
mission have an illuminated transmission range indi-
cator integral to the console mounted gearshift
mechanism, and controlled by the panel lamps dim-
mer circuit.
²Vanity Lamps- Available single intensity van-
ity lamps are located on each side of a covered mirror
on both the right and left sun visors, and are con-
trolled by an integral vanity mirror cover-actuated
switch on the courtesy lamp circuit.
Other components of the interior lighting system
for this model include:
²Body Control Module- The Body Control
Module (BCM) is located on the Junction Block (JB)
under the driver side outboard end of the instrument
panel. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/BODY CONTROL MODULE
- DESCRIPTION).
²Door Ajar Switches- A door ajar switch is
integral to the door latch mechanism of each front
and rear door.
²Flip-Up Glass Ajar Switch- A flip-up glass
ajar switch is integral to the flip-up glass latch mech-
anism on the top of the tailgate inner panel.
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 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 con-
trols for both the exterior and interior lighting sys-
tems. (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING
- EXTERIOR/MULTI-FUNCTION SWITCH -
DESCRIPTION).
²Tailgate Ajar Switch- A tailgate ajar switch is
integral to the latch mechanism of the tailgate.
Hard wired circuitry connects the interior 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 interior 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
The interior lighting systems can be divided into
two general classifications based upon the circuit
that controls their operation: The courtesy lamp cir-cuit, or the panel lamps dimmer circuit. Following
are paragraphs that briefly describe the operation of
each of the major interior lighting systems. The hard
wired circuits and components of the interior lighting
systems may be diagnosed and tested using conven-
tional diagnostic tools and procedures. However, con-
ventional diagnostic methods may not prove
conclusive in the diagnosis of the Body Control Mod-
ule (BCM), the ElectroMechanical Instrument Clus-
ter (EMIC), or the Programmable Communications
Interface (PCI) data bus network. The most reliable,
efficient, and accurate means to diagnose the BCM,
the EMIC, and the PCI data bus network inputs and
outputs related to the various interior lighting sys-
tems requires the use of a DRBIIItscan tool. Refer
to the appropriate diagnostic information.
COURTESY LAMP CIRCUIT Depending upon the
selected vehicle options the courtesy lamp circuit
may include the courtesy lamps located below the
instrument panel, the dome or map/reading lamps
located in the headliner near the windshield, the
cargo lamp located in the headliner near the rear
roof header, and the vanity lamps located in the sun
visors. The lamps in the courtesy lamp circuit are
provided with battery current at all times from a
fused B(+) fuse in the Junction Block (JB) through a
fused B(+) circuit. The Body Control Module (BCM)
controls the ground path for these lamps using an
internal driver through the courtesy lamp driver cir-
cuit based upon hard wired inputs from the door ajar
switches, the flip-up glass ajar switch, and the tail-
gate ajar switch. After all of the ajar switch inputs to
the BCM transition to open, the BCM will keep the
lamps illuminated for about 27 seconds, then fade
the lamps to off (theater dimming) over about three
seconds.
The BCM also provides courtesy lamp operation
based upon a resistor multiplexed input from the
interior lighting control ring on the left (lighting)
control stalk of the multi-function switch through the
headlamp switch mux circuit, and in response to cer-
tain inputs from the optional Remote Keyless Entry
(RKE) system. A resistor multiplexed courtesy lamp
defeat input from the control ring on the left (light-
ing) control stalk of the multi-function switch will
cause the BCM to override normal courtesy lamp
operation based upon inputs from all of the ajar
switches. A hard wired input from the courtesy lamp
defeat switch in the optional cargo lamp through a
rear courtesy lamp control circuit will cause the BCM
to override normal courtesy lamp operation based
upon inputs from only the flip-up glass and tailgate
ajar switches.
For those lamps on the courtesy lamp circuit with
independent switching, such as the optional reading
lamps and vanity lamps, the BCM provides a ground
KJLAMPS/LIGHTING - INTERIOR 8L - 67
LAMPS/LIGHTING - INTERIOR (Continued)

path to the switches using another internal driver
through the courtesy lamp load shed circuit. The
BCM provides a battery saver (load shedding) feature
for all courtesy lamps, which will automatically turn
these lamps off if they are left on for more than
about eight minutes with the ignition switch in the
Off position.
PANEL LAMPS DIMMER CIRCUIT The panel
lamps dimmer circuit includes the ElectroMechanical
Instrument Cluster (EMIC), heater-air conditioner
control, hazard switch and, depending upon the
selected vehicle options, ash receiver, and automatic
transmission range indicator illumination lamps. All
lamps in the panel lamps dimmer circuit are pro-
vided a path to ground at all times through a hard
wired ground circuit. These lamps illuminate based
upon inputs to the Body Control Module (BCM) from
the exterior lighting control knob and the interior
lighting control ring on the left (lighting) control
stalk of the multi-function switch. The control knob
on the left control stalk of the multi-function switch
selects the exterior lights, while the control ring
selects the panel lamps intensity (dimming) level.
When the exterior lighting is turned On, the BCM
energizes the park lamp relay and provides an elec-
tronic dimming level message to the ElectroMechani-
cal Instrument Cluster (EMIC), the radio, and the
Compass Mini-Trip Computer (CMTC) over the Pro-
grammable Communications Interface (PCI) data
bus. The energized park lamp relay provides a hard
wired battery current signal input to the EMIC on
the park lamp relay output circuit. The EMIC
responds to these inputs by supplying a 12-volt Pulse
Width Modulated (PWM) output to all of the incan-
descent lamps in the panel lamps dimmer circuit
over the fused panel lamps dimmer switch signal cir-
cuit. This shared PWM output synchronizes the
selected illumination intensity level of all of the
incandescent lamps in the panel lamps dimmer cir-
cuit.
The EMIC and the radio each use the electronic
dimming level message from the BCM to control and
synchronize the illumination intensity of their own
Vacuum Fluorescent Display (VFD), while the CMTC
uses the dimming level message to control the illumi-
nation intensity of both its VFD and its incandescent
lighting. In addition, when the control ring on the
left (lighting) control stalk of the multi-function
switch is moved to the Parade Mode detent position,
all of the VFDs are illuminated at their full intensity
levels for increased visibility when the vehicle is
driven during daylight hours with the exterior lights
turned On.DIAGNOSIS AND TESTING - LAMPS/LIGHTING
- INTERIOR
The hard wired circuits and components of the
interior lighting system may be diagnosed and tested
using conventional diagnostic tools and procedures.
However, conventional diagnostic methods may not
prove conclusive in the diagnosis of the Body Control
Module (BCM), the ElectroMechanical Instrument
Cluster (EMIC), or the Programmable Communica-
tions Interface (PCI) data bus network. The most
reliable, efficient, and accurate means to diagnose
the BCM, the EMIC, and the PCI data bus network
inputs and outputs related to the various interior
lighting systems requires the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
When diagnosing the interior lighting circuits,
remember that high generator output can burn out
bulbs rapidly and repeatedly; and, that dim or flick-
ering bulbs can be caused by low generator output or
poor battery condition. If one of these symptoms is a
problem on the vehicle being diagnosed, be certain to
diagnose and repair the battery and charging system
as required. Also keep in mind that a good ground is
necessary for proper lighting operation. If a lighting
problem is being diagnosed that involves multiple
symptoms, systems, or components the problem can
often be traced to a loose, corroded, or open ground.
For complete circuit diagrams, refer to the appropri-
ate wiring information. The wiring 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 connec-
tors, splices and grounds.
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.
8L - 68 LAMPS/LIGHTING - INTERIORKJ
LAMPS/LIGHTING - INTERIOR (Continued)

for the courtesy lamp from the connector receptacle
on the back of the lamp unit housing.
(4) Remove the courtesy lamp unit from under the
instrument panel.
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 courtesy lamp unit under the
instrument panel.
(2) Reconnect the instrument panel wire harness
connector for the courtesy lamp to the connector
receptacle on the back of the lamp unit housing.
(3) Position the courtesy lamp unit to the lower
instrument panel (Fig. 10).
(4) Install and tighten the screw that secures the
integral mounting tab of the courtesy lamp unit to
the lower instrument panel.
(5) Reconnect the battery negative cable.
DOOR AJAR SWITCH
DESCRIPTION
This vehicle has four door ajar switches, one for
each door. Each switch is concealed within and inte-
gral to its respective door latch unit. The switches
are momentary leaf contact-type units that are actu-
ated by the door latch mechanisms. A short pigtail
wire and connector on each door latch connects the
door ajar switch to the vehicle electrical system
through its respective door wire harness. The door
ajar switches cannot be adjusted or repaired and, if
faulty or damaged, the door latch unit must be
replaced. (Refer to 23 - BODY/DOOR - FRONT/
LATCH - REMOVAL) or (Refer to 23 - BODY/DOOR -
REAR/LATCH - REMOVAL).
OPERATION
The door ajar switches are actuated by the door
latch mechanisms. When a door is closed and prop-
erly latched, its door ajar switch is an open circuit.
When a door is open or only partially latched, the
door ajar switch is a closed circuit. The door ajar
switches are hard wired between a body ground and
the Body Control Module (BCM). The driver side
front door ajar switch is connected to the BCM
through a driver door ajar switch sense circuit, while
the remaining three door ajar switches are connected
to the BCM through a passenger door ajar switch
sense circuit in a parallel-series arrangement. The
BCM reads the door ajar switch status through an
internal pull-up, then uses these inputs to control
many electronic functions and features of the vehicle.
The door ajar switches can be diagnosed using con-
ventional diagnostic tools and methods; however, for
proper diagnosis of the BCM, and both the hard
wired and electronic BCM outputs affected by the
door ajar switch inputs, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
FLIP-UP GLASS AJAR SWITCH
DESCRIPTION
A flip-up glass ajar switch is standard equipment
in this vehicle. This switch is concealed within and
integral to the flip-up glass latch unit. The switch is
a momentary leaf contact-type unit that is actuated
by the flip-up glass latch mechanism. A dedicated
connector receptacle on the flip-up glass latch unit
connects the flip-up glass ajar switch to the vehicle
electrical system through the tailgate wire harness.
The flip-up glass ajar switch cannot be adjusted or
repaired and, if faulty or damaged, the flip-up glass
latch unit must be replaced. (Refer to 23 - BODY/
SWING GATE/FLIP-UP GLASS LATCH - REMOV-
AL).
OPERATION
The flip-up glass ajar switch is actuated by the
flip-up glass latch mechanism. When the flip-up glass
is closed and properly latched, the flip-up glass ajar
switch is an open circuit. When the flip-up glass is
open or only partially latched, the flip-up glass ajar
switch is a closed circuit. The flip-up glass ajar
switch is hard wired between a body ground, the
Body Control Module (BCM), and the rear wiper
motor. The output of the switch is connected to the
BCM and rear wiper motor through a flip-up glass
ajar switch sense circuit. The BCM reads the flip-up
glass ajar switch status through an internal pull-up,
then uses this input to control many electronic func-
KJLAMPS/LIGHTING - INTERIOR 8L - 77
COURTESY LAMP UNIT (Continued)

tions and features of the vehicle. The rear wiper
motor uses this input to restrict rear wiper operation
when the flip-up glass is ajar. The flip-up glass ajar
switch can be diagnosed using conventional diagnos-
tic tools and methods; however, for proper diagnosis
of the BCM, and both the hard wired and electronic
BCM outputs affected by the flip-up glass ajar switch
input, a DRBIIItscan tool is required. Refer to the
appropriate diagnostic information.
HEATER-A/C CONTROL
ILLUMINATION BULB
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 center bezel from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - REMOV-
AL).
(3) From the back of the center bezel, use a small
thin-bladed screwdriver to rotate the heater-A/C con-
trol illumination bulb holder counterclockwise about
30 degrees on the circuit board (Fig. 11).
(4) Pull the heater-A/C illumination bulb holder
and bulb unit straight out of the circuit board bulb
mounting hole.
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.
CAUTION: Always use the correct bulb size and
type for replacement. An incorrect bulb size or type
may overheat and cause damage to the lamp, the
socket and/or the lamp wiring.
(1) Align the heater-A/C control illumination bulb
holder and bulb unit with the circuit board bulb
mounting hole.
(2) Insert the heater-A/C control illumination bulb
holder and bulb unit straight into the circuit board
bulb mounting hole until it is firmly seated (Fig. 11).
(3) Using a small thin-bladed screwdriver, rotate
the heater-A/C control illumination bulb holder clock-
wise about 30 degrees on the circuit board.
(4) Reinstall the center bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - INSTAL-
LATION).
(5) Reconnect the battery negative cable.
Fig. 11 Heater-A/C Control Illumination Bulb
Remove/Install
1 - CENTER BEZEL
2 - BULB HOLDER & BULB (2)
3 - HEATER-A/C CONTROL
8L - 78 LAMPS/LIGHTING - INTERIORKJ
FLIP-UP GLASS AJAR SWITCH (Continued)

TAILGATE AJAR SWITCH
DESCRIPTION
A tailgate ajar switch is standard equipment in
this vehicle. This switch is concealed within and inte-
gral to the tailgate latch unit. The switch is a
momentary leaf contact-type unit that is actuated by
the tailgate latch mechanism. A pigtail wire harness
and connector on the tailgate latch unit connects the
tailgate ajar switch to the vehicle electrical system
through the tailgate wire harness. The tailgate ajar
switch cannot be adjusted or repaired and, if faulty
or damaged, the tailgate latch unit must be replaced.
(Refer to 23 - BODY/SWING GATE/LATCH -
REMOVAL).
OPERATION
The tailgate switch is actuated by the tailgate
latch mechanism. When the tailgate is closed and
properly latched, the tailgate ajar switch is an open
circuit. When the tailgate is open or only partially
latched, the tailgate ajar switch is a closed circuit.
The tailgate ajar switch is hard wired between a
body ground and the Body Control Module (BCM).
The output of the switch is connected to the BCM
through a tailgate ajar switch sense circuit. The
BCM reads the tailgate ajar switch status through
an internal pull-up, then uses this input to control
many electronic functions and features of the vehicle.
The tailgate ajar switch can be diagnosed using con-
ventional diagnostic tools and methods; however, for
proper diagnosis of the BCM, and both the hard
wired and electronic BCM outputs affected by the
tailgate ajar switch input, a DRBIIItscan tool is
required. Refer to the appropriate diagnostic infor-
mation.
TRANSMISSION RANGE
INDICATOR ILLUMINATION
BULB
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 center console from the floor panel
transmission tunnel. (Refer to 23 - BODY/INTERI-
OR/FLOOR CONSOLE - REMOVAL).
(3) From the left side of the vehicle, reach between
transmission range indicator and the floor panel
transmission tunnel to grasp the illumination lamp
socket (Fig. 15).
Fig. 15 Transmission Range Indicator Illumination
Bulb Remove/Install
1 - AUTOMATIC TRANSMISSION SHIFT MECHANISM
2 - ILLUMINATION LAMP SOCKET
8L - 82 LAMPS/LIGHTING - INTERIORKJ

²Trailer Tow Adapter- Vehicles equipped with
a factory-installed trailer towing package have an
adapter provided that adapts the factory-installed
heavy duty 7-way trailer tow connector to a conven-
tional 4-way light duty connector.
²Trailer Tow Connector- Vehicles equipped
with a factory-installed trailer towing package have a
heavy duty 7-way trailer tow connector installed in a
bracket on the trailer hitch receiver.
²Trailer Tow Relays- Vehicles equipped with a
factory-installed trailer towing package have a con-
nector bank containing four relays located behind the
right quarter trim panel and over the right rear
wheel housing. The four relays are used to supply
fused ignition switch output (run), brake lamps, right
turn signal, and left turn signal outputs to a trailer
through the trailer tow wiring and connectors.
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 Body
Control Module (BCM), the ElectroMechanical
Instrument Cluster (EMIC), the Powertrain Control
Module (PCM), or the Programmable Communica-
tions Interface (PCI) data bus network. The most
reliable, efficient, and accurate means to diagnose
the BCM, the EMIC, the PCM, and the PCI data bus
network inputs and outputs related to the various
exterior lighting systems requires the use of a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information.BACKUP LAMPS
The backup (or reverse) lamps have a path to
ground at all times through their connection to the
rear lighting wire harness from a take out of the rear
body wire harness with an eyelet terminal connector
that is secured by a ground screw to the base of the
right D-pillar behind the quarter trim panel. The
backup lamps receive battery current from a fused
ignition switch output (run) fuse in the Junction
Block (JB) on the back-up lamp feed circuit only
when the backup lamp switch (manual transmission),
or backup lamp switch circuit of the Transmission
Range Sensor (TRS - electronic automatic transmis-
sion) is closed by the gearshift mechanism within the
transmission.
BRAKE LAMPS
The brake (or stop) lamps have a path to ground at
all times through their connection to the rear light-
ing wire harness from a take out of the rear body
wire harness with an eyelet terminal connector that
is secured by a screw to the base of the right D-pillar
behind the quarter trim panel. The Center High
Mounted Stop Lamp (CHMSL) has a path to ground
at all times through its connection to the rear body
wire harness from a take out of the rear body wire
harness with an eyelet terminal connector that is
secured by a ground screw to the driver side D-pillar
(left side D-pillar for left-hand drive, right side D-pil-
lar for right-hand drive) behind the quarter trim
panel. The brake lamps and CHMSL receive battery
current from a fused B(+) fuse in the Junction Block
(JB) on the brake lamp switch output circuit only
when the brake lamp switch circuit of the brake
lamp switch is closed by the brake pedal arm.
DAYTIME RUNNING LAMPS
Vehicles manufactured for sale in Canada illumi-
nate the high beam filament at a reduced intensity
when the engine is running and the exterior lamps
are turned off. This feature is enabled by the Body
Control Module (BCM) and a solid state Daytime
Running Lamps (DRL) relay, which is installed in the
Junction Block (JB) and the high beam relay is omit-
ted. When the BCM monitors an engine speed signal
of greater than 450 RPM and the status of the exte-
rior lighting switch input from the multi-function
switch is Off, the BCM duty cycles the DRL relay to
produce illumination of the headlamp high beam fil-
aments at a reduced intensity. The BCM also pro-
vides normal headlamp high beam operation through
the DRL relay on vehicles so equipped. When the
DRL relay is energized, it provides battery current
from a fused B(+) fuse in the JB to the headlamp
high beam filament through the DRL relay output
circuit.
KJLAMPS8Ls-5
LAMPS/LIGHTING - EXTERIOR (Continued)

move the headlamps to the selected position 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 compo-
nents operate on battery current received through
the fused park lamp relay output circuit so that the
system will only operate when the exterior lighting is
turned on.
PARK LAMPS
The park lamps system includes the Body Control
Module (BCM), a park lamp relay installed in the
Junction Block (JB), and the exterior lighting switch
integral to the left (lighting) control stalk of the
multi-function switch. The front park lamp and side
marker or, if equipped, the front position lamp bulbs
each have a path to ground at all times through their
connections to the grille opening reinforcement wire
harness from two take outs of the headlamp and
dash wire harness with eyelet terminal connectors
that are secured by ground screws to the left inner
fender shield in the engine compartment. The rear
park lamp bulbs and license plate lamp have a path
to ground at all times through their connection to the
rear lighting wire harness from a take out of the rear
body wire harness with an eyelet terminal connector
that is secured by a ground screw to the base of the
right D-pillar behind the quarter trim panel. The
BCM controls the park lamp operation by monitoring
the exterior lighting switch inputs from the multi-
function switch, then energizing or de-energizing the
control coil of the park lamp relay. When the park
lamp relay is energized, it provides battery current
from a fused B(+) fuse in the Power Distribution
Center (PDC) through a park lamp relay output cir-
cuit and a separate fuse in the JB through a fused
park lamp relay output circuit to the appropriate
lamp bulb filaments. The BCM provides a battery
saver (load shedding) feature for the park lamps,
which will turn these lamps off if they are left on for
more than about eight minutes with the ignition
switch in the Off position.
REAR FOG LAMPS
Rear fog lamps are installed on vehicles manufac-
tured for certain markets where they are required.
The rear fog lamp system includes a premium Body
Control Module (BCM), a rear fog lamp relay
installed in the Junction Block (JB), and a rear fog
lamp switch integral to the left (lighting) control
stalk of the multi-function switch. The rear fog lamps
have a path to ground at all times through their con-
nection to the rear lighting wire harness from a take
out of the rear body wire harness with an eyelet ter-
minal connector that is secured by a ground screw to
the base of the right D-pillar behind the quarter trimpanel. The BCM controls rear fog lamp operation by
monitoring the exterior lighting switch input from
the multi-function switch, then energizing or de-ener-
gizing the rear fog lamp relay control coil; and, by
sending the appropriate electronic message to the
instrument cluster over the Programmable Commu-
nications Interface (PCI) data bus to turn the rear
fog lamp indicator on or off. When the rear fog lamp
relay is energized, it provides battery current from a
fused B(+) fuse in the JB to the rear fog lamps
through the rear fog lamp relay output circuit. The
BCM provides a battery saver (load shedding) feature
for the rear fog lamps, which will turn these lamps
off if they are left on for more than about eight min-
utes with the ignition switch in the Off position.
TURN SIGNAL LAMPS
When the left control stalk of the multi-function
switch is moved up (right turn) or down (left turn),
the turn signal system is activated causing the
selected right or left turn signal indicator, and right
or left turn signal lamps to flash on and off. When
the turn signal system is activated, the circuitry
within the turn signal switch and the hazard switch/
electronic combination flasher unit will repeatedly
energize and de-energize one of two internal relays
that switch battery current from a fused ignition
switch output (run) fuse in the Junction Block (JB) to
the right side or left side turn signal indicators and
turn signal lamps through the right or left turn sig-
nal circuits. The ElectroMechanical Instrument Clus-
ter (EMIC) chime tone generator will generate an
audible turn signal cancel warning each time the
vehicle is driven for a distance of about 3.2 kilome-
ters (about two miles) with a turn signal indicator
flashing. The EMIC uses Programmable Communica-
tions Interface (PCI) data bus distance messages
from the Powertrain Control Module (PCM) and a
hard wired input from the turn signal switch cir-
cuitry of the multi-function switch to determine when
to sound the turn signal cancel warning.
DIAGNOSIS AND TESTING - LAMPS/LIGHTING
- EXTERIOR
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 Body
Control Module (BCM), the ElectroMechanical
Instrument Cluster (EMIC), the Powertrain Control
Module (PCM), or the Programmable Communica-
tions Interface (PCI) data bus network. The most
reliable, efficient, and accurate means to diagnose
the BCM, the EMIC, the PCM, and the PCI data bus
network inputs and outputs related to the various
KJLAMPS8Ls-7
LAMPS/LIGHTING - EXTERIOR (Continued)

²Headlamp Optical Horn- The left (lighting)
control stalk of the multi-function switch is pulled
towards the steering wheel to just before a detent, to
momentarily activate the headlamp optical horn fea-
ture. The high beams will remain illuminated until
the control stalk is released. The multi-function
switch provides a ground output on a high beam
relay control circuit to energize the headlamp high
beam relay (Daytime Running Lamp relay in Cana-
dian vehicles) in the Junction Block (JB) as required.
²Interior Lamps Defeat- The control ring on
the multi-function switch left (lighting) control stalk
is rotated to a full rearward (clockwise) detent to
defeat the illumination of all interior courtesy lamps.
The multi-function switch provides a resistor multi-
plexed output to the Body Control Module (BCM) on
a panel lamps dimmer switch mux circuit, and the
BCM responds by de-energizing its internal courtesy
lamp driver circuit.
²Interior Lamps On- The control ring on the
multi-function switch left (lighting) control stalk is
rotated to a full forward (counterclockwise) detent to
illuminate all interior courtesy lamps. The multi-
function switch provides a resistor multiplexed out-
put to the Body Control Module (BCM) on a panel
lamps dimmer switch mux circuit, and the BCM
responds by energizing its internal courtesy lamp
driver circuit.
²Panel Lamps Dimming- The control ring on
the multi-function switch left (lighting) control stalk
is rotated to one of six minor intermediate detents to
simultaneously select the desired illumination inten-
sity of all adjustable instrument panel and instru-
ment cluster lighting. The control ring is rotated
rearward (clockwise) to dim, or forward (counter-
clockwise) to brighten. The multi-function switch pro-
vides a resistor multiplexed output to the Body
Control Module (BCM) on a panel lamps dimmer
switch mux circuit, and the BCM responds by send-
ing an electronic panel lamps dimming level message
to the ElectroMechanical Instrument Cluster (EMIC)
over the Programmable Communications Interface
(PCI) data bus. The EMIC electronic circuitry then
provides the proper PWM output to the cluster illu-
mination lamps and the VFD on the EMIC circuit
board, then provides a matching PWM output on the
hard wired fused panel lamps dimmer switch signal
circuit.
²Parade Mode- The control ring on the multi-
function switch left (lighting) control stalk is rotated
to an intermediate detent that is one detent rear-
ward (clockwise) from the full forward (counterclock-
wise) detent to select the Parade mode. The multi-
function switch provides a resistor multiplexed
output to the Body Control Module (BCM) on a panel
lamps dimmer switch mux circuit, and the BCMresponds by sending an electronic panel lamps dim-
ming level message to the ElectroMechanical Instru-
ment Cluster (EMIC) over the Programmable
Communications Interface (PCI) data bus. The EMIC
electronic circuitry then provides the proper PWM
output to the cluster illumination lamps and the
VFD on the EMIC circuit board, then provides a
matching PWM output on the hard wired fused panel
lamps dimmer switch signal circuit to illuminate all
lamps at full (daylight) intensity with the exterior
lamps turned On.
²Park Lamps- The control knob on the end of
the multi-function switch left (lighting) control stalk
is rotated forward (counterclockwise) to its first
detent from the Off position to activate the park
lamps. The multi-function switch provides a resistor
multiplexed output to the Body Control Module
(BCM) on a headlamp switch sense circuit, and the
BCM responds by energizing or de-energizing the
park lamp relay in the Junction Block (JB) as
required.
²Rear Fog Lamps- For vehicles so equipped,
the control knob on the end of the multi-function
switch left (lighting) control stalk is rotated forward
(counterclockwise) to its third detent position to acti-
vate the rear fog lamps. The multi-function switch
provides a resistor multiplexed output to the Body
Control Module (BCM) on a headlamp switch sense
circuit, and the BCM responds by energizing or de-
energizing the rear fog lamp relay in the Junction
Block (JB) as required. Rear fog lamps are optional
only for vehicles manufactured for certain markets,
where they are required.
²Turn Signal Control- The left (lighting) con-
trol stalk of the multi-function switch is moved
upward to activate the right turn signal circuitry,
and, downward to activate the left turn signal cir-
cuitry. The turn signal switch has a detent position
in each direction that provides turn signals with
automatic cancellation, and an intermediate, momen-
tary position in each direction that provides turn sig-
nals only until the left multi-function switch control
stalk is released. When the control stalk is moved to
a turn signal switch detent position, the cancel
actuator extends toward the center of the steering
column. A turn signal cancel cam that is integral to
the clockspring rotates with the steering wheel and
the cam lobes contact the cancel actuator when it is
extended from the left multi-function switch. When
the steering wheel is rotated during a turning
maneuver, one of the two turn signal cancel cam
lobes will contact the turn signal cancel actuator. The
cancel actuator latches against the cancel cam rota-
tion in the direction opposite that which is signaled.
In other words, if the left turn signal detent is
selected, the lobes of the cancel cam will ratchet past
KJLAMPS8Ls-49
MULTI-FUNCTION SWITCH (Continued)