fuse MERCEDES-BENZ SPRINTER 2005 Service User Guide

The EMIC modules for this model are serviced only
as complete units. The EMIC module cannot be
adjusted or repaired. If a gauge, an LED indicator,
the multi-fuction indicator LCD unit, an electronic
tone generator, the electronic circuit board, the cir-
cuit board hardware, the cluster overlay, the cluster
housing, the cluster hood, the cluster lens, or the
cluster rear cover are damaged or faulty, the entire
EMIC module must be replaced.
OPERATION
The ElectroMechanical Instrument Cluster (EMIC)
is designed to allow the vehicle operator to monitor
the conditions of many of the vehicle components and
operating systems. The gauges, meters and indicators
in the EMIC provide valuable information about the
powertrain, fuel and emissions systems, cooling sys-
tem, lighting systems, safety systems and many
other convenience items. The EMIC is installed in
the instrument panel so that all of these monitors
can be easily viewed by the vehicle operator when
driving, while still allowing relative ease of access for
service. The microprocessor-based EMIC hardware
and software uses various inputs to control the
gauges and indicators visible on the face of the clus-
ter. Some of these inputs are hard wired, but many
are in the form of electronic messages that are trans-
mitted by other electronic modules over the Control-
ler Area Network (CAN) data bus network. (Refer to
8 - ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/COMMUNICATION - OPERATION).
The EMIC microprocessor smooths the input data
using algorithms to provide gauge readings that are
accurate, stable and responsive to operating condi-
tions. These algorithms are designed to provide
gauge readings during normal operation that are con-
sistent with customer expectations. However, when
abnormal conditions exist such as high coolant tem-
perature, the algorithm can drive the gauge pointer
to an extreme position and the microprocessor can
sound a chime through the on-board audible tone
generator to provide distinct visual and audible indi-
cations of a problem to the vehicle operator. The
instrument cluster circuitry also provides audible
turn signal and hazard warning support by emulat-
ing the ªtickingº sound associated with a conven-
tional electro-mechanical flasher using a contactless
relay. The relay will also provide an indication of a
turn signal failure by sounding at double the usual
frequency. Each audible warning is provided to the
vehicle operator to supplement a visual indication.
The EMIC circuitry operates on battery current
received through a non-switched fused B(+) circuit,
and on a fused ignition switch output circuit. The
EMIC circuitry is grounded through a ground circuit
and take out of the frame wire harness with an eye-let terminal connector that is secured to a stud by a
nut at a ground location on the dash panel just for-
ward of the instrument cluster. Separate switched
ground inputs from the key-in ignition switch and
the front door jamb switches provide wake-up signals
to the EMIC circuitry. This arrangement allows the
EMIC to provide some features regardless of the igni-
tion switch position, while other features will operate
only with the ignition switch in the On position.
Proper diagnosis and testing of the EMIC, the
CAN data bus, the data bus electronic message
inputs to and outputs from the EMIC, as well as the
retrieval or erasure of a Diagnostic Trouble Code
(DTC) requires the use of a DRBIIItscan tool. Refer
to the appropriate diagnostic information. See the
owner's manual in the vehicle glove box for more
information on the features, use and operation of the
EMIC.
GAUGES
All gauges receive battery current through the
EMIC circuitry only when the instrument cluster
detects the ignition switch is in the On position. With
the ignition switch in the Off position, battery cur-
rent is not supplied to any gauges and the EMIC cir-
cuitry is programmed to move all of the gauge
needles back to the low end of their respective scales.
Therefore, the gauges do not accurately indicate any
vehicle condition unless the ignition switch is in the
On position.
All of the EMIC gauges are air core magnetic
units. Two fixed electromagnetic coils are located
within each gauge. These coils are wrapped at right
angles to each other around a movable permanent
magnet. The movable magnet is suspended within
the coils on one end of a pivot shaft, while the gauge
needle is attached to the other end of the shaft. One
of the coils has a fixed current flowing through it to
maintain a constant magnetic field strength. Current
flow through the second coil changes, which causes
changes in its magnetic field strength. The current
flowing through the second coil is changed by the
EMIC circuitry in response to messages received over
the CAN data bus. The gauge needle moves as the
movable permanent magnet aligns itself to the
changing magnetic fields created around it by the
electromagnets.
Proper diagnosis and testing of the gauges, the
CAN data bus and the electronic data bus message
inputs to the EMIC that control each gauge require
the use of a DRBIIItscan tool. Refer to the appro-
priate diagnostic information. Specific operation
details for each gauge may be found elsewhere in
this service information.
VAINSTRUMENT CLUSTER 8J - 5
INSTRUMENT CLUSTER (Continued)

INDICATORS
Indicators are located in various positions within
the EMIC and are all connected to the EMIC elec-
tronic circuit board. The ambient temperature indica-
tor (optional), brake indicator, brake wear indicator,
charging indicator, coolant low indicator, high beam
indicator, low fuel indicator, seatbelt indicator, turn
signal indicators, and washer fluid indicator operate
based upon hard wired inputs to the EMIC. The air-
bag (SRS) indicator is normally controlled by a hard
wired input from the Airbag Control Module (ACM);
however, if the EMIC sees an abnormal or no input
from the ACM, it will automatically turn the airbag
indicator On until the hard wired input from the
ACM has been restored. The Malfunction Indicator
Lamp (MIL) is normally controlled by CAN data bus
messages from the Engine Control Module (ECM);
however, if the EMIC loses CAN data bus communi-
cation, the EMIC circuitry will automatically turn
the MIL on until CAN data bus communication is
restored. The EMIC uses CAN data bus messages
from the ECM, the ACM, and the Controller Antilock
Brake to control all of the remaining indicators.
The various EMIC indicators are controlled by dif-
ferent strategies; some receive battery feed from the
EMIC circuitry and have a switched ground, while
others are grounded through the EMIC circuitry and
have a switched battery feed. However, all indicators
are completely controlled by the EMIC microproces-
sor based upon various hard wired and electronic
message inputs. Except for the indications provided
by the multi-function indicator Liquid Crystal Dis-
play (LCD) unit, all indicators are illuminated at a
fixed intensity, which is not affected by the selected
illumination intensity of the EMIC general illumina-
tion lamps.
The hard wired indicator inputs may be diagnosed
using conventional diagnostic methods. However,
proper testing of the EMIC circuitry and the CAN
bus message controlled indicators requires the use of
a DRBIIItscan tool. Refer to the appropriate diag-
nostic information. Specific details of the operation
for each indicator may be found elsewhere in this
service information.
CLUSTER ILLUMINATION
The EMIC has several general illumination lamps
that are illuminated when the exterior lighting is
turned on with the multi-function switch. The illumi-
nation intensity of these lamps is adjusted by a dim-
ming level input received from the multi-function
indicator ª+º (plus) and ª±º (minus) switch push but-
tons that extend through the lower edge of the clus-
ter lens below the right end of the multi-function
indicator. When the exterior lighting is turned Off,
the display is illuminated at maximum brightness.When the exterior lighting is turned On and the
transmission gear selector is in the Park position,
depressing the plus switch push button brightens the
display lighting, and depressing the minus switch
push button dims the display lighting. The EMIC
also provides a Pulse-Width Modulated (PWM) panel
lamps dimmer output that can be used to synchro-
nize the illumination lighting levels of external illu-
mination lamps (up to about 23 to 30 watts) with
that of the EMIC.
The hard wired multi-function switch input and
the EMIC panel lamps dimmer output may be diag-
nosed using conventional diagnostic methods. How-
ever, proper testing of the PWM control of the EMIC
and the electronic dimming level inputs from the
multi-function indicator push buttons requires the
use of a DRBIIItscan tool. Refer to the appropriate
diagnostic information.
INPUT AND OUTPUT CIRCUITS
HARD WIRED INPUTS
The hard wired inputs to the EMIC include the fol-
lowing:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
²Airbag Indicator Driver
²Ambient Temperature Sensor Signal
(Optional)
²Brake Wear Indicator Sense
²Charging Indicator Driver
²Coolant Level Switch Sense
²Front Door Jamb Switch Sense
²Fuel Level Sensor Signal
²Fused B(+)
²Fused Ignition Switch Output
²High Beam Indicator Driver
²Key-In Ignition Switch Sense
²Left Turn Signal
²Park Brake Switch Sense
²Right Turn Signal
²Seat Belt Switch Sense
²Washer Fluid Switch Sense (Optional)
Refer to the appropriate wiring information for
additional details.
HARD WIRED OUTPUTS
The hard wired outputs of the EMIC include the
following:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
²Engine Running Relay Control
²Panel Lamps Driver
8J - 6 INSTRUMENT CLUSTERVA
INSTRUMENT CLUSTER (Continued)

Refer to the appropriate wiring information for
additional details.
GROUNDS
The EMIC receives and supplies a ground path to
several switches and sensors through the following
hard wired circuits:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
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:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
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 theinstrument 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 DRBIIItscan tool and the appropriate
diagnostic information. The DRBIIItscan 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 is
receiving the proper hard wired inputs and respond-
ing with the proper hard wired outputs needed to
perform its many functions.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BAT-
TERY NEGATIVE (GROUND) CABLE, THEN WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR TO
DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL SUPPLEMENTAL RESTRAINT DEPLOY-
MENT AND POSSIBLE PERSONAL INJURY.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BAT-
TERY NEGATIVE (GROUND) CABLE, THEN WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR TO
DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL SUPPLEMENTAL RESTRAINT DEPLOY-
MENT AND POSSIBLE PERSONAL INJURY.
(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).
VAINSTRUMENT CLUSTER 8J - 7
INSTRUMENT CLUSTER (Continued)

nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the instrument cluster
circuitry that controls the fuel gauge, a DRBIIItscan
tool is required. Refer to the appropriate diagnostic
information.
GEAR SELECTOR INDICATOR
DESCRIPTION
An electronic automatic transmission gear selector
indicator is standard equipment on all instrument
clusters. The gear selector indicator information is
displayed in the center of the multi-function indicator
Liquid Crystal Display (LCD) located near the lower
edge of the instrument cluster, directly below the
speedometer. The gear selector indicator displays the
following characters as they are selected: ªP,º ªR,º
ªN,º ªD,º ª4,º ª3,º ª2,º and ª1.º Respectively, these
characters represent the currently selected park,
reverse, neutral, drive, fourth gear, third gear, second
gear, and first gear positions of the transmission gear
selector lever on the instrument panel.
The indications of the gear selector indicator are
not visible unless the multi-function indicator LCD is
illuminated and the engine is running. When illumi-
nated, each indication appears as a dark character
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 concert with the cluster general illumina-
tion lighting using the ª+º (plus) and ª2º (minus)
multi-function indicator push buttons. The gear
selector indicator is serviced as a unit with the
instrument cluster.
OPERATION
The electronic gear selector indicator gives an indi-
cation to the vehicle operator of the transmission
gear that is currently selected with the automatic
transmission gear selector lever. This indicator is
controlled by the instrument cluster circuit board
based upon cluster programming and electronic mes-
sages received from the Transmission Control Module
(TCM) over the Controller Area Network (CAN) data
bus. The gear selector indicator information is dis-
played by the multi-function indicator Liquid Crystal
Display (LCD) unit on the instrument cluster elec-
tronic circuit board. The multi-function indicator
LCD is completely controlled by the instrument clus-
ter logic circuit, and that logic will only allow the
gear selector indicator information to be displayed
when the instrument cluster detects that the ignition
switch is in the On position. Therefore, the gearselector indicator will always be off when the ignition
switch is in any position except On.
The TCM continually monitors the transmission
range sensor, then sends the proper gear selector
indicator position messages to the instrument cluster.
For proper diagnosis of the transmission range sen-
sor, the TCM, the CAN data bus, or the electronic
message inputs to the instrument cluster that control
the gear selector indicator, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
HIGH BEAM INDICATOR
DESCRIPTION
A high beam indicator is standard equipment on
all instrument clusters. The high beam indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
high beam indicator consists of the International
Control and Display Symbol icon for ªHigh Beamº
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. A
blue Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the icon to
appear silhouetted against a blue field through the
translucent outer layer of the overlay when the indi-
cator is illuminated from behind by the LED, which
is soldered onto the instrument cluster electronic cir-
cuit board. The high beam indicator is serviced as a
unit with the instrument cluster.
OPERATION
The high beam indicator gives an indication to the
vehicle operator whenever the headlamp high beams
are illuminated. This indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and a hard wired
input from the multi-function switch. The high beam
indicator Light Emitting Diode (LED) is completely
controlled by the instrument cluster logic circuit, and
that logic will allow this indicator to operate when-
ever the instrument cluster receives battery current
on the fused B(+) circuit. Therefore, the LED can be
illuminated regardless of the ignition switch position.
The LED only illuminates when it is provided a path
to ground by the instrument cluster transistor. The
instrument cluster will turn on the high beam indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the high beam indicator is
illuminated by the cluster for about two seconds as a
bulb test.
VAINSTRUMENT CLUSTER 8J - 17
FUEL GAUGE (Continued)

wired input received by the cluster from the turn sig-
nal relay through the turn signal and hazard warn-
ing switch circuitry of the multi-function switch on
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 controlmodule within the fuse block or the instrument clus-
ter circuitry that controls the turn signal indicators
and the contactless relay, a DRBIIItscan 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,
8J - 26 INSTRUMENT CLUSTERVA
TURN SIGNAL INDICATOR (Continued)

REAR SIDE MARKER LAMP BULB
REMOVAL.............................21
INSTALLATION.........................21
REAR TURN LAMP BULB
REMOVAL.............................21
INSTALLATION.........................22
REPEATER LAMP BULB
REMOVAL.............................22
INSTALLATION.........................22REPEATER LAMP UNIT
REMOVAL.............................22
INSTALLATION.........................23
TAIL LAMP UNIT
REMOVAL.............................23
INSTALLATION.........................23
TURN SIGNAL RELAY
REMOVAL.............................24
INSTALLATION.........................24
LAMPS/LIGHTING - EXTERIOR
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.
8L - 2 LAMPS/LIGHTING - EXTERIORVA

²Trailer Tow Connector- Vehicles equipped
with a factory-approved, field-installed trailer towing
electrical package have a heavy duty 7-way trailer
tow connector installed in a bracket on the trailer
hitch receiver. This package includes a 7-way to
4-way connector adapter unit.
²Trailer Tow Control Module- Vehicles
equipped with a factory-approved, field-installed
trailer towing electrical package have a trailer tow
brake/turn control module located within the driver
side front seat riser that controls the brake lamp and
turn signal lamp outputs to the trailer lighting cir-
cuits.
²Turn Signal Relay- A turn signal relay is
installed in the fuse block located on the underside of
the steering column behind a fuse access panel in the
steering column opening cover on the instrument
panel. The electronic circuitry of the wipers, turn sig-
nals and engine start control module within the fuse
block controls the turn signal relay.
²Wipers, Turn Signals, Engine Start Control
Module- The wipers, turn signals and engine start
control module is integral to the fuse block located on
the underside of the steering column behind a fuse
access panel in the steering column opening cover on
the instrument panel. This module includes active
electronic elements that control the operation of the
turn signal relay based upon inputs from the multi-
function switch and feedback from the turn signal
circuits. (Refer to 8 - ELECTRICAL/POWER DISTRI-
BUTION/FUSE BLOCK - DESCRIPTION).
Hard wired circuitry connects the exterior lighting
system components to the electrical system of the
vehicle. These hard wired circuits are integral to sev-
eral wire harnesses, which are routed throughout the
vehicle and retained by many different methods.
These circuits may be connected to each other, to the
vehicle electrical system and to the exterior lighting
system components through the use of a combination
of soldered splices, splice block connectors, and many
different types of wire harness terminal connectors
and insulators. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
OPERATION
Following are paragraphs that briefly describe the
operation of each of the major exterior lighting sys-
tems. The hard wired circuits and components of the
exterior lighting systems may be diagnosed and
tested using conventional diagnostic tools and proce-
dures. However, conventional diagnostic methods
may not prove conclusive in the diagnosis of the wip-ers, turn signals and engine start control module
located within the fuse block underneath the steering
column, the ElectroMechanical Instrument Cluster
(EMIC), the Engine Control Module (ECM), or the
Controller Area Network (CAN) data bus network.
The most reliable, efficient, and accurate means to
diagnose the electronic module within the fuse block,
the EMIC, the ECM, and the CAN data bus network
inputs and outputs related to the various exterior
lighting systems requires the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
BACKUP LAMPS
The backup (or reverse) lamps have a path to
ground received at all times through the vehicle wire
harness from a ground point located on the frame
near the left end of the tailgate sill. The backup
lamps receive battery current on the backup lamp
supply circuit only when the backup lamp switch cir-
cuit of the Transmission Range Sensor (TRS) integral
to the gear shifter assembly is closed by the gear
shifter mechanism.
BRAKE LAMPS
The brake (or stop) lamps have a path to ground at
all times through the vehicle wire harness from a
ground point located on the frame near the left end
of the tailgate sill. The Center High Mounted Stop
Lamp (CHMSL) has a path to ground at all times
through the vehicle wire harness from a ground point
on the left side of the dash panel. The brake lamps
and CHMSL receive battery current on the brake
lamp switch output circuit when the brake lamp
switch is closed by the brake pedal arm.
DAYTIME RUNNING LAMPS
Vehicles manufactured for sale in Canada illumi-
nate the low beam headlamp bulb when the engine is
running and the exterior lamps are turned off. This
feature is enabled by the right and left Daytime Run-
ning Lamps (DRL) relays. When the DRL relays are
de-energized, they provide fused battery current from
the circuit K26 relay to the headlamp low beams.
When the headlamps are turned On using the left
(lighting) control stalk of the multi-function switch
the DRL relays are energized, which returns control
of the headlamps to the headlamp switch circuitry of
the multi-function switch. The circuit K26 relay is
energized by the Electro-Mechanical Instrument
Cluster (EMIC) whenever it receives an electronic
message from the Engine Control Module (ECM) over
the Controller Area Network (CAN) data bus indicat-
ing that the engine is running. The DRL and circuit
K26 relays are installed in a relay bracket located
below the forward edge of the driver side front seat
cushion within the driver side front seat riser.
VALAMPS/LIGHTING - EXTERIOR 8L - 3
LAMPS/LIGHTING - EXTERIOR (Continued)

FRONT FOG LAMPS
Vehicles equipped with optional front fog lamps
have a front fog lamp relay installed in a relay
bracket located below the forward edge of the driver
side front seat cushion within the driver side front
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.
TURN SIGNAL LAMPS
When the left (lighting) control stalk of the multi-
function switch is activated (Fig. 1), the turn signal
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
LAMPS/LIGHTING - EXTERIOR (Continued)

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 -
EXTERIOR
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).
(5) Remove the backup lamp bulb from the tail
lamp socket plate.
Fig. 2 Tail Lamp Socket Plate Remove/Install
1 - SOCKET PLATE
2 - INNER REAR PILLAR
3 - LATCH TAB (2)
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
VALAMPS/LIGHTING - EXTERIOR 8L - 5
LAMPS/LIGHTING - EXTERIOR (Continued)

(3) Disconnect the front lamp unit wire harness
connector from the low beam headlamp bulb base
(Fig. 36).
(4) Disengage the low beam headlamp bulb
retainer by pushing it slightly toward the front lamp
unit housing and downward from the bulb base, then
pivot the retainer off of the bulb base.
(5) Remove the low beam headlamp bulb from the
integral bulb holder on the front lamp unit reflector.
INSTALLATION
(1) Position the low beam headlamp bulb into the
integral bulb holder on the front lamp unit reflector.
Be certain that the lugs on the bulb base are
engaged in the recesses of the bulb holder (Fig. 36).
(2) Engage the low beam headlamp bulb retainer
by pivoting it over the bulb base, pressing it slightly
toward the front lamp unit housing and upward
toward the side of the bulb base.
(3) Reconnect the front lamp unit wire harness
connector to the low beam headlamp bulb base.
(4) Position the front lamp unit rear cover onto the
lamp housing and engage the retainers over each
side of the cover to secure it (Fig. 35).
(5) Reconnect the battery negative cable.
MULTI-FUNCTION SWITCH
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,PASSENGER AIRBAG, SEAT BELT TENSIONER, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BAT-
TERY NEGATIVE (GROUND) CABLE, THEN WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR TO
DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the fuse block from the underside of
the steering column. (Refer to 8 - ELECTRICAL/
POWER DISTRIBUTION/FUSE BLOCK - REMOV-
AL).
(3) Remove the clockspring from the steering col-
umn. (Refer to 8 - ELECTRICAL/RESTRAINTS/
CLOCKSPRING - REMOVAL).
(4) Remove the two screws that secure the upper
shroud to the top of the multi-function switch (Fig.
37).
(5) Remove the upper shroud from the top of the
multi-function switch.
(6) Remove the two screws that secure the multi-
function switch to the steering column.
(7) Remove the multi-function switch from the
steering column.
(8) Remove the speed control switch from the back
of the multi-function switch. (Refer to 8 - ELECTRI-
CAL/SPEED CONTROL/SWITCH - REMOVAL).
Fig. 36 Low Beam Headlamp Bulb Remove/Install
1 - LAMP HOUSING
2 - BULB BASE
3 - CONNECTOR
4 - BULB RETAINER
Fig. 37 Multi-Function Switch Remove/Install
1 - SCREW (2)
2 - UPPER SHROUD
3 - SWITCH
4 - SCREW (2)
VALAMPS/LIGHTING - EXTERIOR 8L - 19
LOW BEAM HEADLAMP BULB (Continued)