2002 JEEP LIBERTY tail light

²Normally Open Terminal- The normally open
terminal (87) is connected to the headlamp high
beam filaments through the high beam relay output
circuit and provides battery current to the headlamp
high beams whenever the relay is energized.
²Normally Closed Terminal- The normally
closed terminal (87A) is not connected in this appli-
cation.
The headlamp high beam relay can be diagnosed
using conventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - HEADLAMP HIGH
BEAM RELAY
The headlamp high beam relay (Fig. 29) is located
in the Junction Block (JB) on the driver side out-
board end of the instrument panel. Refer to the
appropriate wiring information. The wiring informa-
tion includes wiring diagrams, proper wire and con-
nector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, 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.
(1) Remove the headlamp high beam relay from
the JB. (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR/HEADLAMP HIGH BEAM RELAY
- REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(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 DRBIIItscan 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 end cap from the driver side out-
board end of the instrument panel. (Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL END CAP - REMOVAL).
(3) Remove the headlamp high beam relay by
grasping it firmly and pulling it straight out from the
receptacle in the Junction Block (JB) (Fig. 30).
Fig. 29 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
8L - 34 LAMPS/LIGHTING - EXTERIORKJ
HEADLAMP HIGH BEAM RELAY (Continued)

²Coil Battery Terminal- The coil battery ter-
minal (86) is connected to a control output of the
Body Control Module (BCM) through a low beam
relay control circuit. The BCM controls headlamp low
beam operation by controlling a ground path through
this circuit.
²Normally Open Terminal- The normally open
terminal (87) is connected to the headlamp low beam
filaments through the low beam relay output circuit
and provides battery current to the headlamp low
beams whenever the relay is energized.
²Normally Closed Terminal- The normally
closed terminal (87A) is not connected in this appli-
cation.
The headlamp low beam relay can be diagnosed
using conventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - HEADLAMP LOW
BEAM RELAY
The headlamp low beam relay (Fig. 38) is located
in the Junction Block (JB) under the driver side out-
board end of the instrument panel. Refer to the
appropriate wiring information. The wiring informa-
tion includes wiring diagrams, proper wire and con-
nector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, 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.
(1) Remove the headlamp low beam relay from the
JB. (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/HEADLAMP LOW BEAM RELAY -
REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.(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.
Fig. 38 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
8L - 40 LAMPS/LIGHTING - EXTERIORKJ
HEADLAMP LOW BEAM RELAY (Continued)

(7) Pull the bulb straight out of the license plate
lamp unit socket.
INSTALLATION
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.
NORTH AMERICA
(1) Align the base of the bulb with the receptacle
in the license plate lamp unit socket.
(2) Push the bulb straight into the license plate
lamp unit socket until it is firmly seated.
(3) Reach through the opening in the rear bumper
fascia between the license plate and the lamp to
align the socket and bulb with the socket opening on
the back of the lamp unit housing (Fig. 45).
(4) Push the socket and bulb straight into the
license plate lamp unit housing until it is firmly
seated.
(5) Reconnect the battery negative cable.
REST-OF-WORLD
(1) Align the base of the bulb with the receptacle
in the license plate lamp unit socket.
(2) Push the bulb straight into the license plate
lamp unit socket until it is firmly seated.
(3) Align the socket and bulb with the socket open-
ing on the top of the license plate lamp unit housing
(Fig. 47).(4) Push the socket and bulb straight into the
license plate lamp unit housing until it is firmly
seated.
(5) Rotate the socket on the top of the license plate
lamp unit housing clockwise about 30 degrees.
(6) Swing the license plate bracket back against
the spare tire (Fig. 46).
(7) Lift up the bottom of the license mounting
plate far enough to install and tighten the two
screws that secure the license plate bracket to the
special lug nuts on the spare tire. Tighten the screws
to 28 N´m (21 ft. lbs.).
(8) Lower the bottom of the license mounting plate
and, using hand pressure, snap it into place on the
license plate bracket.
(9) Reconnect the battery negative cable.
LICENSE PLATE LAMP UNIT
REMOVAL
NORTH AMERICA
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the two screws that secure the license
plate lamp unit to the rear bumper fascia (Fig. 48).
(3) Pull the license plate lamp unit down and out
through the mounting hole in the rear bumper fascia
far enough to access and disconnect the wire harness
connector for the lamp socket pigtail wire.
(4) Remove the license plate lamp unit from the
rear bumper fascia.
Fig. 47 License Plate Lamp Bulb Remove/Install -
Rest-Of-World
1 - LAMP UNIT (2)
2 - LICENSE PLATE BRACKET
3 - SCREW (4)
4 - BULB & SOCKET (2)
Fig. 48 License Plate Lamp Unit Remove/Install
1 - REAR BUMPER FASCIA
2 - LICENSE PLATE LAMP UNIT
3 - SCREW (2)
KJLAMPS/LIGHTING - EXTERIOR 8L - 45
LICENSE PLATE LAMP BULB (Continued)

REST-OF-WORLD
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the bulb and socket unit from the
license plate lamp unit housing that is being
removed. (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR/LICENSE PLATE LAMP BULB -
REMOVAL - REST-OF-WORLD).
(3) Remove the two screws that secure the license
plate lamp unit to the back of the license plate
bracket (Fig. 49).
(1) Remove the license plate lamp unit from the
back of the license plate bracket.
INSTALLATION
NORTH AMERICA
(1) Position the license plate lamp unit to the rear
bumper fascia.
(2) Reconnect the wire harness connector for the
license plate lamp unit to the lamp socket pigtail
wire.
(3) Position the license plate lamp unit into the
mounting hole in the rear bumper fascia (Fig. 48).
(4) Install and tighten the two screws that secure
the license plate lamp unit housing to the rear
bumper fascia. Tighten the screws to 2 N´m (20 in.
lbs.).
(5) Reconnect the battery negative cable.
REST-OF-WORLD
(1) Position the license plate lamp unit onto the
back of the license plate bracket (Fig. 49).(2) Install and tighten the two screws that secure
the license plate lamp unit to the back of the license
plate bracket. Tighten the screws to 2 N´m (20 in.
lbs.).
(3) Reinstall the bulb and socket unit into the
license plate lamp unit housing that is being
replaced. (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR/LICENSE PLATE LAMP BULB -
INSTALLATION - REST-OF-WORLD).
(4) Reconnect the battery negative cable.
MULTI-FUNCTION SWITCH
DESCRIPTION
The multi-function switch is located on the steering
column, just below the steering wheel (Fig. 50). The
only visible components of the multi-function switch
are two levers, or control stalks that extend through
dedicated openings in each side of the steering col-
umn shrouds. The remainder of the switch, its
mounting provisions, and its electrical connections
are all concealed beneath the steering column
shrouds. The switch housing and controls are con-
structed of molded black plastic. A saddle-like forma-
tion in the center of the multi-function switch
housing straddles the steering column tube just
below the column lock housing, and two posts inte-
gral to the lower surface of the switch housing
engage two holes on the forward-facing side of the
lock housing. Two integral ledge-like locating tabs
near the top of the rearward facing switch housing
surface are supported and located by two upright
stanchions that extend upward from the top of the
lock housing. Also on the rearward facing switch
housing surface near the center, an integral ledge-
like mounting tab rests on a similar ledge-like tab
that extends from each side of the steering column
lock housing. When the steering column shrouds are
installed on the column, the switch mounting tabs
are clamped along with the mounting tabs of the
clockspring between the integral mounting stan-
chions of the upper shroud and the lock housing tabs,
and are secured to the steering column lock housing
by the same two screws that secure the two shroud
halves to each other and the column.
There are several versions of the multi-function
switch to support both optional equipment and equip-
ment that is required only in certain markets. Each
multi-function switch control stalk has both white
nomenclature and International Control and Display
Symbol graphics applied to it, which clearly identify
its many functions. Each control stalk has a control
knob on its end with a flattened face to allow it to be
easily rotated. On vehicles equipped with optional
front fog lamps, the knob on the end of left control
Fig. 49 License Plate Lamp Bulb Remove/Install -
Rest-Of-World
1 - LAMP UNIT (2)
2 - LICENSE PLATE BRACKET
3 - SCREW (4)
4 - BULB & SOCKET (2)
8L - 46 LAMPS/LIGHTING - EXTERIORKJ
LICENSE PLATE LAMP UNIT (Continued)

stalk can also be pulled outward to select those
lamps. Each control stalk also features a knurled
control ring located just below the control knob. The
left control stalk is dedicated to providing driver con-
trols for the interior and exterior lighting systems,
while the right control stalk is dedicated to providing
driver controls for the front and rear wiper systems.
Two integral connector receptacles on the forward
facing surface of the multi-function switch housing
connect the switch two the vehicle electrical system
through two take outs and connectors of the instru-
ment panel wire harness. The left connector recepta-
cle contains nine terminal pins for the lighting
control circuits of the switch, while the right connec-
tor receptacle contains six terminal pins for the
wiper control circuits of the switch. The multi-func-
tion switch cannot be adjusted or repaired and, if
faulty or damaged, it must be replaced.
LEFT CONTROL STALK The left (lighting) control
stalk of the multi-function switch supports the fol-
lowing functions and features:
²Front Fog Lamps- For vehicles so equipped,
the internal circuitry and hardware of the multi-
function switch left (lighting) control stalk provide
detent switching for the optional front fog lamps.
²Headlamps- The internal circuitry and hard-
ware of the multi-function switch left (lighting) con-
trol stalk provide detent switching for the
headlamps.²Headlamp Beam Selection- The internal cir-
cuitry and hardware of the multi-function switch left
(lighting) control stalk provide detent switching for
selection of the headlamp high or low beams.
²Headlamp Optical Horn- The internal cir-
cuitry and hardware of the multi-function switch left
(lighting) control stalk includes momentary switching
of the headlamp high beam circuits to provide an
optical horn feature (sometimes referred to as flash-
to-pass), which allows the vehicle operator to momen-
tarily flash the headlamp high beams as an optical
signalling device.
²Interior Lamps Defeat- The internal circuitry
and hardware of the multi-function switch left (light-
ing) control stalk provide detent switching to defeat
the illumination of all interior courtesy lamps when a
door, the rear flip-up glass, or the tailgate are
opened.
²Interior Lamps On- The internal circuitry and
hardware of the multi-function switch left (lighting)
control stalk provide detent switching to simulta-
neously illuminate all interior courtesy lamps.
²Panel Lamps Dimming- The internal cir-
cuitry and hardware of the multi-function switch left
(lighting) control stalk provide simultaneous adjust-
able control of the illumination intensity of all instru-
ment panel lighting at one of six available
illumination intensity levels.
²Parade Mode- The internal circuitry and hard-
ware of the multi-function switch left (lighting) con-
Fig. 50 Multi-Function Switch
1 - MULTI-FUNCTION SWITCH
2 - RIGHT (WIPER) CONTROL STALK
3 - LEFT (LIGHTING) CONTROL STALK
4 - TURN SIGNAL CANCEL ACTUATOR
5 - RIGHT (WIPER) CONTROL KNOB6 - RIGHT (WIPER) CONTROL RING
7 - LEFT (LIGHTING) CONTROL RING
8 - LEFT (LIGHTING) CONTROL KNOB
KJLAMPS/LIGHTING - EXTERIOR 8L - 47
MULTI-FUNCTION SWITCH (Continued)

tor as the steering wheel rotates to the right and
returns to center, which will cancel the turn signal
event and release the control stalk from the detent so
it returns to the neutral Off position. When a turn
signal is activated, the multi-function switch provides
a ground output on a right or left turn switch sense
circuit to the combination flasher circuitry within the
hazard switch, and the combination flasher flashes
the turn signal lamps.
RIGHT CONTROL STALK The right (wiper) con-
trol stalk of the multi-function switch operates as fol-
lows:
²Continuous Front Wipe Modes- The control
knob on the end of the multi-function switch right
(wiper) control stalk is rotated to an intermediate
detent that is one detent rearward (counterclockwise)
from the full forward (clockwise) detent to select the
low speed continuous front wiper mode, or to its full
forward (clockwise) detent to select the high speed
continuous front wiper mode. The multi-function
switch provides a resistor multiplexed output to the
Body Control Module (BCM) on a front wiper switch
mux circuit, and the BCM responds by energizing the
wiper on/off relay in the Power Distribution Center
(PDC) for the front low speed continuous wipe mode,
or the wiper on/off relay and the wiper high/low relay
in the PDC for the front high speed continuous wipe
mode as required.
²Continuous Rear Wipe Mode- The control
ring on the multi-function switch right (wiper) con-
trol stalk is rotated to the most forward (clockwise)
detent to select the continuous rear wiper mode. The
multi-function switch provides a battery current out-
put to the rear wiper motor on a rear wiper on driver
circuit to signal the rear wiper motor to operate in
the continuous wipe mode.
²Front Washer Mode- The right (wiper) control
stalk of the multi-function switch is pulled towards
the steering wheel to momentarily activate the
washer pump in the front washer mode. The washer
pump will continue to operate in the front washer
mode until the control stalk is released. The multi-
function switch provides a ground output on a
washer pump sense circuit, and battery current on a
washer pump driver circuit to energize the washer
pump in the front washer mode.
²Front Wiper Mist Mode- The right (wiper)
control stalk of the multi-function switch is pushed
towards the floor to momentarily activate the front
wiper motor in the mist mode. The front wiper motor
will continue to operate in the mist mode until the
control stalk is released. The multi-function switch
provides a resistor multiplexed output to the Body
Control Module (BCM) on a front wiper switch mux
circuit, and the BCM responds by energizing the
wiper on/off relay in the Power Distribution Center(PDC) to operate the front wiper motor momentarily
at low speed to provide the front wiper mist mode.
²Intermittent Front Wipe Mode- The control
knob on the end of the multi-function switch right
(wiper) control stalk is rotated to one of five minor
intermediate detents to select the desired intermit-
tent front wipe delay interval. The control knob is
rotated rearward (counterclockwise) to increase the
delay, or forward (clockwise) to decrease the delay.
The multi-function switch provides a resistor multi-
plexed output to the Body Control Module (BCM) on
a front wiper switch mux circuit, and the BCM
responds by energizing the wiper on/off relay in the
Power Distribution Center (PDC) to operate the front
wiper motor at the selected delay intervals.
²Intermittent Rear Wipe Mode- The control
ring on the multi-function switch right (wiper) con-
trol stalk is rotated to the center detent to select the
intermittent rear wiper mode. The multi-function
switch provides a battery current output to the rear
wiper motor on a rear wiper intermittent driver cir-
cuit to signal the rear wiper motor to operate in the
intermittent wipe mode.
²Rear Washer Mode- The control ring on the
multi-function switch right (wiper) control stalk is
rotated to either the full forward (clockwise) or full
rearward (counterclockwise) momentary positions to
activate the washer pump in the rear washer mode.
The washer pump will continue to operate in the rear
washer mode until the control ring is released. The
multi-function switch provides a ground output on a
washer pump driver circuit, and battery current on a
washer pump sense circuit to energize the washer
pump in the rear washer mode.
DIAGNOSIS AND TESTING - MULTI-FUNCTION
SWITCH
Refer to the appropriate 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 connectors, splices and grounds.
8L - 50 LAMPS/LIGHTING - EXTERIORKJ
MULTI-FUNCTION SWITCH (Continued)

driver side instrument panel end bracket near the
Junction Block (JB).
The park lamp relay can be diagnosed using con-
ventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - PARK LAMP
RELAY
The park lamp relay (Fig. 54) is located in the
Junction Block (JB) under the driver side outboard
end of the instrument panel. Refer to the appropriate
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 connectors, 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.
(1) Remove the park lamp relay from the JB.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/PARK LAMP RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(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 steering column opening cover
from the instrument panel. (Refer to 23 - BODY/IN-
STRUMENT PANEL/STEERING COLUMN OPEN-
ING COVER - REMOVAL).
(3) Remove the park lamp relay by grasping it
firmly and pulling it straight out from the receptacle
in the Junction Block (JB) (Fig. 55).
Fig. 54 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
KJLAMPS/LIGHTING - EXTERIOR 8L - 55
PARK LAMP RELAY (Continued)

OPERATION
The rear fog lamp relay is an electromechanical
switch that uses a low current input from the Body
Control Module (BCM) to control a high current out-
put to the rear fog lamps. The movable common feed
contact point is held against the fixed normally
closed contact point by spring pressure. When the
relay coil is energized, an electromagnetic field is
produced by the coil windings. This electromagnetic
field draws the movable relay contact point away
from the fixed normally closed contact point, and
holds it against the fixed normally open contact
point. When the relay coil is de-energized, spring
pressure returns the movable contact point back
against the fixed normally closed contact point. A
resistor is connected in parallel with the relay coil in
the relay, and helps to dissipate voltage spikes and
electromagnetic interference that can be generated as
the electromagnetic field of the relay coil collapses.
The rear fog lamp relay terminals are connected to
the vehicle electrical system through a connector
receptacle in the Junction Block (JB). The inputs and
outputs of the rear fog lamp relay include:
²Common Feed Terminal- The common feed
terminal (30) receives battery current at all times
from a fuse in the JB through a fused B(+) circuit.
²Coil Ground Terminal- The coil ground termi-
nal (85) is connected to a control output of the pre-
mium Body Control Module (BCM) through a rear
fog lamp relay control circuit. The BCM controls rear
fog lamp operation by controlling a ground path
through this circuit.
²Coil Battery Terminal- The coil battery ter-
minal (86) receives battery current at all times from
a fuse in the JB through a fused B(+) circuit.
²Normally Open Terminal- The normally open
terminal (87) is connected to the rear fog lamps
through a rear fog lamp relay output circuit and pro-
vides battery current to the rear fog lamps whenever
the relay is energized.
²Normally Closed Terminal- The normally
closed terminal (87A) is not connected in this appli-
cation.
The rear fog lamp relay can be diagnosed using
conventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - REAR FOG LAMP
RELAY
The rear fog lamp relay (Fig. 57) is located in the
Junction Block (JB) under the driver side outboard
end of the instrument panel. Refer to the appropriate
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 locationviews for the various wire harness connectors, 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.
(1) Remove the rear fog lamp relay from the JB.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/REAR FOG LAMP RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(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
Fig. 57 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
KJLAMPS/LIGHTING - EXTERIOR 8L - 57
REAR FOG LAMP RELAY (Continued)