overhead JEEP LIBERTY 2002 KJ / 1.G Workshop Manual

(4) Using hand pressure, pull the cargo lamp
switch toward the outside of the lamp unit housing
until it unsnaps from the housing.
(5) Continue sliding the cargo lamp switch away
from the terminal pins and out of the lamp unit
housing.
INSTALLATION
(1) Align the terminal receptacles in the cargo
lamp switch with the terminal pins of the lamp unit
housing (Fig. 6).
(2) Using hand pressure, push the cargo lamp
switch toward the terminals of the lamp unit housing
until it snaps into the housing.
(3) Reinstall the cargo lamp unit onto the head-
liner near the rear roof header. (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - INTERIOR/CARGO
LAMP UNIT - INSTALLATION).
(4) Reconnect the battery negative cable.
CARGO LAMP UNIT
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Using a trim stick or another suitable wide
flat-bladed tool, gently pry between the flange
around the edge of the cargo lamp unit housing and
the headliner to release the metal snap clip on each
side of the housing from the receptacles in the rear
roof header (Fig. 7).(3) Pull the cargo lamp unit away from the head-
liner far enough to access and disconnect the rear
body wire harness connector for the lamp from the
connector receptacle on the lamp unit housing.
(4) Remove the cargo lamp unit from the mounting
hole in the headliner.
INSTALLATION
(1) Position the cargo lamp unit to the mounting
hole in the headliner.
(2) Reconnect the rear body wire harness connec-
tor for the cargo lamp to the connector receptacle on
the lamp unit housing.
(3) With the finger depression in the cargo lamp
lens oriented towards the rear of the vehicle, position
the cargo lamp unit housing into the headliner
mounting hole and align the metal snap clip on each
side of the housing with their receptacles in the rear
roof header (Fig. 7).
(4) Using hand pressure, press upward firmly and
evenly on both ends of the cargo lamp unit until both
snap clips are fully engaged in their receptacles.
(5) Reconnect the battery negative cable.
COMPASS MINI-TRIP
ILLUMINATION BULB
REMOVAL
The Compass Mini-Trip Computer (CMTC) in the
overhead console includes either two or three incan-
descent illumination bulb and bulb holder units.
Three bulbs are used only on models that also fea-
ture the optional Universal Garage Door Opener
(UGDO).
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.
Fig. 7 Cargo Lamp Unit Remove/Install
1 - CARGO LAMP UNIT
2 - HEADLINER
3 - TRIM STICK
8L - 74 LAMPS/LIGHTING - INTERIORKJ
CARGO LAMP SWITCH (Continued)

(1) Disconnect and isolate the battery negative
cable.
(2) Remove the overhead console from the head-
liner. (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - REMOVAL).
(3) From the back of the unit, use a small thin-
bladed screwdriver to rotate the compass mini-trip
illumination bulb holder counterclockwise about 30
degrees on the circuit board (Fig. 8).
(4) Pull the compass mini-trip illumination bulb
holder and bulb unit straight out of the circuit board
bulb mounting hole.
INSTALLATION
The Compass Mini-Trip Computer (CMTC) in the
overhead console includes either two or three incan-
descent illumination bulb and bulb holder units.
Three bulbs are used only on models that also fea-
ture the optional Universal Garage Door Opener
(UGDO).
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 SUPPLEMENTALRESTRAINT 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 compass mini-trip illumination bulb
holder and bulb unit with the circuit board bulb
mounting hole.
(2) Insert the compass mini-trip illumination bulb
holder and bulb unit straight into the circuit board
bulb mounting hole until it is firmly seated (Fig. 8).
(3) Using a small thin-bladed screwdriver, rotate
the compass mini-trip illumination bulb holder clock-
wise about 30 degrees on the circuit board.
(4) Reinstall the overhead console onto the head-
liner. (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - INSTALLATION).
(5) Reconnect the battery negative cable.
COURTESY LAMP 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) Support the courtesy lamp unit housing with
one hand while firmly grasping the flange on the
outer circumference of the lens with the other hand,
then pull the lens straight down to unsnap it from
the housing (Fig. 9).
(3) Pull the courtesy lamp bulb straight out of the
lamp unit socket.
Fig. 8 Compass Mini-Trip Illumination Bulb
Remove/Install
1 - OVERHEAD CONSOLE
2 - BULB & HOLDER (3)
3 - COMPASS MINI-TRIP COMPUTER
KJLAMPS/LIGHTING - INTERIOR 8L - 75
COMPASS MINI-TRIP ILLUMINATION BULB (Continued)

READING LAMP 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) If the vehicle is not equipped with the optional
Compass Mini-Trip Computer (CMTC), remove the
reading lamp unit from the headliner mounting hole.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
INTERIOR/READING LAMP UNIT - REMOVAL). If
the vehicle is equipped with the optional CMTC,
remove the overhead console from the headliner.
(Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE -
REMOVAL).
(3) From the back of the unit while pulling the
reading lamp socket away from the outside of the
lamp unit bulb housing, use a small thin-bladed
screwdriver to release the integral latch tabs of the
socket from the inside of the bulb housing (Fig. 12).
(4) Pull the reading lamp socket and bulb unit
straight out from the lamp unit bulb housing.
(5) Pull the ash reading lamp bulb straight out of
the lamp unit socket.
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 base of the reading lamp bulb with
the receptacle in the lamp unit socket.
(2) Push the reading lamp bulb straight into the
lamp unit socket until it is firmly seated.
(3) Align the reading lamp socket and bulb unit
with the mounting hole in the bulb housing (Fig. 12).
(4) Push the reading lamp socket and bulb unit
straight into the bulb housing until it is firmly
seated and the integral socket latches are engaged
within the bulb housing.
(5) If the vehicle is not equipped with the optional
Compass Mini-Trip Computer (CMTC), reinstall the
reading lamp unit into the headliner mounting hole.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
INTERIOR/READING LAMP - INSTALLATION). If
the vehicle is equipped with the optional CMTC,
reinstall the overhead console onto the headliner.
(Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE -
INSTALLATION).
(6) Reconnect the battery negative cable.
Fig. 12 Reading Lamp Bulb Remove/Install
1 - BEZEL
2 - BULB HOUSING
3 - SWITCH (2)
4 - BULB (2)
5 - SOCKET (2)
KJLAMPS/LIGHTING - INTERIOR 8L - 79

READING LAMP UNIT
REMOVAL
If the vehicle is equipped with an optional Com-
pass Mini-Trip Computer (CMTC), the reading lamps
are housed in the overhead console. (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE - REMOV-
AL).
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) Using a trim stick or another suitable wide
flat-bladed tool, gently pry between the flange
around the edge of the reading lamp unit housing
and the headliner to release the metal snap clip on
each side of the housing from the receptacles in the
mounting bracket above the headliner (Fig. 14).
(3) Pull the reading lamp unit away from the
headliner far enough to access and disconnect the
body wire harness connector for the lamp from the
connector on the lamp unit housing.
(4) If the vehicle is equipped with an optional
power sunroof, disconnect the body wire harness con-
nector for the sunroof switch from the connector
receptacle on the back of the switch.
(5) Remove the reading lamp unit from the mount-
ing hole in the headliner.
INSTALLATION
If the vehicle is equipped with an optional Com-
pass Mini-Trip Computer (CMTC), the reading lamps
are housed in the overhead console. (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE - INSTALLA-
TION).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERINGWHEEL, 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 reading lamp unit to the mounting
hole in the headliner.
(2) If the vehicle is equipped with an optional
power sunroof, reconnect the body wire harness con-
nector for the sunroof switch to the connector recep-
tacle on the back of the switch.
(3) Reconnect the body wire harness connector for
the reading lamp to the connector on the lamp unit
housing.
(4) With the curved corners of the reading lamp
lenses oriented towards the rear of the vehicle, posi-
tion the reading lamp unit housing into the headliner
mounting hole and align the metal snap clip on each
side of the housing with their receptacles in the
mounting bracket above the headliner (Fig. 14).
(5) Using hand pressure, press upward firmly and
evenly on both ends of the reading lamp unit until
both snap clips are fully engaged in their receptacles.
(6) Reconnect the battery negative cable.
Fig. 14 Reading Lamp Unit Remove/Install
1 - TRIM STICK
2 - SUNROOF SWITCH
3 - READING LAMP UNIT
4 - HEADLINER
5 - LENS (2)
KJLAMPS/LIGHTING - INTERIOR 8L - 81

MESSAGE SYSTEMS
TABLE OF CONTENTS
page page
OVERHEAD CONSOLE
DESCRIPTION..........................1
OPERATION............................2
STANDARD PROCEDURE
STANDARD PROCEDURE - CMTC LAMP
REPLACEMENT.......................2
STANDARD PROCEDURE - COURTESY
LAMP REPLACEMENT..................2
STANDARD PROCEDURE - COMPASS
CALIBRATION.........................2
STANDARD PROCEDURE - COMPASS
DEMAGNETIZING......................2
STANDARD PROCEDURE - COMPASS
VARIATION ADJUSTMENT................3
REMOVAL
OVERHEAD CONSOLE - REMOVAL........4
INSTALLATION..........................4
COMPASS/MINI-TRIP COMPUTER
DESCRIPTION..........................4
OPERATION............................5
DIAGNOSIS AND TESTING - COMPASS
MINI-TRIP COMPUTER..................6REMOVAL.............................7
INSTALLATION..........................8
UNIVERSAL TRANSMITTER
DESCRIPTION..........................8
OPERATION............................8
DIAGNOSIS AND TESTING - UNIVERSAL
TRANSMITTER........................8
STANDARD PROCEDURE
STANDARD PROCEDURE - ERASING
TRANSMITTER CODES..................8
STANDARD PROCEDURE - SETTING
TRANSMITTER CODES..................9
AMBIENT TEMP SENSOR
DESCRIPTION..........................9
OPERATION............................9
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AMBIENT
TEMPERATURE SENSOR................9
DIAGNOSIS AND TESTING - AMBIENT
TEMPERATURE SENSOR CIRCUIT.........9
REMOVAL.............................10
INSTALLATION.........................10
OVERHEAD CONSOLE
DESCRIPTION
An overhead console is standard factory-installed
equipment on this model. The available overheadconsoles can include the Compass Mini-Trip Com-
puter with universal transmitter (Fig. 2), without the
universal transmitter (Fig. 1), or base console with
only two reading and courtesy lamps (Fig. 3). All
overhead consoles are equipped with two reading and
courtesy lamps. On vehicles equipped with a power
Fig. 1 Overhead Console Without Universal
Transmitter
Fig. 2 Overhead Console With Universal Transmitter
KJMESSAGE SYSTEMS 8M - 1

sunroof, the sunroof switch is located between the
two reading and courtesy lamps. The overhead con-
sole is mounted with one screw and two snap clips to
a molded plastic retainer bracket located above the
headliner.
OPERATION
Refer to the vehicle Owner's Manual for specific
operation of each overhead console and its systems.
STANDARD PROCEDURE
STANDARD PROCEDURE - CMTC LAMP
REPLACEMENT
(1) Open hood, disconnect and isolate the negative
battery cable.
(2) Remove overhead console (Refer to 8 - ELEC-
TRICAL/OVERHEAD CONSOLE - REMOVAL).
(3) Using a flat blade screwdriver twist out the
lamp socket.
(4) Replace lamp(s) as necessary.
STANDARD PROCEDURE - COURTESY LAMP
REPLACEMENT
(1) Open hood, disconnect and isolate the negative
battery cable.
(2) Remove the overhead console from the head-
liner (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - REMOVAL).
(3) Remove the lamp and socket assembly from the
overhead console.
(4) Remove the lamp bulb by pulling it straight
out of its socket.
STANDARD PROCEDURE - COMPASS
CALIBRATION
CAUTION: Do not place any external magnets, such
as magnetic roof mount antennas, in the vicinity of
the compass. Do not use magnetic tools when ser-
vicing the overhead console.The electronic compass unit features a self-cali-
brating design, which simplifies the calibration pro-
cedure. This feature automatically updates the
compass calibration while the vehicle is being driven.
This allows the compass unit to compensate for small
changes in the residual magnetism that the vehicle
may acquire during normal use. If the compass read-
ings appear to be erratic or out of calibration, per-
form the following calibration procedure. Also, new
service replacement Compass Mini-Trip Computer
(CMTC) modules must have their compass calibrated
using this procedure. Do not attempt to calibrate the
compass near large metal objects such as other vehi-
cles, large buildings, or bridges; or, near overhead or
underground power lines.
NOTE: Whenever the compass is calibrated manu-
ally, the variance number must also be reset. Refer
to Compass Variation Adjustment in this group.
Calibrate the compass manually as follows:
(1) Turn the ignition switch to the On position. If
the compass/thermometer data is not currently being
displayed, momentarily depress and release the C/T
push button to reach the compass/thermometer dis-
play.
(2) Depress the Reset push button and hold the
button down until ªCALº appears in the display. This
takes about ten seconds, and appears about five sec-
onds after ªVARIANCE = XXº is displayed.
(3) Release the Reset push button.
(4) Drive the vehicle on a level surface, away from
large metal objects and power lines, through three or
more complete circles at between five and eight kilo-
meters-per-hour (three and five miles-per-hour) in
not less than 48 seconds. The ªCALº message will
disappear from the display to indicate that the com-
pass is now calibrated.
NOTE: If the ªCALº message remains in the display,
either there is excessive magnetism near the com-
pass, or the unit is faulty. Repeat the calibration
procedure one more time.
NOTE: If the wrong direction is still indicated in the
compass display, the area selected for calibration
may be too close to a strong magnetic field. Repeat
the calibration procedure in another location.STANDARD PROCEDURE - COMPASS
DEMAGNETIZING
A degaussing tool (Special Tool 6029) is used to
demagnetize, or degauss, the overhead console for-
ward mounting screw and the roof panel above the
overhead console. Equivalent units must be rated as
Fig. 3 Base Console
8M - 2 MESSAGE SYSTEMSKJ
OVERHEAD CONSOLE (Continued)

continuous duty for 110/115 volts and 60 Hz. They
must also have a field strength of over 350 gauss at 7
millimeters (0.25 inch) beyond the tip of the probe.
To demagnetize the roof panel and the overhead
console forward mounting screw, proceed as follows:
(1) Be certain that the ignition switch is in the Off
position, before you begin the demagnetizing proce-
dure.
(2) Connect the degaussing tool to an electrical
outlet, while keeping the tool at least 61 centimeters
(2 feet) away from the compass unit.
(3) Slowly approach the head of the overhead con-
sole forward mounting screw with the degaussing
tool connected.
(4) Contact the head of the screw with the plastic
coated tip of the degaussing tool for about two sec-
onds.
(5) With the degaussing tool still energized, slowly
back it away from the screw. When the tip of the tool
is at least 61 centimeters (2 feet) from the screw
head, disconnect the tool.
(6) Place a piece of paper approximately 22 by 28
centimeters (8.5 by 11 inches), oriented on the vehicle
lengthwise from front to rear, on the center line of
the roof at the windshield header (Fig. 4). The pur-
pose of the paper is to protect the roof panel from
scratches, and to define the area to be demagnetized.
(7) Connect the degaussing tool to an electrical
outlet, while keeping the tool at least 61 centimeters
(2 feet) away from the compass unit.
(8) Slowly approach the center line of the roof
panel at the windshield header, with the degaussing
tool connected.
(9) Contact the roof panel with the plastic coated
tip of the degaussing tool. Be sure that the template
is in place to avoid scratching the roof panel. Using a
slow, back-and-forth sweeping motion, and allowing
13 millimeters (0.50 inch) between passes, move the
tool at least 11 centimeters (4 inches) to each side of
the roof center line, and 28 centimeters (11 inches)
back from the windshield header.
(10) With the degaussing tool still energized,
slowly back it away from the roof panel. When the
tip of the tool is at least 61 centimeters (2 feet) from
the roof panel, disconnect the tool.
(11) Calibrate the compass and adjust the compass
variance (Refer to 8 - ELECTRICAL/OVERHEAD
CONSOLE - STANDARD PROCEDURE).
STANDARD PROCEDURE - COMPASS
VARIATION ADJUSTMENT
Compass variance, also known as magnetic decli-
nation, is the difference in angle between magnetic
north and true geographic north. In some geographic
locations, the difference between magnetic and geo-
graphic north is great enough to cause the compassto give false readings. If this problem occurs, the
compass variance setting may need to be changed.
To set the compass variance:
(1) Using the Variance Settings map, find your
geographic location and note the zone number (Fig.
5).
(2) Turn the ignition switch to the On position. If
the compass/thermometer data is not currently being
displayed, momentarily depress and release the C/T
push button to reach the compass/thermometer dis-
play.
(3) Depress the Reset push button and hold the
button down until ªVARIANCE = XXº appears in the
display. This takes about five seconds.
(4) Release the Reset push button. ªVARIANCE
=XX º will remain in the display. ªXXº equals the cur-
rent variance zone setting.
(5) Momentarily depress and release the Step push
button to step through the zone numbers, until the
zone number for your geographic location appears in
the display.
(6) Momentarily depress and release the Reset
push button to enter the displayed zone number into
the CMTC module memory.
(7) Confirm that the correct directions are now
indicated by the compass.
Fig. 4 Roof Demagnetizing Pattern
KJMESSAGE SYSTEMS 8M - 3
OVERHEAD CONSOLE (Continued)

REMOVAL
OVERHEAD CONSOLE - REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the overhead console retaining screw,
located in the front of console near the windshield.
(3) Using your fingertips, grasp the sides of the
overhead console and pull straight down evenly to
disengage the two snap clips at the rear of the unit.
(4) Lower the overhead console far enough to
access the wire harness connectors.
(5) Disconnect the control module, courtesy lamps
and power sunroof switch electrical connectors, if
equipped.
(6) Remove the overhead console assembly from
the vehicle.
INSTALLATION
(1) Position the overhead console in the vehicle
and connect the wire harness connectors.
(2) Connect the control module, courtesy lamps
and power sunroof switch electrical connectors, if
equipped.
(3) Grasp the sides of the overhead console and
push straight up evenly to engage the two snap clips
at the rear of the unit.
(4) Install the overhead console retaining screw,
located in the front of console near the windshield.
Torque the screw to 1.2 N´m (10 in. lbs.).
(5) Connect the negative battery cable.
COMPASS/MINI-TRIP
COMPUTER
DESCRIPTION
The Compass Mini-Trip Computer (CMTC) is
located in the overhead console on models equipped
with this option. The Compass Mini-Trip Computer
module features a large Vacuum Fluorescent Display
(VFD) screen for displaying information, and four
back-lit push button function switches labeled C/T
(compass/thermometer), RESET, STEP, and US/M
(United States/Metric Scale).
The Compass Mini-Trip Computer module contains
a central processing unit and interfaces with other
electronic modules in the vehicle over the Program-
mable Communications Interface (PCI) data bus net-
work. The PCI data bus network allows the sharing
of sensor information. This helps to reduce wire har-
ness complexity, reduce internal controller hardware,
and reduce component sensor current loads. At the
same time, this system provides increased reliability,
enhanced diagnostics, and allows the addition of
many new feature capabilities.
The Compass Mini-Trip Computer module contains
six informational displays which can be displayed
using the four outer buttons on the overhead console.
When the vehicle is first turned ON:
²CMTC blanks the display for a half second
²Displays whatever was being viewed when the
ignition was last turned OFF
Fig. 5 Variance Settings
8M - 4 MESSAGE SYSTEMSKJ
OVERHEAD CONSOLE (Continued)

The CMTC may also be integrated with the Uni-
versal Transmitter. If so, your CMTC module will
have three buttons centered together between the
outer four buttons. Below the three buttons are cor-
responding dots to indicate which button you are
using.
The Compass Mini-Trip Computer includes the fol-
lowing display options:
²Compass and thermometer- provides the out-
side temperature and one of eight compass readings
to indicate the direction the vehicle is facing.
²Average fuel economy- shows the average
fuel economy since the last trip computer reset.
²Distance to empty- shows the estimated dis-
tance that can be travelled with the fuel remaining
in the fuel tank. This estimated distance is computed
using the average miles-per-gallon from the last 30
gallons of fuel used.
²Instant fuel economy- shows the present fuel
economy based upon the current vehicle distance and
fuel used information.
²Trip odometer- shows the distance travelled
since the last trip computer reset.
²Elapsed time- shows the accumulated igni-
tion-on time since the last trip computer reset.
²Blank screen- the CMTC compass/thermome-
ter/trip computer VFD is turned off.
If the vehicle is equipped with the optional Univer-
sal Transmitter transceiver, the CMTC will also dis-
play messages and an icon indicating when the
Universal Transmitter is being trained, which of the
three transmitter buttons is transmitting, and when
the transceiver is cleared.
Data input for all CMTC functions, including VFD
dimming level, is received through PCI data bus
messages. The CMTC module uses its internal pro-
gramming and all of its data inputs to calculate and
display the requested data. If the data displayed is
incorrect, perform the self-diagnostic tests as
described in this group. If these tests prove inconclu-
sive, the use of a DRBIIItscan tool and the proper
Diagnostic Procedures manual are recommended for
further testing of the CMTC module and the PCI
data bus.
The CMTC module cannot be repaired, and is
available for service only as a unit. This unit
includes the push button switches and the plastic
module and display lens. If any of these components
is faulty or damaged, the complete CMTC module
must be replaced. The incandescent bulbs used for
CMTC push button back-lighting are available for
service replacement.
DESCRIPTION - COMPASS
While in the compass/thermometer mode, the com-
pass will display the direction in which the vehicle ispointed using the eight major compass headings
(Examples: north is N, northeast is NE). The self-cal-
ibrating compass unit requires no adjusting in nor-
mal use. The only calibration that may prove
necessary is to drive the vehicle in three complete
circles at 5 to 8 kilometers-per-hour (3 to 5 miles-per-
hour), on level ground, in not less than forty-eight
seconds. This will reorient the compass unit to its
vehicle.
The compass unit also will compensate for magne-
tism the body of the vehicle may acquire during nor-
mal use. However, avoid placing anything magnetic
directly on the roof of the vehicle. Magnetic mounts
for an antenna, a repair order hat, or a funeral pro-
cession flag can exceed the compensating ability of
the compass unit if placed on the roof panel. Mag-
netic bit drivers used on the fasteners that hold the
overhead console assembly to the roof header can
also affect compass operation. If the vehicle roof
should become magnetized, the demagnetizing and
calibration procedures found in this group may be
required to restore proper compass operation.
DESCRIPTION - THERMOMETER
The thermometer displays the outside ambient
temperature in whole degrees. The temperature dis-
play can be toggled from Fahrenheit to Celsius by
using the U.S./Metric button. The displayed temper-
ature is not an instant reading of conditions, but an
average temperature. It may take the thermometer
display several minutes to respond to a major tem-
perature change, such as driving out of a heated
garage into winter temperatures.
When the ignition switch is turned to the Off posi-
tion, the last displayed temperature reading stays in
the Body Control Module (BCM) unit memory. When
the ignition switch is turned to the On position
again, the CMTC will display the memory tempera-
ture for one minute; then update the display to the
current average temperature reading within five
minutes.
The thermometer function is supported by an
ambient temperature sensor. The sensor is mounted
outside the passenger compartment near the front
and center of the vehicle, and is hard wired to the
Body Control Module (BCM). The BCM sends tem-
perature status messages to the CMTC module over
the PCI data bus network. The ambient temperature
sensor is available as a separate service item, refer to
additional information later in this section.
OPERATION
The compass mini-trip computer operates when the
ignition is in the ON position. The VFD will display
the last display before ignition was turned OFF. The
four outer buttons operate:
KJMESSAGE SYSTEMS 8M - 5
COMPASS/MINI-TRIP COMPUTER (Continued)

²STEP
²C/T - Compass/Temperature
²US/M - English/Metric
²RESET
1. STEP BUTTON
Pressing the STEP button selects one of the follow-
ing 6 displays:
²Average fuel economy
²Distance to empty
²Instantaneous fuel economy
²Trip odometer
²Elapsed time
²Blank Screen
2. C/T (COMPASS/TEMPERATURE)
BUTTON
Pressing the C/T button selects the Compass/Tem-
perature display.
3. US/M (ENGLISH/METRIC
MEASUREMENT) BUTTON
Pressing the US/M button switches the display
units between English and Metric readings.
4. RESET BUTTON
Pressing the RESET button resets the function on
the display, provided that function can be reset. The
functions which can be reset are Average fuel econ-
omy, Trip odometer and Elapsed time.
Global ResetThis feature allows all three dis-
plays (Average fuel economy, Trip odometer and
Elapsed time) to be reset easily, by pressing the
RESET button twice within three seconds with any
of the screens in display. This eliminates the need to
reset each display individually.
The RESET button is also used to set the variance
and/or calibrate the compass. Refer to the Variance
Procedure and Calibration Procedure in this section.
For more information on the features, control func-
tions and setting procedures for the CMTC module,
see the owner's manual in the vehicle glove box.
DIAGNOSIS AND TESTING - COMPASS
MINI-TRIP COMPUTER
The following diagnostic procedure can be used if
the compass mini-trip computer is not operational in
any way. If the problem is specific to a individual
CMTC display, go to the appropriate display title
noted below and diagnose using the information pro-
vided on how these displays are generated.
(1) Remove the overhead console from the head-
liner (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - REMOVAL).
(2) Using a ohmmeter, check the ground circuit
cavity of the compass mini-trip computer electricalconnector for proper continuity to ground. Continuity
should be present, If OK go to Step 3, If not OK
repair the open or shorted ground circuit as required.
NOTE: Connect the negative battery cable before
proceeding.
(3) Using a voltmeter, check the fused (B+) circuit
cavity of the compass mini-trip computer electrical
connector for 12v. Voltage should be present, If OK go
to Step 4, If not OK repair the open or shorted fused
(B+) circuit as required.
(4) Using a voltmeter, check the fused ignition
switch output circuit cavity of the compass mini-trip
computer electrical connector for 12v with Key ON.
Voltage should be present, If OK, replace the inoper-
ative CMTC module, If not OK repair the open or
shorted fused ignition switch output circuit as
required.
TEMPERATURE
The compass mini-trip computer receives Program-
mable Communications Interface bus (PCI bus) mes-
sages from the Body Control Module (BCM) for all
displayed information except the compass display. If
a dash (-) is displayed, the compass mini-trip com-
puter is not receiving a PCI bus message from the
BCM. To check out the PCI bus line and the BCM,
use the DRB llltscan tool and proper Body Diagnos-
tic Procedure Manual.
If the compass mini-trip computer displays a tem-
perature more than 54É C (130É F), check for a short
circuit between the temperature sensor and the
BCM.
If the compass mini-trip computer displays a tem-
perature less than -40É C (-67É F), check for an open
circuit between the temperature sensor and the
BCM.
AVERAGE FUEL ECONOMY
The compass mini-trip computer receives average
fuel economy information from the BCM over the PCI
bus line. If the compass mini-trip computer displays
-.- instead of an average fuel economy value, it is not
receiving a PCI bus message for the average fuel
economy from the BCM. To check out the PCI bus
line and the BCM use the DRB llltscan tool and
proper Body Diagnostic Procedure Manual.
DISTANCE TO EMPTY
The compass mini-trip computer receives distance
to empty information from the BCM over the PCI bus
line. If compass mini-trip computer displays a dash
(-) instead of a distance to empty value, it is not
receiving a PCI bus message for the distance to
empty from the BCM. To check out the PCI bus line
8M - 6 MESSAGE SYSTEMSKJ
COMPASS/MINI-TRIP COMPUTER (Continued)