Steer MERCEDES-BENZ SPRINTER 2006 Manual Online

HEATED SYSTEMS
TABLE OF CONTENTS
page page
HEATED GLASS........................... 1
HEATED MIRRORS......................... 9HEATED SEATS........................... 10
HEATED GLASS
TABLE OF CONTENTS
page page
HEATED GLASS
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING
ELECTRIC BACKLIGHT (EBL) SYSTEM.....2
REAR WINDOW DEFOGGER RELAY
DESCRIPTION..........................3
OPERATION............................3
REMOVAL.............................4
INSTALLATION..........................4REAR WINDOW DEFOGGER SWITCH
DESCRIPTION..........................4
OPERATION............................4
DIAGNOSIS AND TESTING
REAR WINDOW DEFOGGER SWITCH......5
REMOVAL.............................6
INSTALLATION..........................6
REAR WINDOW DEFOGGER GRID
STANDARD PROCEDURE
GRID LINE AND TERMINAL REPAIR........7
HEATED GLASS
DESCRIPTION
CAUTION: Grid lines can be damaged or scraped
off with sharp instruments. Care should be taken in
cleaning glass or removing foreign materials,
decals or stickers. Normal glass cleaning solvents
or hot water used with rags or toweling is recom-
mended.
The rear window defogger system, also known as
the electric backlight (EBL), consists of a backglass
with two vertical bus bars linked by a series of grid
lines fired onto the inside surface of the rear window.
The EBL system is turned On or Off by a control
switch (Fig. 1) located in the instrument panel near
the right side of the steering wheel, which sends a
request signal to the rear window defogger module
that operates the left and right rear window defogger
relays located in the fuse/relay block under the driv-
ers seat.
Circuit protection is provided by a 30 amp fuse
also located in the fuse/relay block.
OPERATION
When the rear window defogger switch is pressed
to the On position, current is directed through the
switch to the rear window defogger module. The rear
window defogger module then grounds the control
side of the left and right rear window defogger (EBL)
Fig. 1 Rear Window Defogger Switch
1 - REAR WINDOW DEFOGGER SWITCH
2 - INSTRUMENT PANEL
VAHEATED SYSTEMS 8G - 1

²The coil ground terminal (86) is hardwired to
ground point G202.
²The coil battery terminal (85) receives a battery
current input from the rear window defogger module
when the rear window defogger switch is energized.
²The normally open terminal (87) provides a bat-
tery current output to the rear window defogger grid
lines through the relay output circuit only when the
rear window defogger relay coil is energized.
²The normally closed terminal (87A) is not con-
nected to any circuit in this application, but provides
a battery current output only when the rear window
defogger relay coil is de-energized.
The left and right EBL relays cannot be repaired
and, if faulty or damaged, they must be replaced.
Refer to the appropriate wiring information for diag-
nosis and testing of the EBL relays and for complete
rear window defogger system wiring diagrams.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the cover from the fuse/relay block
(Fig. 4).
NOTE: Refer to the fuse and relay map located on
the inner surface of the fuse/relay block cover for
the left and right rear window defogger (EBL) relay
locations.
(3) Remove the EBL relays from the fuse/relay
block as required.
INSTALLATION
NOTE: Refer to the fuse and relay map located on
the inner surface of the fuse/relay block cover for
the left and right rear window defogger (EBL) relay
locations.
(1) Position the rear window defogger (EBL) relays
as required into their proper receptacles in the fuse/
relay block.
(2) Align the EBL relay terminals with the termi-
nal cavities in the fuse/relay block receptacles.
(3) Push down firmly on the EBL relays until the
terminals are fully seated in the terminal cavities in
the fuse/relay block receptacles.
(4) Install the cover onto the fuse/relay block.
(5) Reconnect the negative battery cable.
REAR WINDOW DEFOGGER
SWITCH
DESCRIPTION
The rear window defogger switch is mounted in the
instrument panel to the right of the steering wheel
(Fig. 5). The rear window defogger switch contains a
yellow indicator lamp that illuminates when the rear
window defogger (EBL) system is activated.
The rear window defogger switch and the defogger
switch indicator cannot be repaired and, if faulty or
damaged, the rear window defogger switch must be
replaced.
OPERATION
A yellow indicator lamp will illuminate when the
rear window defogger switch is activated. The switch
Fig. 4 Rear Window Defogger (EBL) Relays
1 - DRIVERS SEAT
2 - FUSE/RELAY BLOCKFig. 5 Rear Window Defogger Switch
1 - REAR WINDOW DEFOGGER SWITCH
2 - INSTRUMENT PANEL
8G - 4 HEATED GLASSVA

energizes the timing circuit of the rear window defog-
ger module which then activates the rear window
defogger (EBL) relays. The EBL relays controls the
current flow to the rear window defogger grids. The
EBL system will operate for approximately five min-
utes or until the rear window defogger switch or igni-
tion switch is turned off. Refer to 8 - ELECTRICAL/
HEATED GLASS - DIAGNOSIS AND TESTING for
diagnosis and testing of the rear window defogger
switch.
The rear window defogger switch cannot be
repaired and, if faulty or damaged, it must be
replaced.
DIAGNOSIS AND TESTING
REAR WINDOW DEFOGGER SWITCH
WARNING: On vehicles equipped with airbags, dis-
able the airbag system before attempting any steer-
ing wheel, steering column, or instrument panel
component diagnosis or service. Disconnect and
isolate the battery negative (ground) cable, then
wait two minutes for the airbag system capacitor to
discharge before performing further diagnosis or
service. This is the only sure way to disable the air-
bag system. Failure to take the proper precautions
could result in an accidental airbag deployment and
possible personal injury.
NOTE: The rear window defogger switch may be
tested in the vehicle or out of the vehicle, on a
bench.
NOTE: For circuit descriptions and diagrams of the
rear window defogger system, refer to 8W - WIRING
DIAGRAM INFORMATION.
(1) Remove the rear window defogger switch from
the instrument panel, but leave the switch connected
(Refer to 8 - ELECTRICAL/HEATED GLASS/REAR
WINDOW DEFOGGER SWITCH - REMOVAL).
(2) Turn the ignition switch ON.
(3) Using a voltmeter, check for battery voltage at
Pin 3 of the rear window defogger switch (Fig. 6).
(a) If OK, go to Step 4.
(b) If NOT OK, check fuse 7 (15 amp) in fuse
block #1. If fuse is OK, check the wiring circuits.
Refer to 8W - WIRING DIAGRAM INFORMA-
TION.
(4) Check Pin 7, with defogger switch in the On
position there should be battery voltage and, no volt-
age with the switch in the Off position.
(a) If OK, go to Step 5.(b) If NOT OK, no voltage in the On position or
voltage in the Off position, replace the rear window
defogger switch.
(5) Press the defogger switch to the On position.
The indicator lamp should come on and remain on
for approximately 5 minutes.
(a) If OK, install the rear window defogger
switch (Refer to 8 - ELECTRICAL/HEATED
GLASS/REAR WINDOW DEFOGGER SWITCH -
INSTALLATION).
(b) If NOT OK, go to Step 6.
(6) Check Pin 9, with defogger switch in the On
position there should be battery voltage.
(a) If OK, go to Step 7.
(b) If NOT OK, check the wiring circuits. Refer
to 8W - WIRING DIAGRAM INFORMATION.
(7) Check Pin 10 for a good ground.
(a) If OK, replace the rear window defogger
switch.
(b) If NOT OK, check the wiring circuits. Refer
to 8W - WIRING DIAGRAM INFORMATION.
Fig. 6 Rear Window Defogger Switch Connector
VAHEATED GLASS 8G - 5

DEFOGGER SWITCH CONNECTOR PIN
CALL-OUT
PIN FUNCTION
1 FUSED B+ (DRL RELAY)
3 IGNITION SWITCH OUTPUT (START-
RUN)
5 PANEL LAMPS DRIVER
7 DEFOGGER SWITCH OUTPUT
9 PANEL LAMPS DRIVER
10 GROUND
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 negative battery
cable.
(2) Remove the cluster bezel from the instrument
panel (Fig. 7) (Refer to 23 - BODY/INSTRUMENT
PANEL/CLUSTER BEZEL - REMOVAL).(3) From the back of the cluster bezel, squeeze the
two latches on the rear window defogger switch body
and push the switch out through the face of the bezel
(Fig. 8).
(4) Remove the rear window defogger switch from
the cluster bezel.
INSTALLATION
(1) Position the rear window defogger switch to the
proper mounting hole on the face of the cluster bezel.
(2) Using hand pressure, push the rear window
defogger switch firmly and evenly into the switch
Fig. 7 Cluster Bezel Remove/Install
1 - SCREWS (2)
2 - CLUSTER BEZEL
3 - REAR WINDOW DEFOGGER SWITCH
4 - DEFOGGER SWITCH CONNECTOR
5 - WIRE HARNESS CONNECTOR
6 - WIRE HARNESS CONNECTOR
Fig. 8 Headlamp Leveling Switch Remove/Install
1 - SWITCH
2 - LATCH (2)
3 - CLUSTER BEZEL
8G - 6 HEATED GLASSVA

INSTRUMENT CLUSTER
DESCRIPTION
The instrument cluster for this model is an Elec-
troMechanical Instrument Cluster (EMIC) that is
located above the steering column opening in the
instrument panel, directly in front of the driver (Fig.
1). The remainder of the EMIC, including the mounts
and the electrical connections, are concealed within
the instrument panel behind the cluster bezel and
beneath the instrument panel top cover for the clus-
ter. The instrument cluster includes analog gauges,
meters, indicators, and acoustic signal transmit-
ters.The EMIC module also incorporates a multi-func-
tion indicator that consists of a digital Liquid Crystal
Display (LCD) unit for displaying odometer/trip
odometer information, an electronic digital clock,
engine oil level information, automatic transmission
gear selector position (PRNDL), and certain diagnos-
tic information. The multi-function indicator also has
four push button switches, which provide the vehicle
operator with an interface to adjust certain inputs to
the instrument cluster and to select from multiple
display options. If the vehicle is equipped with the
appropriate options, the multi-function indicator also
provides an outside ambient temperature indicator
display and an Active Service SYStem (ASSYST)
engine oil maintenance indicator to display engine oil
level and maintenance reminders.
The EMIC gauges and indicators are visible
through a dedicated opening in the cluster bezel on
the instrument panel and are protected by a clear
plastic cluster lens (Fig. 2) that is secured by eight
integral latches to the molded black plastic cluster
hood. Four, black plastic multi-function indicator
switch push buttons protrude through dedicated
holes in a rectangular black plastic switch bezel that
is integral to the cluster lens and located near the
lower edge of the cluster directly below the multi-
function indicator LCD unit. The cluster hood serves
as a visor and shields the face of the cluster from
ambient light and reflections to reduce glare. The
cluster hood has eight integral latches that engage
eight integral latch tabs on the cluster rear cover,
sandwiching the cluster housing unit between the
hood and the rear cover. The cluster hood also has
two integral pivot loops molded into its underside
that engage two pairs of molded pivot hooks that are
integral to the top of the instrument panel base
structure. These pivots allow the cluster to be rolled
rearward to ease service access to the wire harness
connectors at the back of the cluster.
The rear of the cluster housing and the EMIC elec-
tronic circuitry are protected by the molded plastic
rear cover. A mounting ear at each upper corner of
the rear cover are used to secure the EMIC to the
molded plastic instrument panel base unit with two
screws. The rear cover includes clearance holes for
the two cluster connector receptacles on the cluster
electronic circuit board. The connector receptacles on
the back of the cluster electronic circuit board con-
nect the EMIC to the vehicle electrical system
through two take outs with connectors from the vehi-
cle wire harness. The EMIC rear cover includes a
molded mounting tab and a latch feature that
secures the Remote Keyless Entry (RKE)/immobilizer
module to the back of the cluster. The RKE/immobi-
lizer module is connected to the vehicle electrical sys-
tem through a separate take out and connector of the
vehicle wire harness.
Fig. 1 Instrument Cluster
1 - COVER
2 - BEZEL
3 - INSTRUMENT CLUSTER
4 - STEERING WHEEL
5 - MULTI-FUNCTION SWITCH
6 - SPEED CONTROL SWITCH
Fig. 2 Instrument Cluster Components
1 - LENS
2 - HOOD
3 - CLUSTER HOUSING
4 - REAR COVER
8J - 2 INSTRUMENT CLUSTERVA

GROUNDS
The EMIC receives and supplies a ground path to
several switches and sensors through the following
hard wired circuits:
²Ambient Temperature Sensor Return
(Optional)
²Fuel Level Sensor Return
²Ground
Refer to the appropriate wiring information for
additional details.
COMMUNICATION
The EMIC has provisions for the following commu-
nication circuits:
²CAN Data Bus - High
²CAN Data Bus - Low
²Diagnostic Serial Communication Interface
(SCI) Data Bus Line
Refer to the appropriate wiring information for
additional details.
DIAGNOSIS AND TESTING - INSTRUMENT
CLUSTER
The hard wired inputs to and outputs from the
instrument cluster may be diagnosed and tested
using conventional diagnostic tools and procedures.
Refer to the appropriate wiring information. The wir-
ing information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
If the instrument cluster is completely inoperative,
be certain to check the fused B(+) circuit fuses and
wiring for the instrument cluster. If the cluster gen-
eral illumination is inoperative, be certain to check
the instrument lighting fuse and the input circuit to
the instrument cluster from the exterior lighting cir-
cuitry of the multi-function switch on the steering
column.
Conventional diagnostic methods may not prove
conclusive in the diagnosis of the instrument cluster.
In order to obtain conclusive testing of the instru-
ment cluster, the Controller Area Network (CAN)
data bus network and all of the electronic modules
that provide inputs to or receive outputs from the
instrument cluster must also be checked. The most
reliable, efficient, and accurate means to diagnose
the instrument cluster, the CAN data bus network,
and the electronic modules that provide inputs to or
receive outputs from the instrument cluster requires
the use of a diagnostic scan tool and the appropriate
diagnostic information. The diagnostic scan tool can
provide confirmation that the CAN data bus network
is functional, that all of the modules are sending and
receiving the proper electronic messages over the
CAN data bus, and that the instrument cluster isreceiving the proper hard wired inputs and respond-
ing with the proper hard wired outputs needed to
perform its many functions.
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.
STANDARD PROCEDURE
CLUSTER PROGRAMMING
NOTE: After replacing the Instrument Cluster (IC)
according to the service procedures, determine the
optional equipment on the vehicle by accessing the
sales code information using the Vehicle Identifica-
tion Number (VIN) on DealerCONNECT.
(1) Using the DRBIIIt, selectMISCELLANEOUS
FUNCTIONSin the Instrument Cluster (IC) section.
(2) SelectMODULE SERVICE REPLACE-
MENT.
(3) Following the prompts on the DRBIIIt, enter
the correct parameters that are applicable to the
vehicle. Use the sales code information and visual
inspection to obtain the correct parameters.
CAUTION: Do not lock down the instrument cluster
until the following steps are followed or the instru-
ment cluster may be irreversibly damaged.
(4) After entering the proper parameters into the
IC, turn the ignition switch to the OFF position for
30 seconds, then turn the ignition switch ON.
(5) Test drive the vehicle for at least 10 minutes
before proceeding.
(6) Check ALL modules for any parameterization
DTCs. If any parameterization DTCs are present, one
or more parameters entered into the IC are incorrect.
Verify all parameters entered using the sales code
information and visual inspection of the vehicle.
(7) If the parameters entered are verified as cor-
rect and parameterization DTCs are still present,
refer to the appropriate diagnostic information.
(8) If no parameterization DTCs are present, lock
down the IC.
VAINSTRUMENT CLUSTER 8J - 7

NOTE: Mileage will not be displayed until the IC has
been locked down.
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.
CAUTION: The following procedure is for replace-
ment of an ineffective and unresponsive Instrument
Cluster (IC) with a new unit. If the IC is ineffective
or damaged but still responsive, it may be replaced
using an automatic replacement procedure that will
upload IC parameterization data from the existing IC
to the diagnostic scan tool, then download that data
to the new IC. Refer to the MISCELLANEOUS FUNC-
TIONS menu item under the IC module in the diag-
nostic scan tool, then select MODULE AUTO
REPLACEMENT and follow the scan tool prompts to
replace the IC. Do not lock down the IC until all of
the steps are followed and completed or the new IC
may be irreversibly damaged. This procedure initial-
izes and configures the IC for certain optional
equipment on the vehicle without the need for per-
forming a separate cluster programming procedure.
Failure to correctly parameterize the IC prior to it
being electronically locked down will result in the
IC being incorrectly and irreversibly configured for
improper vehicle equipment options, which will
require the IC be replaced again with another new
and unused unit to resolve.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cluster bezel from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - REMOVAL).
(3) Remove the cluster top cover from the instru-
ment panel. (Refer to 23 - BODY/INSTRUMENT
PANEL/TOP COVER - CLUSTER - REMOVAL).
(4) Remove the two screws that secure the instru-
ment cluster mounting ears to the instrument panel
base structure (Fig. 4).(5) Roll the top of the instrument cluster rearward
far enough to access and release the latch that
secures the Remote Keyless Entry (RKE)/immobilizer
module to the back of the instrument cluster rear
cover and disengage the module from the cluster
(Fig. 5).
Fig. 4 Instrument Cluster Remove/Install
1 - SCREW (2)
2 - COVER
3 - SCREW (2)
4 - INSTRUMENT CLUSTER
5 - LOOP (2)
Fig. 5 RKE/Immobilizer Module
1 - RKE/IMMOBILIZER MODULE
2-LATCH
3 - INSTRUMENT CLUSTER
8J - 8 INSTRUMENT CLUSTERVA

(6) Depress the release (Arrow A) and lift the lever
arm (Arrow B) to disconnect each of the two frame
wire harness connectors for the cluster from the con-
nector receptacles on the back of the cluster housing
(Fig. 6).
(7) Lift the instrument cluster upward far enough
to disengage the two molded plastic pivot loops inte-
gral to the base of the cluster hood from the two
pairs of molded plastic pivot hooks that are integral
to the top of the instrument panel base structure.
(8) Remove the instrument cluster from the instru-
ment panel.
INSTALLATION
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) Position the instrument cluster to the instru-
ment panel.
(2) Align the two molded plastic pivot loops inte-
gral to the base of the cluster hood between the twopairs of molded plastic pivot hooks that are integral
to the top of instrument panel base structure, then
push downward on the top of the cluster until the
loops snap into engagement with the hooks (Fig. 6).
(3) Roll the top of the instrument cluster rearward
to access, reconnect, and latch the two frame wire
harness connectors for the cluster to the connector
receptacles on the back of the cluster housing.
(4) Engage and latch the Remote Keyless Entry
(RKE)/immobilizer module to the back of the instru-
ment cluster rear cover (Fig. 5)
(5) Roll the top of the instrument cluster forward
to position the instrument cluster into the instru-
ment panel.
(6) Install and tighten the two screws that secure
the instrument cluster mounting ears to the instru-
ment panel base structure (Fig. 4). Tighten the
screws to 2 N´m (20 in. lbs.).
(7) Reinstall the cluster top cover onto the instru-
ment panel. (Refer to 23 - BODY/INSTRUMENT
PANEL/TOP COVER - CLUSTER - INSTALLA-
TION).
(8) Reinstall the cluster bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - INSTALLATION).
(9) Reconnect the battery negative cable.
CAUTION: If an ineffective and unresponsive Instru-
ment Cluster (IC) has been replaced with a new
unit, the new IC must be initialized and configured
for certain optional equipment on the vehicle using
a cluster programming procedure. (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER - STANDARD
PROCEDURE - CLUSTER PROGRAMMING). Failure
to correctly perform this programming procedure
(also referred to as parameterization) prior to the IC
being electronically locked down will result in the
IC being incorrectly and irreversibly configured for
improper vehicle equipment options, which will
require the IC be replaced again with another new
and unused unit to resolve.
ABS INDICATOR
DESCRIPTION
An Anti-lock Brake System (ABS) indicator is stan-
dard equipment on all instrument clusters. The ABS
indicator is located near the lower edge of the instru-
ment cluster, to the right of the multi-function indi-
cator display. The ABS indicator consists of the
International Control and Display Symbol icon for
ªFailure of Anti-lock Braking Systemº 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
Fig. 6 Cluster Connectors
1 - STEERING WHEEL
2 - INSTRUMENT CLUSTER
3 - CONNECTOR (2)
VAINSTRUMENT CLUSTER 8J - 9

the left and right turn signal circuits. Each turn sig-
nal indicator Light Emitting Diode (LED) is com-
pletely controlled by the instrument 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, each LED can be illuminated regardless of
the ignition switch position. The LED only illumi-
nates when it is provided a path to ground by the
instrument cluster transistor. The instrument cluster
will turn on the turn signal indicators for the follow-
ing reasons:
²Turn Signal Input- Each time the cluster
detects a turn signal input from the turn signal relay
through the closed turn signal switch circuitry of the
multi-function switch on the hard wired left or right
turn signal circuit, the requested turn signal lamps
and turn signal indicator will be flashed on and off,
and a contactless relay soldered onto the cluster elec-
tronic circuit board will produce a clicking sound to
emulate a conventional turn signal flasher. The turn
signals and the turn signal indicators continue to
flash on and off until the turn signal switch circuitry
of the multi-function switch is opened, or until the
ignition switch is turned to the Off position, which-
ever occurs first.
²Hazard Warning Input- Each time the cluster
detects a hazard warning input from the turn signal
relay through the closed hazard warning switch cir-
cuitry of the multi-function switch on the hard wired
left and right turn signal circuits, all of the turn sig-
nal lamps and both turn signal indicators will be
flashed on and off, and a contactless relay soldered
onto the cluster electronic circuit board will produce
a clicking sound to emulate a conventional hazard
warning flasher. The turn signals and the turn signal
indicators continue to flash on and off until the haz-
ard warning switch circuitry of the multi-function
switch is opened.
An electronic wipers, turn signals and engine start
control module located within the fuse block beneath
the steering column monitors the turn signal circuits
and controls the flash rate of the turn signal relay.
The instrument cluster continually monitors the
right and left turn signal circuits to determine the
proper turn signal and hazard warning indicator
operation, then flashes the proper turn signal indica-
tors and the contactless relay on and off accordingly.
The multi-function switch, the turn signal relay and
the left and right turn signal circuits to the instru-
ment cluster can be diagnosed using conventional
diagnostic tools and methods. For proper diagnosis of
the wipers, turn signals and engine start control
module within the fuse block or the instrument clus-
ter circuitry that controls the turn signal indicators
and the contactless relay, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.WAIT - TO - START INDICATOR
DESCRIPTION
A wait-to-start indicator is standard equipment in
all instrument clusters. The wait-to-start indicator is
located near the lower edge of the instrument cluster,
to the right of the multi-function indicator display.
The wait-to-start indicator consists of the Interna-
tional Control and Display Symbol icon for ªDiesel
Preheatº 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. 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 wait-to-start indicator is
serviced as a unit with the instrument cluster.
OPERATION
The wait-to-start indicator gives an indication to
the vehicle operator when the diesel engine glow
plugs are energized in their pre-heat operating mode.
This indicator is controlled by a transistor on the
instrument cluster circuit board based upon cluster
programming and electronic messages received by
the cluster from the Engine Control Module (ECM)
over the Controller Area Network (CAN) data bus.
The wait-to-start 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
detects that the ignition switch is in the On position.
Therefore, the LED will always be off when the igni-
tion 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 wait-to-start indicator for the
following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the wait-to-start indicator
is illuminated for about two seconds as a bulb test.
²Wait-To-Start Lamp-On Message- Each time
the cluster receives a wait-to-start lamp-on message
from the ECM indicating that the diesel engine glow
plugs are energized in their pre-heat operating mode,
the wait-to-start indicator will be illuminated. The
indicator remains illuminated until the cluster
receives a wait-to-start lamp-off message indicating
that the pre-heat mode of the glow plugs has been
completed, until the ECM detects that the engine is
running, or until the ignition switch is turned to the
Off position, whichever occurs first.
8J - 28 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