Instrument cluster DODGE RAM 2003 Service Manual PDF

MULTI-FUNCTION SWITCH
DESCRIPTION - TURN SIGNAL SYSTEM.....17
OPERATION - TURN SIGNAL SYSTEM.......18
DIAGNOSIS AND TESTING - MULTI-
FUNCTION SWITCH...................18
REMOVAL.............................18
INSTALLATION.........................19
PARK LAMP RELAY
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - PARK LAMP
RELAY..............................20
REMOVAL.............................20
INSTALLATION.........................21
PARK/TURN SIGNAL LAMP
REMOVAL.............................21
INSTALLATION.........................21TAIL LAMP
REMOVAL.............................21
INSTALLATION.........................21
TAIL LAMP UNIT
REMOVAL.............................21
INSTALLATION.........................21
TRAILER TOW WIRING
DESCRIPTION.........................22
TURN LAMP
REMOVAL.............................22
INSTALLATION.........................22
UNDERHOOD LAMP
REMOVAL.............................22
INSTALLATION.........................22
UNDERHOOD LAMP UNIT
REMOVAL.............................22
INSTALLATION.........................23
LAMPS/LIGHTING - EXTERIOR
DESCRIPTION
The exterior lighting system for this model include
the following components:
²Backup Lamps
²Brake Lamps
²Daytime Running Lamps
²Front Fog Lamps
²Hazard Warning Lamps
²Headlamps
²Park Lamps
²Turn Signal Lamps
Other components of the exterior lighting system
for this model include:
²Backup Lamp Switch
²Brake Lamp Switch
²Front Control Module
²Front Fog Lamp Relay
²Hazard Switch
²Multi-Function Switch
²Park Lamp Relay
²Trailer Tow Connectors
Some of the interior and exterior lighting functions
are governed by the front control module. The head-
lamp, dome, and door ajar switchs provide signals to
the instrument cluster. The instrument cluster sends
a J1850 message to the front control module to
enable the necessary components for illumination.
Hard wired circuitry connects the exterior lighting
system components to the electrical system of the
vehicle. Refer to the appropriate wiring information.
OPERATION
DAYTIME RUNNING LAMPS
Power is reduced using pulse-width modulation to
the high beams, where by the power is switched on
and off rapidly instead of remaining on continuously.
The duration and interval of the power pulses is pro-
grammed into the Front Control Module (FCM).
HEADLAMP SYSTEM
The instrument cluster monitors both the multi-
plexed headlamp and multifunction switches. The
instrument cluster transmits a J1850 bus message to
the front control module (FCM) to activate the head-
lamps. The headlamp system will default to head-
lamps ON position when ignition switch is ON and
when an open or short circuit failure occurs on the
headlamp switch input to the instrument cluster. The
system will return to normal operation when the
open or short is repaired. A fault will be reported by
the Instrument Cluster when a failure occurs on the
dimmer or headlamp switch input.
If the exterior lamps are ON, and the headlamp
switch is in any position other than OFF, with the
ignition switch OFF (LOCK) after 5 minutes, the
Instrument Cluster transmits a message via J1850
informing the the FCM. The FCM will then turn off
the headlamps, park lamps and fog lamps. This fea-
ture (load shed) prevents the vehicle battery from
being discharged when the vehicle lights have been
left ON.
HEADLAMP TIME DELAY SYSTEM
The headlamp time delay system is activated by
turning the headlamps ON (high or low beam) while
the engine is running, turning the ignition switch
OFF, and then turning the headlamp switch OFF
8L - 2 LAMPS/LIGHTING - EXTERIORDR

within 45 seconds. The system will not activate if
more than 45 seconds elapse between ignition switch
OFF and headlamp switch OFF. The FCM will allow
the headlamps to remain ON for 60 seconds (config-
urable) before they automatically turn off (If the key
is in the ignition during the headlamp time delay
mode, then the headlamps including panel dimming
will be ON).
LAMP OUTAGE
If one or more of the following lamps (Low and/or
High beams, Brake and/or Turn Signal) are out, then
a ªlamps outº indicator located in the cluster will
illuminate.
OPTICAL HORN/HIGH BEAMS
When the multiplexed multifunction switch is
pulled to the first detent (optical horn) signal, the
headlamps are ON, the Instrument Cluster shall
send a message via J1850 to the FCM to turn on the
headlamps drivers to illuminate all four filaments
(Low and High beams). When the multifunction
switch is pulled to the second detent (high beam) sig-
nal and the headlamps are ON, the Instrument Clus-
ter shall send a message via J1850 to the FCM to
turn on the headlamps drivers. The High Beams are
illuminated and the Low Beams and Fog Lamps (if
ON) are extinguished. If the headlamps were in the
high beam configuration when power was removed
from the headlamps, the headlamps will return to
their last state prior to being shut off.
DIAGNOSIS AND TESTING - LAMPS/LIGHTING
- EXTERIOR
WARNING: EYE PROTECTION SHOULD BE USED
WHEN SERVICING GLASS COMPONENTS. PER-
SONAL INJURY CAN RESULT.
CAUTION: Do not touch the glass of halogen bulbs
with fingers or other possibly oily surface, reduced
bulb life will result. Do not use bulbs other than
those indicated in the Bulb Application table. Dam-
age to lamp and/or Daytime Running Lamp Module
can result. Do not use fuses, circuit breakers or
relays having greater amperage value than indi-
cated on the fuse panel or in the Owners Manual.
When a vehicle experiences problems with the
headlamp system, verify the condition of the battery
connections, fuses, charging system, headlamp bulbs,
wire connectors, relay, multifunction switch, and
headlamp switch. Refer to the appropriate wiring
information.
Each vehicle is equipped with various lamp assem-
blies. A good ground is necessary for proper lighting
operation. Grounding is provided by the lamp socket
when it comes in contact with the metal body, or
through a separate ground wire.
When changing lamp bulbs check the socket for
loose pin connections and corrosion. Repair as neces-
sary.
When it is necessary to remove components to ser-
vice another, it should not be necessary to apply
excessive force or bend a component to remove it.
Before damaging a trim component, verify hidden
fasteners or captured edges are not holding the com-
ponent in place.
DRLAMPS/LIGHTING - EXTERIOR 8L - 3
LAMPS/LIGHTING - EXTERIOR (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
HEADLAMPS DO NOT
ILLUMINATE1. No voltage to headlamps. 1. Repair open headlamp circuit, refer to
Electrical, Wiring Information.
2. No ground at headlamps. 2. Repair circuit ground, refer to Electrical,
Wiring Information.
3. Broken connector terminal or
wire splice in headlamp circuit.3. Repair connector terminal or wire splice.
4. Faulty or burned out bulb. 4. Replace headlamp bulb(s).
5. Integrated Control Module
malfunction.5. Refer to appropriate Body Control Module
diagnostics.
6. J1850 Bus Communication 6. Verify messages being transmitted by
Instrument Cluster and received by FCM.
7. Front Control Module
Malfunction.7. Refer to appropriate ICM/FCM diagnostics.
HEADLAMPS ON WITH
IGNITION IN RUN, WITH
HEADLAMP SWITCH
OFF1. Faulty headlamp switch. 1. Replace headlamp switch (review Instrument
Cluster logged faults).
2. Diagnostic tool indicates (4.7 -
5.0V) on headlamp switch input to
Instrument Cluster.2. Inspect and repair terminals, connectors and
open circuits.
3. J1850 Bus Communication. 3. Verify messages being transmitted by
Instrument Cluster and received by FCM.
4. Front Control Module
Malfunction.4. Refer to appropriate ICM/FCM diagnostics.
FOG LAMP DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM
WITH ENGINE IDLING
OR IGNITION TURNED
OFF.1. Loose or corroded battery
cables.1. Clean and secure battery cable clamps and
posts.
2. Loose or worn generator drive
belt.2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system. Refer to
Electrical, Charging,
4. Battery has insufficient charge. 4. Test battery state-of-charge. Refer to
Electrical, Battery System.
5. Battery is sulfated or shorted. 5. Load test battery. Refer to Electrical, Battery
System.
6. Poor lighting circuit ground. 6. Test for voltage drop across ground
locations. Refer to Electrical, Wiring
Information.
FOG LAMP BULBS
BURN OUT
FREQUENTLY1. Charging system output too
high.1. Test and repair charging system. Refer to
Electrical, Charging.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and splices.
Refer to Electrical, Wiring Information.
DRLAMPS/LIGHTING - EXTERIOR 8L - 5
LAMPS/LIGHTING - EXTERIOR (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM
WITH ENGINE
RUNNING ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system. Refer to
Electrical, Charging.
2. Poor lighting circuit ground. 2. Test for voltage drop across ground
locations. Refer to Electrical, Wiring
Information.
3. High resistance in fog lamp
circuit.3. Test amperage draw of fog lamp circuit.
FOG LAMPS FLASH
RANDOMLY1. Poor lighting circuit ground. 1. Test for voltage drop across ground
locations. Refer to Electrical, Wiring
Information.
2. Variable resistance in fog lamp
circuit.2. Test amperage draw of fog lamp circuit.
3. Faulty fog lamp switch (part of
headlamp switch).3. Replace headlamp switch.
4. Loose or corroded terminals or
splices in circuit.4. Inspect and repair all connectors and splices.
Refer to Electrical, Wiring Information.
5. Is relay engaging properly? 5. Verify function of fog lamp relay in IPM.
6. J1850 Bus Communication. 6. Verify J1850 message (fog lamp info)
transmitted from Instrument Cluster and
received by FCM.
FOG LAMPS DO NOT
ILLUMINATE1. Blown fuse for fog lamp. 1. Replace fuse. Refer to Electrical, Wiring
Information.
2. No ground at fog lamps. 2. Repair circuit ground. Refer to Electrical,
Wiring Information.
3. Faulty fog lamp switch (part of
headlamp switch).3. Replace headlamp switch.
4. Broken connector terminal or
wire splice in fog lamp circuit.4. Repair connector terminal or wire splice.
5. Faulty or burned out bulb. 5. Replace bulb.
6. Is relay engaging? 6. Verify function of fog lamp relay in IPM.
7. J1850 Bus Communication. 7. Verify J1850 message (fog lamp info)
transmitted from Instrument Cluster and
received by FCM.
DAYTIME RUNNING LAMP (CANADA ONLY) DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
DAYTIME RUNNING
LAMPS DO NOT
OPERATE1. Parking brake engaged. 1. Disengage parking brake.
2. Parking brake circuit shorted
to ground.2. Check cluster telltale, refer to the appropriate
wiring information.
3. Headlamp circuit shorted to
ground.3. Refer to the appropriate wiring information.
4. FCM, Instrument Cluster not
programed with Canadian
country code.4. Check country code.
8L - 6 LAMPS/LIGHTING - EXTERIORDR
LAMPS/LIGHTING - EXTERIOR (Continued)

OPERATION
The backup lamp switch controls the flow of bat-
tery voltage to the backup lamp bulbs through an
output on the back-up lamp feed circuit. The switch
plunger is mechanically actuated by the gearshift
mechanism within the transmission, which will
depress the switch plunger and close the switch con-
tacts whenever the reverse gear has been selected.
The switch receives battery voltage through a fuse in
the Integrated Power Module (IPM) on a fused igni-
tion switch output (run) circuit whenever the ignition
switch is in the On position. A take out of the engine
wire harness connects the backup lamp switch to the
vehicle electrical system. The backup lamp switch
and circuits can be tested using conventional diag-
nostic tools and methods.
DIAGNOSIS AND TESTING - BACKUP LAMP
SWITCH
(1) Disconnect and isolate the battery negative
cable.
(2) Raise and support the vehicle.
(3) Locate and disconnect the engine wire harness
connector for the backup lamp switch.
(4) Check for continuity between the two terminal
pins in the backup lamp switch connector.
(a) With the gear selector lever in the Reverse
position, there should be continuity.
(b) With the gear selector lever in any position
other than Reverse, there should be no continuity.
BRAKE LAMP
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the tail lamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/TAIL
LAMP UNIT - REMOVAL).
(3) Remove the bulb back plate from the tail lamp
unit.
(4) Remove the bulb from the back plate.
INSTALLATION
(1) Install the bulb into the back plate.
(2) Install the bulb back plate to the tail lamp
unit.
(3) Install the tail lamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/TAIL
LAMP UNIT - INSTALLATION).
(4) Connect the negative battery cable.
BRAKE LAMP SWITCH
DESCRIPTION
The plunger type brake lamp switch is mounted on
a bracket attached to the base of the steering col-
umn, under the instrument panel.
CAUTION: The switch can only be adjusted during
initial installation. If the switch is not adjusted prop-
erly a new switch must be installed.
OPERATION
The brake lamp switch is hard wired to the Center
High Mount Stop Lamp (CHMSL) and also moni-
tored by the Instrument Cluster for use by the brake
lamp, speed control brake sensor circuits and elec-
tronic brake distribution (EBD). The brake lamp cir-
cuit is open until the plunger is depressed. The speed
control and brake sensor circuits are closed until the
plunger is depressed. When the brake lamp switch
transitions, the CHMSL transitions and instrument
cluster transmits a brake applied/released message
on the bus. The Integrated Power Module (IPM) will
then transition the brake lamps.
When the brake light switch is activated, the Pow-
ertrain Control Module (PCM) receives an input indi-
cating that the brakes are being applied. After
receiving this input, the PCM maintains idle speed to
a scheduled rpm through control of the Idle Air Con-
trol (IAC) motor. The brake switch input is also used
to disable vent and vacuum solenoid output signals
to the speed control servo.
Fig. 1 Backup Lamp Switch - Typical
1 - MANUAL TRANSMISSION
2 - BACKUP LAMP SWITCH
3 - ENGINE WIRE HARNESS
8L - 8 LAMPS/LIGHTING - EXTERIORDR
BACKUP LAMP SWITCH (Continued)

(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
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,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER 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 cover for the Power Distribution
Center (PDC).
(3) Remove the front fog lamp relay by grasping it
firmly and pulling it straight out from the receptacle
in the PDC.
INSTALLATION
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,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER 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) Position the front fog lamp relay to the proper
receptacle in the Power Distribution Center (PDC).
(2) Align the front fog lamp relay terminals with
the terminal cavities in the PDC.
(3) Press firmly and evenly on the top of the front
fog lamp relay until the terminals are fully seated in
the PDC.
(4) Reconnect the battery negative cable.
HAZARD SWITCH
DESCRIPTION
The hazard switch is activated by a push button
located in the multifunction switch on the top of the
steering column between the steering wheel and
instrument cluster.
The hazard warning system allows the vehicle
operator to provide other vehicle operators in the
near proximity an optical indication that the vehicle
is disabled or an obstacle to traffic flow. The hazard
warning system has battery voltage at all times,
regardless of ignition position.
OPERATION
The instrument cluster monitors the multiplexed
multifunction switch operation. When the hazard
warning switch is activated, the instrument cluster
will send a J1850 bus message to the Front Control
Module (FCM), then activate the two turn signal indi-
cators and audible click in the instrument cluster.
The FCM will then activate the necessary relays in
the Power Distribution Center (PDC) to begin flash-
ing both the front and rear turn signal indicator
lamps.
HEADLAMP
REMOVAL
(1) Disconnect and isolate the negitive battery
cable.
(2) Remove the headlamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - REMOVAL).
(3) Seperate the socket from the headlamp unit.
INSTALLATION
CAUTION: Do Not Touch the bulb glass with fingers
or other oily surfaces. Reduced bulb life will result.
(1) Install the socket into the headlamp unit.
(2) Install the headlamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - INSTALLATION).
(3) Connect the negitive battery cable.
DRLAMPS/LIGHTING - EXTERIOR 8L - 13
FOG LAMP RELAY (Continued)

HEADLAMP SWITCH
DESCRIPTION
The multiplexed headlamp switch is located on the
instrument panel. The headlamp switch controls the
parking lamps, fog lamps and the headlamps. A sep-
arate switch in the module controls the interior
lamps and instrument cluster illumination. This
switch also contains a rheostat for controlling the
illumination level of the cluster lamps.
OPERATION
The multiplexed headlamp switch has an off, park-
ing lamp, fog lamp and a headlamp on position. High
beams are controlled by the multiplexed multifunc-
tion switch on the steering column. The fog lamps
are illuminated by pulling back on the headlamp
switch knob when in the parking lamp or headlamp
ON position.The headlamp switch cannot be
repaired. It must be replaced.
The Instrument Cluster monitors the headlamp
and multifunction switch operation. When the head-
lamp switch is rotated to the parking lamp or On
position the Instrument Cluster sends a J1850 mes-
sage to the Front Control Module, which is mated to
the power distribution center to become the Inte-
grated Control Module, to illuminate the appropriate
bulbs. When the multifunction switch is activated to
the optical horn or high beam position the Instru-
ment Cluster illuminates the high beam indicator
and sends a J1850 message to the Front Control
Module to illuminate the appropriate bulbs.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the left instrument panel bezel. (Refer
to 23 - BODY/INSTRUMENT PANEL/CLUSTER
BEZEL - REMOVAL).
(3) Disconnect the harness connector.(4) Remove the screws that secure the headlamp
switch to the instrument panel bezel (Fig. 9).
(5) Remove the headlamp switch from the instru-
ment panel bezel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Position the headlamp switch to the left instru-
ment panel bezal and secure with screws.Tighten the
screws to 2.2 N´m (20 in. lbs.).
(2) Reconnect the instrument panel wire harness
connector for the headlamp switch.
(3) Position the left instrument panel bezal on to
the instrument panel.
Fig. 9 Headlamp Switch Removal
1 - DASH BOARD
2 - HEADLAMP SWITCH
3 - INSTRUMENT PANEL BEZAL
8L - 14 LAMPS/LIGHTING - EXTERIORDR

(4) Install the cluster bezel onto the instrument
panel (Fig. 9).
(5) Connect the battery negative cable.
HEADLAMP UNIT
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the push pins attaching the seal to the
fender.
(3) Remove the bolts attaching the headlamp unit
to the fender (Fig. 10).
(4) Remove the bulb sockets from the headlamp
unit
(5) Separate headlamp unit from vehicle.
INSTALLATION
CAUTION: Do not touch the bulb glass with fingers
or other oily surfaces. Reduced bulb life will result.
(1) Install the bulb sockets for the front park/turn
signal and headlamp.
(2) Position headlamp unit in inner fender panel.
(3) Install the bolts attaching headlamp unit to the
fender (Fig. 10).
(4) Align the seal and install the push pins.
(5) Connect the battery negative cable.
ADJUSTMENTS
Headlamps can be aligned using the screen method
provided in this section. Alignment Tool C-4466-A or
equivalent can also be used. Refer to instructions
provided with the tool for proper procedures.
LAMP ALIGNMENT SCREEN PREPARATION
(1) Position vehicle on a level surface perpendicu-
lar to a flat wall 7.62 meters (25 ft) away from front
of headlamp lens (Fig. 11).
(2) If necessary, tape a line on the floor 7.62
meters (25 ft) away from and parallel to the wall.
(3) Up 1.27 meters (5 feet) from the floor, tape a
line on the wall at the centerline of the vehicle. Sight
along the centerline of the vehicle (from rear of vehi-
cle forward) to verify accuracy of the line placement.
(4) Rock vehicle side-to-side three times to allow
suspension to stabilize.
(5) Jounce front suspension three times by pushing
downward on front bumper and releasing.
(6) Measure the distance from the center of head-
lamp lens to the floor. Transfer measurement to the
alignment screen (with tape). Use this line for
up/down adjustment reference.
(7) Measure distance from the centerline of the
vehicle to the center of each headlamp being aligned.
Transfer measurements to screen (with tape) to each
side of vehicle centerline. Use these lines for left/
right adjustment reference.
VEHICLE PREPARATION FOR HEADLAMP
ALIGNMENT
(1) Verify headlamp dimmer switch and high beam
indicator operation.
(2) Correct defective components that could hinder
proper headlamp alignment.
(3) Verify proper tire inflation.
(4) Clean headlamp lenses.
(5) Verify that luggage area is not heavily loaded.
(6) Fuel tank should be FULL. Add 2.94 kg (6.5
lbs.) of weight over the fuel tank for each estimated
gallon of missing fuel.
HEADLAMP ALIGNMENT
A properly aimed low beam headlamp will project
top edge of high intensity pattern on screen from 50
mm (2 in.) above to 50 mm (2 in.) below headlamp
centerline. The side-to-side outboard edge of high
intensity pattern should be from 50 mm (2 in.) left to
50 mm (2 in.) right of headlamp centerline (Fig. 11).
The preferred headlamp alignment is 1(down
for the up/down adjustment and 0 for the left/
right adjustment.The high beam pattern should be
correct when the low beams are aligned properly.
To adjust low beam headlamp, rotate alignment
screws to achieve the specified aim.
Fig. 10 HEADLAMP Ð TYPICAL
1 - SEAL
2 - PUSH PIN
3 - SCREW
4 - HEADLAMP UNIT
DRLAMPS/LIGHTING - EXTERIOR 8L - 15
HEADLAMP SWITCH (Continued)

INSTALLATION
INSTALLATION
(1) Quarter twist the bulb socket into the lamp
assembly
(2) Position the lamp assembly against the fender,
using firm pressure insert the lens into the fender.
(Fig. 13)
INSTALLATION
(1) Position the tailgate marker bulb harness to
the lens and quarter twist each bulb assembly clock-
wise to seat bulb sockets.
(2) Position the tailgate marker lens to the tailgate
and install the retaining screws. (Fig. 14)
MULTI-FUNCTION SWITCH
DESCRIPTION - TURN SIGNAL SYSTEM
The multi-function switch is a resistive MUX
switch that is monitored by the Instrument Cluster.
The turn signals are actuated with the lever on
Multi-Function Switch. The signals are automatically
turned off by a canceling cam (two lobes molded to
the back of the clock spring mechanism). The cam
comes in contact with the cancel actuator on the turn
signal (multi-function) switch assembly. Either cam
Fig. 12 License Plate Lamp Panel
1 - REAR BUMPER
2 - WIRING CONNECTOR
3 - CLIP
4 - LICENSE PLATE LAMP UNIT
Fig. 13 FENDER EXTENSION AND MARKER LAMP
ASSEMBLY
1 - WIRING HARNESS
2 - MARKER LAMP
Fig. 14 Tailgate Marker Lamp Housing
1 - Nut
2 - Tailgate
3 - Bulb Harness
4 - Screw
5 - Lens
DRLAMPS/LIGHTING - EXTERIOR 8L - 17
MARKER LAMP UNIT (Continued)

lobe, pushing on the cancel actuator, returns the
switch to the OFF position.
OPERATION - TURN SIGNAL SYSTEM
The Instrument Cluster monitors the multiplexed
multifunction switch. In a turning event the Instru-
ment Cluster senses a change in the turn signal
lever and illuminates the appropriate turn signal
indicator. At the same time, the Instrument Cluster
will send a J1850 message on the PCI bus to the
Front Control Module (FCM). The FCM will respond
by activating the appropriate relay in the Power Dis-
tribution Center.
A chime will sound after the turn is completed if
vehicle has traveled a distance of approximately 1.0
mile and a speed of 15 mph, with the turn signal ON.
DIAGNOSIS AND TESTING - MULTI-FUNCTION
SWITCH
To test the turn signal, headlamp beam select and
optical horn portion of the multi-function switch:
(1) Remove the multi-function switch, refer to
Electrical, Lamps/Lighting - Exterior, Multi-Function
Switch, Removal, and Installation.
(2) Using an ohmmeter check the resistance read-
ings between multi-function switch pins. Refer to
Wiring Diagrams for proper pin numbers and the
MULTI-FUNCTION SWITCH TESTS table.
MULTI-FUNCTION SWITCH TESTS
EXTERIOR LIGHTING FUNCTIONS
SWITCH POSITION CONNECTOR PINS RESISTANCE (OHMS)
Off 1 - 2 Open
Headlamp High Beams On 1 - 2 518 - 575
Hazard 3 - 2 115 - 128
Optical Horn (Flash-to-Pass) On 1 - 2 1257 - 1397
Off 3 - 2 2643 - 2937
Turn Signal Left 3 - 2 345 - 384
Turn Signal Right 3 - 2 786 - 873
FRONT WIPER FUNCTIONS
SWITCH POSITION CONNECTOR PINS RESISTANCE (OHMS)  10%
Front Wiper Off 2 - 4 6910 - 7678
Delay 1 2 - 4 2128 - 2365
Delay 2 2 - 4 1089 - 1210
Delay 3 2 - 4 627 - 697
Delay 4 2 - 4 388 - 431
Delay 5 2 - 4 234 - 261
Front Wiper Low 2 - 4 125 - 140
Front Wiper High 2 - 4 50 - 56
Wash 1 - 2 2584 - 2871
REMOVAL
WARNING: BEFORE SERVICING THE STEERING
COLUMN THE AIRBAG SYSTEM MUST BE DIS-
ARMED. REFER TO THE ELECTRICAL RESTRAINT
SYSTEM FOR SERVICE PROCEDURES. FAILURE
TO DO SO MAY RESULT IN ACCIDENTAL DEPLOY-
MENT OF THE AIRBAG AND POSSIBLE PERSONAL
INJURY(1) Disconnect and isolate battery negative cable.
(2) Remove the steering wheel and the upper and
lower steering column shrouds. Refer to Steering,
Column, Shroud, Removal.
(3) Disconnect the wire connector from the back of
the multi-function switch.
(4) Remove the screws retaining the multi-function
switch to the steering column adapter collar (Fig. 15).
(5) Remove the multi-function switch.
8L - 18 LAMPS/LIGHTING - EXTERIORDR
MULTI-FUNCTION SWITCH (Continued)