.
Fig. 1 Lighting Switch
1 - LEFT TURN SIGNAL
2 - RIGHT TURN SIGNAL
3 -EXTERIOR LIGHTING
4 - BEAM SELECT (DIMMER)
5 - OPTICAL HORN
8L - 4 LAMPS/LIGHTING - EXTERIORVA

TURN SIGNAL LAMPS
When the left (lighting) control stalk of the multi-
function switch is activated (Fig. 1), the turn signal
system illuminates the selected right or left turn sig-
nal indicator and the turn signal lamps begin to
flash. The turn signal lamps include a bulb integral
to each front lamp unit and each tail lamp unit, as
well as a repeater lamp bulb located on each front
fender above the front wheels. When the turn signal
system is activated, the turn signal switch circuitry
within the multi-function switch and the electronic
circuitry of the wipers, turn signals and engine start
control module within the fuse block will repeatedly
energize and de-energize the turn signal relay
located in the fuse block. The turn signal relay
switches battery current from a fused ignition switch
output fuse in the fuse block to the appropriate turn
signal indicator and turn signal lamps.
The ElectroMechanical Instrument Cluster (EMIC)
contactless relay will generate repetitive, audible
turn signal ªclickº sounds to emulate the sounds of a
conventional electro-mechanical turn signal flasher
at one of two rates to coincide with the flashing of
the turn signals. The slow rate emulates normal turn
signal operation, while the fast rate emulates ªbulb
outº turn signal operation.
SPECIFICATIONS - LAMPS / LIGHTING - EXTE-
RIOR
BULB SPECIFICATIONS
LAMP BULB
Backup P21W - 12V 21W
Brake & Rear Park P21/5W - 12V 21/5W
Center High Mounted
StopP21W - 12V 21W
Clearance W3W - 12V 3W
Front Fog H1 - 12V 55W
Front Position W5W - 12V 5W
Front Turn, Park & Side
Marker3457 NA - 12V 28/7.5W
Amber Glass
Low Beam Headlamp H7 - 12V 55W
High Beam Headlamp H1 - 12V 55W
License Plate C5W - 12V 5W
Rear Side Marker R5W - 12V 5W
Rear Turn P21W - 12V 21W
Side Repeater W5W - 12V 3W
BACKUP LAMP BULB
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) If the vehicle is so equipped, remove the trim
from the inside of the right or left rear corner pillar.
(3) From inside the vehicle, use hand pressure to
push the two latch tabs toward the center of the tail
lamp unit socket plate and pull the socket plate
straight out from the inner rear pillar (Fig. 2).
(4) Pull the socket plate away from the inner rear
pillar far enough to access the backup lamp bulb
(Fig. 3).
Fig. 2 Tail Lamp Socket Plate Remove/Install
1 - SOCKET PLATE
2 - INNER REAR PILLAR
3 - LATCH TAB (2)
VALAMPS/LIGHTING - EXTERIOR 8L - 5

(5) Remove the backup lamp bulb from the tail
lamp socket plate.
INSTALLATION
(1) Install the backup lamp bulb into the tail lamp
socket plate (Fig. 3).
(2) Align the socket plate with the mounting hole
in the inner rear pillar.
(3) Using hand pressure, push the socket plate
gently and evenly into the inner rear pillar mounting
hole until both latch tabs are fully engaged (Fig. 2).
(4) If the vehicle is so equipped, reinstall the trim
onto the inside of the right or left rear corner pillar.
(5) Reconnect the battery negative cable.
BRAKE LAMP SWITCH
REMOVAL
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, or instrument panel component diagno-
sis or service. Disconnect and isolate the battery
negative (ground) cable, then wait two minutes for
the system capacitor to discharge before perform-
ing further diagnosis or service. This is the only
sure way to disable the supplemental restraint sys-
tem. Failure to take the proper precautions could
result in accidental airbag deployment.
(1) Disconnect and isolate the battery negative
cable.
(2) Locate the brake lamp switch on the pedal
bracket underneath the instrument panel (Fig. 4).(3) Depress the locking tab on the brake lamp
switch body behind the pedal bracket and rotate the
switch counterclockwise about 30 degrees (Fig. 5).
(4) Pull the switch forward in the vehicle far
enough to disengage the switch plunger from the
mounting hole in the pedal bracket.
(5) Disconnect the vehicle wire harness from the
brake lamp switch connector receptacle.
(6) Remove the brake lamp switch from the vehi-
cle.
Fig. 3 Tail Lamp Bulb Remove/Install
1 - BRAKE/PARK LAMP BULB
2 - BACKUP LAMP BULB
3 - TURN SIGNAL LAMP BULB
4 - SIDE MARKER LAMP BULB
5 - TAIL LAMP SOCKET PLATE
Fig. 4 Brake Lamp Switch Location
1 - PEDAL BRACKET
2 - BRAKE LAMP SWITCH
3 - BRAKE PEDAL
Fig. 5 Brake Lamp Switch Remove/Install
1 - PEDAL BRACKET
2 - PLUNGER
3 - BRAKE LAMP SWITCH
4 - CONNECTOR RECEPTACLE
5 - LOCKING TAB
8L - 6 LAMPS/LIGHTING - EXTERIORVA