Brake light JEEP LIBERTY 2002 KJ / 1.G Owner's Manual

BRAKES
TABLE OF CONTENTS
page page
POWER BRAKE BOOSTER
REMOVAL - RHD........................1INSTALLATION - RHD.....................1
POWER BRAKE BOOSTER
REMOVAL - RHD
(1) Remove the air box (Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER ELEMENT -
REMOVAL).
(2) Relocate the cruise control servo to gain access
to the booster for removal.
(3) Remove the brake lines from the master cylin-
der.
(4) Remove the master cylinder (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/MASTER
CYLINDER - REMOVAL).
(5) Disconnect vacuum hose from booster check
valve.
(6) Remove knee blocker under the steering colum-
n,(Refer to 23 - BODY/INSTRUMENT PANEL/KNEE
BLOCKER - REMOVAL).
(7) Remove the brake light switch.(Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - REMOVAL)
(8) Remove retaining clip that secures booster
push rod to brake pedal (Fig. 1).
(9) Remove nuts attaching booster to the dash
panel (Fig. 2).(10) In engine compartment, slide booster studs
out of dash panel, tilt booster upward, and remove
booster from engine compartment.
INSTALLATION - RHD
(1) Align and position booster on the dash panel.
(2) Install booster mounting nuts. Tighten nuts
just enough to hold booster in place.
(3) Slide booster push rod onto the brake pedal.
Then secure push rod to pedal pin with retaining
clip.
NOTE: Lubricate the pedal pin with Mopar multi-
mileage grease before installation.
(4) Tighten booster mounting nuts to 39 N´m (29
ft. lbs.).
(5) Install the brake light switch.
(6) Install the knee blocker,(Refer to 23 - BODY/
INSTRUMENT PANEL/KNEE BLOCKER - INSTAL-
LATION).
(7) If original master cylinder is being installed,
check condition of seal at rear of master cylinder.
Replace seal if cut, or torn.
(8) Clean cylinder mounting surface of brake
booster. Use shop towel wetted with brake cleaner for
Fig. 1 BOOSTER PUSH ROD
1 - BRAKE PEDAL
2 - BOOSTER ROD
Fig. 2 BOOSTER MOUNTING
1 - BRAKE BOOSTER
KJBRAKES 5s - 1

The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
OPERATION - HOSE CLAMPS
The spring type hose clamp applies constant ten-
sion on a hose connection. To remove a spring type
hose clamp, only use constant tension clamp pliers
designed to compress the hose clamp.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ON-BOARD
DIAGNOSTICS (OBD)
COOLING SYSTEM RELATED DIAGNOSTICS
The powertrain control module (PCM) has been
programmed to monitor certain cooling system com-
ponents:
²If the engine has remained cool for too long a
period, such as with a stuck open thermostat, a Diag-
nostic Trouble Code (DTC) can be set.
²If an open or shorted condition has developed in
the relay circuit controlling the electric radiator fan,
a Diagnostic Trouble Code (DTC) can be set.
If the problem is sensed in a monitored circuit
often enough to indicated an actual problem, a DTC
is stored. The DTC will be stored in the PCM mem-
ory for eventual display to the service technician.
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ACCESSING DIAGNOSTIC TROUBLE CODES
To read DTC's and to obtain cooling system data,
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ERASING TROUBLE CODES
After the problem has been repaired, use the DRB
scan tool to erase a DTC. Refer to the appropriate
Powertrain Diagnostic Procedures service informa-
tion for operation of the DRB scan tool.
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS
ENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the com-
plaint. Abnormal loads on the cooling system such as
the following may be the cause:
²PROLONGED IDLE
²VERY HIGH AMBIENT TEMPERATURE
²SLIGHT TAIL WIND AT IDLE
²SLOW TRAFFIC
²TRAFFIC JAMS
²HIGH SPEED
²STEEP GRADES
Driving techniques that avoid overheating are:
²Idle with A/C off when temperature gauge is at
end of normal range.
(1) TRAILER TOWING:
Consult Trailer Towing section of owners manual.
Do not exceed limits.
(2) RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect cooling system.
This may be:
²Engine adjustments (incorrect timing)
²Slipping engine accessory drive belt(s)
²Brakes (possibly dragging)
²Changed parts. Incorrect water pump, or pump
rotating in wrong direction due to belt not correctly
routed
²Reconditioned radiator or cooling system refill-
ing (possibly under filled or air trapped in system).
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, refer to following Cooling System Diagnosis
charts.
These charts are to be used as a quick-reference
only. Refer to the group text for information.
Fig. 2 Spring Clamp Size Location
1 - SPRING CLAMP SIZE LOCATION
KJCOOLING 7 - 3
COOLING (Continued)

OPERATION
OPERATION - COOLING SYSTEM
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible. It also
maintains normal operating temperature and pre-
vents overheating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
OPERATION - HOSE CLAMPS
The spring type hose clamp applies constant ten-
sion on a hose connection. To remove a spring type
hose clamp, only use constant tension clamp pliers
designed to compress the hose clamp.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ON-BOARD
DIAGNOSTICS (OBD)
COOLING SYSTEM RELATED DIAGNOSTICS
The powertrain control module (PCM) has been
programmed to monitor certain cooling system com-
ponents:
²If the engine has remained cool for too long a
period, such as with a stuck open thermostat, a Diag-
nostic Trouble Code (DTC) can be set.
²If an open or shorted condition has developed in
the relay circuit controlling the electric radiator fan,
a Diagnostic Trouble Code (DTC) can be set.
If the problem is sensed in a monitored circuit
often enough to indicated an actual problem, a DTC
is stored. The DTC will be stored in the PCM mem-
ory for eventual display to the service technician.
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ACCESSING DIAGNOSTIC TROUBLE CODES
To read DTC's and to obtain cooling system data,
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ERASING TROUBLE CODES
After the problem has been repaired, use the DRB
scan tool to erase a DTC. Refer to the appropriate
Powertrain Diagnostic Procedures service informa-
tion for operation of the DRB scan tool.
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS
ENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the com-
plaint. Abnormal loads on the cooling system such as
the following may be the cause:
²PROLONGED IDLE
²VERY HIGH AMBIENT TEMPERATURE
²SLIGHT TAIL WIND AT IDLE
²SLOW TRAFFIC
²TRAFFIC JAMS
²HIGH SPEED
²STEEP GRADES
Driving techniques that avoid overheating are:
²Idle with A/C off when temperature gauge is at
end of normal range.
(1) TRAILER TOWING:
Consult Trailer Towing section of owners manual.
Do not exceed limits.
(2) RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect cooling system.
This may be:
²Engine adjustments (incorrect timing)
²Slipping engine accessory drive belt(s)
²Brakes (possibly dragging)
²Changed parts. Incorrect water pump, or pump
rotating in wrong direction due to belt not correctly
routed
²Reconditioned radiator or cooling system refill-
ing (possibly under filled or air trapped in system).
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, refer to following Cooling System Diagnosis
charts.
These charts are to be used as a quick-reference
only. Refer to the group text for information.
DIAGNOSIS AND TESTING - COOLING SYSTEM
LEAKS
ULTRAVIOLET LIGHT METHOD
A leak detection additive is available through the
parts department that can be added to cooling sys-
tem. The additive is highly visible under ultraviolet
light (black light). Pour one ounce of additive into
cooling system. Place heater control unit in HEAT
position. Start and operate engine until radiator
upper hose is warm to touch. Aim the commercially
available black light tool at components to be
checked. If leaks are present, black light will cause
additive to glow a bright green color.
7s - 2 COOLING - 2.4LKJ
COOLING - 2.4L (Continued)

²Fog Lamp Control- The premium BCM pro-
vides fog lamp control for front fog lamps (optional),
and rear fog lamps (in required markets only).
²Front Wiper System Status- The BCM moni-
tors the status of the front wiper motor park switch.
²Fuel Economy and Distance to Empty Cal-
culations- The BCM calculates and transmits the
fuel economy and Distance To Empty (DTE) data.
²Headlamp Time Delay- The BCM provides a
headlamp time delay feature with the ignition switch
in the Off position.
²Heated Rear Glass Control- The BCM pro-
vides control and timer functions for the heated rear
glass feature and transmits the system status.
²Ignition On/Off Timer- The BCM monitors
and transmits the elapsed ignition On timer data
and monitors the ignition Off time.
²Ignition Switch Position Status- The BCM
monitors and transmits the status of the ignition
switch.
²Instrument Panel Dimming- The BCM mon-
itors and transmits the selected illumination inten-
sity level of the panel lamps dimmer switch.
²Interior Lamp Load Shedding- The BCM
provides a battery saver feature which will automat-
ically turn off all interior lamps that remain on after
a timed interval.
²Interior Lighting Control- The BCM moni-
tors inputs from the interior lighting switch, the door
ajar switches, the flip-up glass ajar switch, the tail-
gate ajar switch, the cargo lamp switch, the reading
lamp switches, and the Remote Keyless Entry (RKE)
module to provide courtesy lamp control. This
includes support for timed illuminated entry with
theater-style fade-to-off and courtesy illumination
defeat features.
²Intermittent Wipe and Front Wiper System
Control- The BCM monitors inputs from the front
wiper and washer switch and the front wiper motor
park switch to provide front wiper system control
through the wiper on/off and high/low relays. This
includes support for adjustable intermittent wipe,
mist wipe (also known as pulse wipe), and wipe-after-
wash features.
²Key-In-Ignition Switch Status- The BCM
monitors and transmits the status of the key-in-igni-
tion switch.
²Panic Mode- The BCM provides support for
the Remote Keyless Entry (RKE) system panic mode
feature.
²Parade Mode- The BCM provides a parade
mode (also known as funeral mode) that allows the
interior Vacuum Fluorescent Displays (VFD) to be
illuminated at full intensity while driving in daylight
with the exterior lamps On.²Power Locks- The BCM monitors inputs from
the power lock switches and the Remote Keyless
Entry (RKE) module (optional) to provide control of
the power lock motors through outputs to the lock,
unlock, and driver unlock (RKE only) relays. This
includes support for rolling door locks (also known as
automatic door locks) and a door lock inhibit mode.
²Programmable Features- The BCM provides
support for several standard and optional program-
mable features, including: rolling door locks, head-
lamp time delay interval, Remote Keyless Entry
(RKE) driver-door-only or unlock-all-doors, RKE opti-
cal chirp, and RKE audible chirp.
²Remote Keyless Entry- The premium BCM
provides the optional Remote Keyless Entry (RKE)
system features, including support for the RKE Lock,
Unlock (with optional driver-door-only unlock, and
unlock-all-doors), rear flip-up glass control, Panic,
audible chirp, optical chirp, and illuminated entry
modes, as well as the ability to be programmed to
recognize up to four RKE transmitters.
²Rolling Door Locks- The BCM provides sup-
port for the power lock system rolling door locks fea-
ture (also known as automatic door locks).
²Tailgate and Flip-Up Glass Ajar Status- The
BCM monitors and transmits the status of the tail-
gate and rear flip-up glass ajar switches.
²Remote Radio Switch Interface- The pre-
mium BCM monitors and transmits the status of the
optional remote radio switches.
²Self-Diagnostics- The BCM provides support
for diagnostics through communication with the
DRBIIItscan tool over the PCI data bus network.
Each analog and digital input can be verified, and
each output can be actuated through the use of this
diagnostic protocol. The BCM also stores Diagnostic
Trouble Codes (DTCs) to assist in troubleshooting
this unit.
²Vacuum Fluorescent Display Synchroniza-
tion- The BCM transmits panel lamp intensity data
which allows modules with Vacuum Fluorescent Dis-
plays (VFD) to coordinate their illumination inten-
sity.
²Vehicle Speed System- The BCM monitors a
vehicle speed input from the vehicle speed sensor
(without Antilock Brake System [ABS]) or from the
Controller Antilock Brake (CAB)(with ABS), calcu-
lates the vehicle speed based upon a programmed
axle ratio/tire size (electronic pinion factor), and
transmits the vehicle speed information to the Pow-
ertrain Control Module (PCM) on a hard wired out-
put circuit.
²Vehicle Theft Security System- The pre-
mium BCM monitors inputs from the door cylinder
lock switches, the tailgate cylinder lock switch, the
door ajar switches, the tailgate ajar switch, the
8E - 4 ELECTRONIC CONTROL MODULESKJ
BODY CONTROL MODULE (Continued)

Schedule Condition Expected Operation
OverheatOil temperature above 240É F or
engine coolant temperature above
244É F- Delayed 2-3 upshift
- Delayed 3-4 upshift
- 3rd gear FEMCC from 30-48 mph
- 3rd gear PEMCC above 35 mph
- Above 25 mph the torque
converter will not unlock unless the
throttle is closed or if a wide open
throttle 2nd PEMCC to 1 kickdown
is made
STANDARD PROCEDURE - TCM QUICK LEARN
The quick learn procedure requires the use of the
DRBtscan tool.
This program allows the electronic transmission
system to recalibrate itself. This will provide the
proper transmission operation. The quick learn pro-
cedure should be performed if any of the following
procedures are performed:
²Transmission Assembly Replacement
²Transmission Control Module Replacement
²Solenoid Pack Replacement
²Clutch Plate and/or Seal Replacement
²Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the follow-
ing conditions must be met:
²The brakes must be applied
²The engine speed must be above 500 rpm
²The throttle angle (TPS) must be less than 3
degrees
²The shift lever position must stay in PARK until
prompted to shift to overdrive
²The shift lever position must stay in overdrive
after the Shift to Overdrive prompt until the DRBt
indicates the procedure is complete
²The calculated oil temperature must be above
60É and below 200É
HEATED SEAT MODULE
DESCRIPTION
The heated seat module is also known as the Seat
Heat Interface Module. The heated seat module (Fig.
14) is located under the left front seat cushion, where
it is secured to a mounting bracket via two push-pin
retainers. The heated seat module has a single con-
nector receptacle that allows the module to be con-
nected to all of the required inputs and outputs
through the seat wire harness.
The heated seat module is an electronic micropro-
cessor controlled device designed and programmed to
use inputs from the heated seat relay, the two heatedseat switches and the two heated seat sensors to
operate and control the heated seat elements in both
front seats and the two heated seat indicator lamp
Light-Emitting Diodes (LEDs) in each heated seat
switch. The heated seat module is also programmed
to perform self-diagnosis of certain heated seat sys-
tem functions and provide feedback of that diagnosis
through the heated seat switch indicator lamps.
The heated seat module cannot be repaired. If the
heated seat module is damaged or faulty, the entire
module must be replaced.
OPERATION
The heated seat module operates on fused battery
current received from a fuse in the junction block.
The module is grounded at all times. Inputs to the
module include a resistor multiplexed heated seat
switch request circuit for each of the two heated seat
switches and the heated seat sensor inputs from the
seat cushions of each front seat. In response to those
inputs, the heated seat module controls battery cur-
rent to the heated seat elements and sensors, and
Fig. 14 Heated Seat Module
1 - Mounting Tabs (Not Used On KJ)
2 - Heated Seat Module
3 - Connector Receptacle
KJELECTRONIC CONTROL MODULES 8E - 21
TRANSMISSION CONTROL MODULE (Continued)

perform its many functions. The EMIC module incor-
porates a blue-green digital Vacuum Fluorescent Dis-
play (VFD) for displaying odometer and trip
odometer information, as well as several warning
messages and certain diagnostic information. In addi-
tion to instrumentation and indicators, the EMIC has
the hardware and software needed to provide the fol-
lowing features:
²Chime Warning Service- A chime tone gener-
ator on the EMIC electronic circuit board provides
audible alerts to the vehicle operator and eliminates
the need for a separate chime module. (Refer to 8 -
ELECTRICAL/CHIME WARNING SYSTEM -
DESCRIPTION).
²Panel Lamps Dimming Service- The EMIC
provides a hard wired 12-volt Pulse-Width Modulated
(PWM) output that synchronizes the dimming level
of the radio display, gear selector indicator, heater-air
conditioner control, and all other dimmable lighting
on the panel lamps dimmer circuit with that of the
cluster illumination lamps and VFD.
The EMIC houses four analog gauges and has pro-
visions for up to twenty-four indicators (Fig. 2). The
EMIC includes the following analog gauges:
²Coolant Temperature Gauge
²Fuel Gauge
²Speedometer
²Tachometer
Some of the EMIC indicators are automatically
configured when the EMIC is connected to the vehi-
cle electrical system for compatibility with certain
optional equipment or equipment required for regula-
tory purposes in certain markets. While each EMIC
may have provisions for indicators to support every
available option, the configurable indicators will not
be functional in a vehicle that does not have the
equipment that an indicator supports. The EMIC
includes provisions for the following indicators (Fig.
2):
²Airbag Indicator (with Airbag System only)
²Antilock Brake System (ABS) Indicator
(with ABS only)
²Brake Indicator
²Charging Indicator
²Coolant Low Indicator (with Diesel Engine
only)
²Cruise Indicator (with Speed Control Sys-
tem only)
²Four-Wheel Drive Full Time Indicator (with
Selec-Trac Transfer Case only)
²Four-Wheel Drive Low Mode Indicator
²Four-Wheel Drive Part Time Indicator
²Front Fog Lamp Indicator (with Front Fog
Lamps only)
²High Beam Indicator
²Low Fuel Indicator²Low Oil Pressure Indicator
²Malfunction Indicator Lamp (MIL)
²Overdrive-Off Indicator (with Automatic
Transmission only)
²Rear Fog Lamp Indicator (with Rear Fog
Lamps only)
²Seatbelt Indicator
²Security Indicator (with Vehicle Theft
Security System only)
²Sentry Key Immobilizer System (SKIS)
Indicator (with SKIS only)
²Transmission Overtemp Indicator (with
Automatic Transmission only)
²Turn Signal (Right and Left) Indicators
²Wait-To-Start Indicator (with Diesel Engine
only)
²Water-In-Fuel Indicator (with Diesel Engine
only)
Each indicator in the EMIC is illuminated by a
dedicated Light Emitting Diode (LED) that is sol-
dered onto the EMIC electronic circuit board. The
LEDs are not available for service replacement and,
if damaged or faulty, the entire EMIC must be
replaced. Cluster illumination is accomplished by
dimmable incandescent back lighting, which illumi-
nates the gauges for visibility when the exterior
lighting is turned on. Each of the incandescent bulbs
is secured by an integral bulb holder to the electronic
circuit board from the back of the cluster housing.
The incandescent bulb/bulb holder units are available
for service replacement.
Hard wired circuitry connects the EMIC to the
electrical system of the vehicle. These hard wired cir-
cuits are integral to several wire harnesses, which
are routed throughout the vehicle and retained by
many different methods. These circuits may be con-
nected to each other, to the vehicle electrical system
and to the EMIC 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.
The EMIC modules for this model are serviced only
as complete units. The EMIC module cannot be
adjusted or repaired. If a gauge, an LED indicator,
the VFD, the electronic circuit board, the circuit
board hardware, the cluster overlay, or the EMIC
housing are damaged or faulty, the entire EMIC mod-
ule must be replaced. The cluster lens, hood and
mask unit and the individual incandescent lamp
bulbs with holders are available for service replace-
ment.
KJINSTRUMENT CLUSTER 8J - 3
INSTRUMENT CLUSTER (Continued)

OPERATION
The ElectroMechanical Instrument Cluster (EMIC)
is designed to allow the vehicle operator to monitor
the conditions of many of the vehicle components and
operating systems. The gauges and indicators in the
EMIC provide valuable information about the various
standard and optional powertrains, fuel and emis-
sions systems, cooling systems, lighting systems,
safety systems and many other convenience items.
The EMIC is installed in the instrument panel so
that all of these monitors can be easily viewed by the
vehicle operator when driving, while still allowing
relative ease of access for service. The microproces-sor-based EMIC hardware and software uses various
inputs to control the gauges and indicators visible on
the face of the cluster. Some of these inputs are hard
wired, but most are in the form of electronic mes-
sages that are transmitted by other electronic mod-
ules over the Programmable Communications
Interface (PCI) data bus network. (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/COMMUNICATION - OPERATION).
The EMIC microprocessor smooths the input data
using algorithms to provide gauge readings that are
accurate, stable and responsive to operating condi-
tions. These algorithms are designed to provide
Fig. 2 EMIC Gauges & Indicators
1 - SKIS INDICATOR 16 - REAR FOG LAMP INDICATOR
2 - AIRBAG INDICATOR 17 - ABS INDICATOR
3 - LOW FUEL INDICATOR 18 - CHARGING INDICATOR
4 - WAIT-TO-START INDICATOR 19 - WATER-IN-FUEL INDICATOR
5 - OVERDRIVE-OFF INDICATOR 20 - ENGINE TEMPERATURE GAUGE
6 - COOLANT LOW INDICATOR 21 - ODOMETER/TRIP ODOMETER SWITCH BUTTON
7 - SEATBELT INDICATOR 22 - ODOMETER/TRIP ODOMETER DISPLAY
8 - TACHOMETER 23 - CRUISE INDICATOR
9 - LEFT TURN INDICATOR 24 - LOW OIL PRESSURE INDICATOR
10 - HIGH BEAM INDICATOR 25 - TRANSMISSION OVERTEMP INDICATOR
11 - RIGHT TURN INDICATOR 26 - PART TIME 4WD INDICATOR
12 - SPEEDOMETER 27 - BRAKE INDICATOR
13 - FRONT FOG LAMP INDICATOR 28 - FULL TIME 4WD INDICATOR
14 - 4WD LOW MODE INDICATOR 29 - SECURITY INDICATOR
15 - MALFUNCTION INDICATOR LAMP (MIL) 30 - FUEL GAUGE
8J - 4 INSTRUMENT CLUSTERKJ
INSTRUMENT CLUSTER (Continued)

eter/trip odometer switch button that extends
through the lower edge of the cluster lens, just right
of the speedometer. Actuating this switch momen-
tarily with the ignition switch in the On position will
toggle the VFD between the odometer and trip odom-
eter modes. Depressing the switch button for about
two seconds while the VFD is in the trip odometer
mode will reset the trip odometer value to zero. Hold-
ing this switch depressed while turning the ignition
switch from the Off position to the On position will
initiate the EMIC self-diagnostic actuator test. The
VFD will also display the cluster software version
level near the completion of the EMIC self-diagnostic
actuator test. Refer to the appropriate diagnostic
information for additional details on this VFD func-
tion.
The VFD is diagnosed using the EMIC self-diag-
nostic actuator test. (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - DIAGNOSIS AND
TESTING). Proper testing of the PCI data bus and
the electronic data bus message inputs to the EMIC
that control some of the VFD functions requires the
use of a DRBIIItscan tool. Refer to the appropriate
diagnostic information. Specific operation details for
the odometer, the trip odometer, and the various
warning message functions of the VFD may be found
elsewhere in this service information.
INDICATORS Indicators are located in various
positions within the EMIC and are all connected to
the EMIC circuit board. The turn signal indicators,
security indicator, washer fluid indicator, and coolant
low indicator (diesel engine only) use hard wired
inputs to the EMIC. The brake indicator is controlled
by PCI data bus messages from the Controller
Antilock Brake (CAB) as well as by hard wired park
brake switch and brake fluid level switch inputs to
the EMIC. The Malfunction Indicator Lamp (MIL) is
normally controlled by PCI data bus messages from
the Powertrain Control Module (PCM); however, if
the EMIC loses PCI data bus communication, the
EMIC circuitry will automatically turn the MIL on
until PCI data bus communication is restored. The
EMIC uses PCI data bus messages from the Body
Control Module (BCM), the PCM, the Airbag Control
Module (ACM), and the CAB to control all of the
remaining indicators.
The various indicators are controlled by different
strategies; some receive fused ignition switch output
from the EMIC circuitry and have a switched ground,
others are grounded through the EMIC circuitry and
have a switched battery feed, while still others are
completely controlled by the EMIC microprocessor
based upon various hard wired and electronic mes-
sage inputs. Some indicators are illuminated at a
fixed intensity, while the illumination intensity ofothers is synchronized with that of the EMIC general
illumination lamps.
In addition, certain indicators in this instrument
cluster are automatically configured or self-config-
ured. This feature allows the configurable indicators
to be enabled by the EMIC circuitry for compatibility
with certain optional equipment. The ABS indicator,
airbag indicator, SKIS indicator are automatically
configured by PCI data bus messages received by the
EMIC from the CAB, ACM, or Sentry Key Immobi-
lizer Module (SKIM) after the EMIC is installed in
the vehicle. Once these configuration settings are
learned by the EMIC, the DRBIIItscan tool must be
used to remove these settings from the EMIC non-
volatile memory. The self-configured indicators
remain latent in each EMIC at all times and will be
activated only when the EMIC receives the appropri-
ate PCI message inputs for the optional system or
equipment.
The hard wired indicators are diagnosed using con-
ventional diagnostic methods. The EMIC and PCI
bus message controlled indicators are diagnosed
using the EMIC self-diagnostic actuator test. (Refer
to 8 - ELECTRICAL/INSTRUMENT CLUSTER -
DIAGNOSIS AND TESTING). Proper testing of the
PCI data bus and the electronic data bus message
inputs to the EMIC that control each indicator
require the use of a DRBIIItscan tool. Refer to the
appropriate diagnostic information. Specific details of
the operation for each indicator may be found else-
where in this service information.
CLUSTER ILLUMINATION The EMIC has several
illumination lamps that are illuminated when the
exterior lighting is turned on with the headlamp
(multi-function) switch. The illumination intensity of
these lamps is adjusted by a 12-volt Pulse Width
Modulated (PWM) output of the EMIC when the
interior lighting control ring on the left control stalk
of the multi-function switch is rotated (down to dim,
up to brighten) to one of six available minor detent
positions. The BCM provides electronic dimming
level messages based upon internal programming
and inputs it receives from the control knob and con-
trol ring on the left (lighting) control stalk of the
multi-function switch on the steering column, then
provides a control output to energize or de-energize
the park lamp relay as appropriate. The energized
park lamp relay provides battery current to the
EMIC on the hard wired fused park lamp relay out-
put circuit, and the BCM provides the electronic dim-
ming level message to the EMIC over the PCI data
bus. The EMIC electronic circuitry provides the
proper PWM output to the cluster illumination lamps
and the VFD on the EMIC circuit board, then pro-
vides a synchronized PWM output on the hard wired
8J - 6 INSTRUMENT CLUSTERKJ
INSTRUMENT CLUSTER (Continued)

(2) With the bulb holder fully seated against the
cluster electronic circuit board, turn the bulb holder
clockwise about sixty degrees to lock it into place.
(3) Reinstall the instrument cluster onto the
instrument panel. (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - INSTALLATION).
(4) Reconnect the battery negative cable.
CLUSTER LENS, HOOD, AND MASK
(1) Position the cluster lens, hood, and mask unit
over the face of the instrument cluster (Fig. 5). Be
certain that the odometer/trip odometer switch but-
ton is inserted through the proper clearance holes in
the mask and the lens.
(2) From the back of the instrument cluster, install
and tighten the six screws that secure the rear cover
and the lens, hood, and mask unit to the cluster
housing. Tighten the screws to 1 N´m (10 in. lbs.).
(3) Reinstall the instrument cluster onto the
instrument panel. (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - INSTALLATION).
(4) Reconnect the battery negative cable.
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 instrument cluster to the instru-
ment panel.
(2) Reconnect the instrument panel wire harness
connector for the cluster to the cluster connector
receptacle.
(3) Position the instrument cluster into the instru-
ment panel.
(4) Install and tighten the four screws that secure
the instrument cluster to the instrument panel (Fig.
3). Tighten the screws to 2 N´m (17 in. lbs.).
(5) Reinstall the cluster bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
CLUSTER BEZEL - INSTALLATION).
(6) Reconnect the battery negative cable.NOTE: Some of the indicators in this instrument
cluster are self configured or automatically config-
ured when the cluster is connected to the vehicle
electrical system. This feature allows those indica-
tors to be enabled for compatibility with certain
optional equipment. However, if an instrument clus-
ter was previously connected to another vehicle
with different equipment options than the current
vehicle, some of the automatically configured indi-
cator settings may have to be disabled using a
DRBIIITscan tool. Refer to the appropriate diagnos-
tic information.
ABS INDICATOR
DESCRIPTION
An Antilock Brake System (ABS) indicator is stan-
dard equipment on all instrument clusters. However,
the instrument cluster is programmed to automati-
cally enable this indicator only on vehicles equipped
with the optional antilock brake system. The ABS
indicator is located above the engine temperature
gauge and to the right of the speedometer in the
instrument cluster. The ABS indicator consists of a
stencil-like cutout of the International Control and
Display Symbol icon for ªFailure of Anti-lock Braking
Systemº in the opaque layer of the instrument clus-
ter overlay. The dark outer layer of the overlay pre-
vents the indicator from being clearly visible when it
is not illuminated. An amber Light Emitting Diode
(LED) behind the cutout in the opaque layer of the
overlay causes the icon to appear in amber through
the translucent outer layer of the overlay when it is
illuminated from behind by the LED, which is sol-
dered onto the instrument cluster electronic circuit
board. The ABS indicator is serviced as a unit with
the instrument cluster.
OPERATION
The ABS indicator gives an indication to the vehi-
cle operator when the ABS system is faulty or inop-
erative. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and electronic messages received by
the cluster from the Controller Antilock Brake (CAB)
over the Programmable Communications Interface
(PCI) data bus. The ABS indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster receives a battery current input on the fused
ignition switch output (run-start) circuit. Therefore,
the LED will always be off when the ignition switch
is in any position except On or Start. The LED only
KJINSTRUMENT CLUSTER 8J - 11
INSTRUMENT CLUSTER (Continued)

illuminates when it is provided a path to ground by
the instrument cluster transistor. The instrument
cluster will turn on the ABS indicator for the follow-
ing reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the ABS indicator is illu-
minated by the cluster for about three seconds as a
bulb test.
²ABS Lamp-On Message- Each time the clus-
ter receives a lamp-on message from the CAB, the
ABS indicator will be illuminated. The indicator
remains illuminated until the cluster receives a
lamp-off message from the CAB, or until the ignition
switch is turned to the Off position, whichever occurs
first.
²Communication Error- If the cluster receives
no lamp-on or lamp-off messages from the CAB for
six consecutive seconds, the ABS indicator is illumi-
nated. The indicator remains illuminated until the
cluster receives a valid message from the CAB, or
until the ignition switch is turned to the Off position,
whichever occurs first.
²Actuator Test- Each time the instrument clus-
ter is put through the actuator test, the ABS indica-
tor will be turned on, then off again during the bulb
check portion of the test to confirm the functionality
of the LED and the cluster control circuitry.
²ABS Diagnostic Test- The ABS indicator is
blinked on and off by lamp-on and lamp-off messages
from the CAB during the performance of the ABS
diagnostic tests.
The CAB continually monitors the ABS circuits
and sensors to decide whether the system is in good
operating condition. The CAB then sends the proper
lamp-on or lamp-off messages to the instrument clus-
ter. If the CAB sends a lamp-on message after the
bulb test, it indicates that the CAB has detected a
system malfunction and/or that the ABS system has
become inoperative. The CAB will each store a Diag-
nostic Trouble Code (DTC) for any malfunction it
detects. Each time the ABS indicator fails to light
due to an open or short in the cluster ABS indicator
circuit, the cluster sends a message notifying the
CAB of the condition, then the instrument cluster
and the CAB will each store a DTC. For proper diag-
nosis of the antilock brake system, the CAB, the PCI
data bus, or the message inputs to the instrument
cluster that control the ABS indicator, a DRBIIIt
scan tool is required. Refer to the appropriate diag-
nostic information.AIRBAG INDICATOR
DESCRIPTION
An airbag indicator is standard equipment on all
instrument clusters. However, the instrument cluster
is programmed to automatically enable this indicator
only on vehicles equipped with the airbag system,
which is not available in some markets. The airbag
indicator is located above the fuel gauge and to the
left of the tachometer in the instrument cluster. The
airbag indicator consists of a stencil-like cutout of the
words ªAIR BAGº in the opaque layer of the instru-
ment cluster overlay. The dark outer layer of the
overlay prevents the indicator from being clearly vis-
ible when it is not illuminated. A red Light Emitting
Diode (LED) behind the cutout in the opaque layer of
the overlay causes the ªAIR BAGº text to appear in
red through the translucent outer layer of the over-
lay when it is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The airbag indicator is serviced
as a unit with the instrument cluster.
OPERATION
The airbag indicator gives an indication to the
vehicle operator when the airbag system is faulty or
inoperative. The airbag indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and electronic mes-
sages received by the cluster from the Airbag Control
Module (ACM) over the Programmable Communica-
tions Interface (PCI) data bus. The airbag indicator
Light Emitting Diode (LED) is completely controlled
by the instrument cluster logic circuit, and that logic
will only allow this indicator to operate when the
instrument cluster receives a battery current input
on the fused ignition switch output (run-start) cir-
cuit. Therefore, the LED will always be off when the
ignition switch is in any position except On or Start.
The LED only illuminates when it is provided a path
to ground by the instrument cluster transistor. The
instrument cluster will turn on the airbag indicator
for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the airbag indicator is illu-
minated for about six seconds. The entire six second
bulb test is a function of the ACM.
²ACM Lamp-On Message- Each time the clus-
ter receives a lamp-on message from the ACM, the
airbag indicator will be illuminated. The indicator
remains illuminated for about twelve seconds or until
the cluster receives a lamp-off message from the
ACM, whichever is longer.
²Communication Error- If the cluster receives
no airbag messages for six consecutive seconds, the
airbag indicator is illuminated. The indicator
8J - 12 INSTRUMENT CLUSTERKJ
ABS INDICATOR (Continued)