roof JEEP GRAND CHEROKEE 2002 WJ / 2.G Workshop Manual

INSTALLATION
(1) Position the antenna base and lead into the
rear of the right front fender wheel house opening.
(2) Insert the antenna base into the mounting hole
in the top of the right front fender.
(3) Install the antenna escutcheon onto the
antenna base on the top of the right front fender.
(4) Install and tighten the antenna base cap nut
using an antenna nut wrench (Special Tool C-4816).
Tighten the cap nut to 6.8 N´m (60 in. lbs.).
(5) Install the plastic shroud onto the antenna
base cap nut.
(6) Install and tighten the antenna mast onto the
antenna base. Tighten the antenna mast to 3.3 N´m
(30 in. lbs.).
(7) Reach through the rear of the right front
fender wheel house opening to access and insert the
antenna lead coaxial cable and connector into the
passenger compartment through the hole in the right
cowl side outer panel.
(8) From the right front fender wheel house, seat
the antenna lead grommet into the hole in the right
cowl side outer panel.
(9) Install the lower rear half of the inner liner
into the right front fender wheel house.
(10) Reach under the passenger side of the instru-
ment panel near the right cowl side inner panel to
reconnect the antenna coaxial cable connector halves.
(11) Install the trim panel onto the right inner
cowl side.
(12) Install the scuff plate onto the right front door
sill.
(13) Reconnect the battery negative cable.
ANTENNA MODULE - EXPORT
DESCRIPTION
The antenna module (Fig. 7) is an electromagnetic
circuit component designed to capture and enhance
RF (Radio Frequency) signals in both the AM and
FM broadcast bands. The antenna module is
mounted to the right rear roof rail under the head-
liner. The modules mounting brackets also double as
the ground circuit. The module has a two wire elec-
trical connector that connects to the electric backlite
integral radio antenna, located on the right rear
quarter glass, a connector for the radio coax cable
and a connector for battery voltage.
Fig. 5 Antenna Mast Remove/Install - Typical
1 - ANTENNA MAST
2 - ADAPTER
3 - CAP NUT
Fig. 6 Antenna Base Cap Nut Remove/Install -
Typical
1 - CAP NUT
2 - ANTENNA ADAPTER
3 - TOOL
8A - 10 AUDIOWJ
ANTENNA BODY & CABLE (Continued)

REMOVAL
(1) Remove the headliner. (Refer to 23 - BODY/IN-
TERIOR/HEADLINER - REMOVAL)
(2) Disconnect the battery power lead connector
from the antenna module.
(3) Disconnect the antenna module connector from
the integral antenna (Fig. 8).
(4) Remove the mounting screws and the antenna
module.
(5) Disconnect the coax lead from the antenna
module.
INSTALLATION
(1) Plug coax into antenna module.
(2) Position antenna module onto right side upper
roof rail and install screws. Tighten the screws to 8
N´m (71 in. lbs.).
(3) Connect antenna module lead to the integral
antenna.
(4) Connect battery power supply lead to antenna
module.
(5) Install headliner. (Refer to 23 - BODY/INTERI-
OR/HEADLINER - INSTALLATION)
CD CHANGER
DESCRIPTION
A factory-installed Compact Disc (CD) changer fea-
turing a ten-CD magazine is an available option on
this model when it is also equipped with the pre-
mium speaker package and a radio receiver including
the CD controls feature. The CD changer is mounted
in the cargo area of the passenger compartment on
the right rear quarter panel.
The CD changer is connected to a take out from
the right body wire harness and receives both ground
and radio-switched battery current through the radio
receiver. The controls on the radio receiver operate
the CD changer through messages sent over the Pro-
grammable Communications Interface (PCI) data bus
network. The two-channel audio outputs of the CD
changer are hard wired back to the radio receiver,
which then outputs the signal through four channels
to the power amplifier. For diagnosis of the messag-
ing functions of the radio receiver and the CD
changer, or of the PCI data bus, a DRB scan tool and
the proper Diagnostic Procedures manual are
required.
Fig. 8 ANTENNA MODULE
1 - COAX
2 - RIGHT SIDE ROOF RAIL
3 - ANTENNA MODULE4 - ANTENNA MODULE TO ANTENNA CONNECTOR
5 - SCREW (2)
8A - 12 AUDIOWJ
ANTENNA MODULE - EXPORT (Continued)

COURTESY LAMP
REMOVAL
REMOVAL - BULB
(1) Remove the door trim panel. (Refer to 23 -
BODY/DOOR - FRONT/TRIM PANEL - REMOVAL)
for the service procedures.
(2) Remove the bulb socket from the lamp.
(3) Remove the bulb from the socket.
REMOVAL - LAMP
(1) Remove door trim panel. (Refer to 23 - BODY/
DOOR - FRONT/TRIM PANEL - REMOVAL) for the
procedures.
(2) Disengage the electrical connectors.
(3) Depress the locking tabs and remove the lamp
module.
(4) Remove the bulb socket.
INSTALLATION
INSTALLATION - BULB
(1) Install the bulb in the socket.
(2) Install the bulb socket in the lamp.
(3) Install the door trim panel.
INSTALLATION - LAMP
(1) Install the bulb socket into the lamp module.
(2) Align the lamp module with the door trim
panel.
(3) Snap the lamp module into place.
(4) Install the door panel.
DOME LAMP
REMOVAL
REMOVAL - BULB
(1) Rotate the the grab handle down.
(2) Remove the screws retaining the grab handle/
dome lens.
(3) Remove the grab handle/lens from the module.
(4) Remove the bulb from the lamp terminals.
REMOVAL - LAMP
It will be necessary to partially remove the head-
liner to remove the bulb socket.
(1) Remove the screws holding the grab handle/
lens assembly to the headliner and roof panel.(2) Lower the headliner as needed. (Refer to 23 -
BODY/INTERIOR/HEADLINER - REMOVAL) for the
service procedure.
(3) Separate the lamp socket from the headliner
and roof panel.
(4) Disconnect the wire connector.
INSTALLATION
INSTALLATION - BULB
(1) Insert the bulb into the lamp terminals.
(2) Position the grab handle/lens on the lamp mod-
ule.
(3) Install the screws retaining the grab handle/
lens to the lamp module.
INSTALLATION - LAMP
(1) Position the lamp socket on the headliner and
roof panel.
(2) Connect the wire harness.
(3) Install the headliner.
(4) Position the grab handle/lens on the lamp mod-
ule.
(5) Install the screws retaining the grab handle/
lens into the lamp socket.
DOOR AJAR SWITCH
DESCRIPTION
DESCRIPTION - DOOR AJAR SWITCH
The door ajar switches are integral to the door
latch mechnicism. The front door ajar switches are
actuated by the front door latch mechanisms, and are
hard wired between a body ground and the Driver
Door Module (DDM) or the Passenger Door Module
(PDM). The rear door ajar switches are actuated by
the rear door latch mechanisms, and are hard wired
between a body ground and the Body Control Module
(BCM) through the rear door and body wire har-
nesses.
The door ajar switches cannot be adjusted or
repaired and, if faulty or damaged, the door latch
unit must be replaced. (Refer to 23 - BODY/DOOR -
FRONT/LATCH - REMOVAL) or (Refer to 23 -
BODY/DOORS - REAR/LATCH - REMOVAL) for the
service procedures. For complete circuit diagrams,
refer to the appropriate wiring information.
DESCRIPTION - FLIP UP GLASS AJAR SWITCH
The liftgate flip-up glass ajar switch is integral to
the liftgate flip-up glass latch mechnicism. The lift-
gate flip-up glass ajar switch is actuated by the lift-
gate flip-up glass latch mechanism, and is hard
WJLAMPS/LIGHTING - INTERIOR 8L - 29

READING LAMP
DESCRIPTION
The overhead console in this vehicle is equipped
with two individual reading and courtesy lamps.Each
lamp has its own switch, bulb, reflector and lens; but
both lamps share a common lamp housing within the
overhead console.
The overhead console reading and courtesy lamps
operate on battery current that is provided at all
times, regardless of the ignition switch position. The
ground feed for the lamps is switched through the
integral reading and courtesy lamp switches or
through the door jamb switches.
The reading and courtesy lamp lenses and the
lamp housing and reflector unit are serviced only as
a unit with the overhead console housing.The reading
and courtesy lamp switches, bulb holders and wiring
are only available as part of the overhead console
wire harness.
For service of the reading and courtesy lamp bulbs,
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
INTERIOR/READING LAMP - REMOVAL). For diag-
nosis of the reading and courtesy lamps, refer to the
appropriate wiring information.
OPERATION
All reading and courtesy lamps located in the over-
head console are activated by the door jamb switches.
When all of the doors are closed, these lamps can be
individually activated by depressing the correspond-
ing lens. When any door is open, depressing the lamp
lenses to activate the lamp switches will not turn the
lamps off.
REMOVAL
(1) Remove the overhead console.
(2) Rotate the console until the bulb is visible (Fig.
2).
(3) Grasp the bulb and remove from the socket.
INSTALLATION
(1) Push the bulb into the bulb socket.
(2) Install the console on the headliner and roof
panel.
(3) Align the screw hole and install the screw.
TRANS RANGE INDICATOR
ILLUMINATION
DESCRIPTION
The Transmission Range Indicator Lamp, mounted
on the floor console, uses electroluminescent technol-ogy as the light source. This lamp requires a 120 volt
AC signal that is provided by a power converter
included as part of the assembly. The module is not
serviceable separately. Because of a potential shock
hazard, diagnostic testing of the lamp assembly
should be avoided. Refer to TRANSMISSION, Range
Selector Assembly Removal and Installation.
VANITY LAMP
REMOVAL
(1) Fold down the visor.
(2) Using a small flat blade, and staring at the
base of the lamp assembly, carefully pry the base of
the lamp from the visor.
(3) Disconnect the vanity lamp visor and remove
the lamp from the vehicle.
INSTALLATION
(1) Position the lamp at the visor and connect the
wire connector.
(2) Press the lamp in place.
Fig. 2 Overhead Console Reading Lamp Bulb
1 - BULB
8L - 32 LAMPS/LIGHTING - INTERIORWJ

MESSAGE SYSTEMS
TABLE OF CONTENTS
page page
OVERHEAD CONSOLE
DESCRIPTION..........................1
OPERATION............................1
STANDARD PROCEDURE
STANDARD PROCEDURE - MODULE LAMP
REPLACEMENT.......................1
STANDARD PROCEDURE - COURTESY
LAMP REPLACEMENT..................1
STANDARD PROCEDURE - MODULE LENS
REPLACEMENT.......................2
STANDARD PROCEDURE - ELECTRONIC
VEHICLE INFORMATION CENTER
PROGRAMMING.......................2
STANDARD PROCEDURE - COMPASS
DEMAGNETIZING......................4
STANDARD PROCEDURE - COMPASS
CALIBRATION.........................5
STANDARD PROCEDURE - COMPASS
VARIATION ADJUSTMENT................5
REMOVAL.............................5
INSTALLATION..........................6
SPECIAL TOOLS
OVERHEAD CONSOLE SYSTEMS.........6
ELECTRONIC VEHICLE INFO CENTER
DESCRIPTION..........................6OPERATION............................9
DIAGNOSIS AND TESTING - ELECTRONIC
VEHICLE INFORMATION CENTER.........9
STANDARD PROCEDURE - TIRE PRESSURE
SYSTEM TEST.......................10
REMOVAL.............................10
INSTALLATION.........................10
UNIVERSAL TRANSMITTER
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - UNIVERSAL
TRANSMITTER.......................11
AMBIENT TEMP SENSOR
DESCRIPTION.........................12
OPERATION...........................12
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AMBIENT
TEMPERATURE SENSOR...............12
DIAGNOSIS AND TESTING - AMBIENT
TEMPERATURE SENSOR CIRCUIT........12
REMOVAL.............................12
INSTALLATION.........................13
OVERHEAD CONSOLE
DESCRIPTION
An overhead console is standard factory-installed
equipment on this model. The overhead console
includes the Electronic Vehicle Information Center
(EVIC) and two reading and courtesy lamps (Fig. 1).
On vehicles equipped with a power sunroof option,
the overhead console also houses the power sunroof
switch between the two reading and courtesy lamps.
The overhead console is mounted with one screw and
two snap-clips to a molded plastic retainer bracket
located above the headliner. The retainer bracket is
secured with adhesive to the inside surface of the
roof panel.
Following are general descriptions of the major
components used in the overhead console. Refer to
Overhead Consolein Wiring Diagrams for complete
circuit diagrams.
OPERATION
See the owner's manual in the vehicle glove box for
more information on the use and operation of the
various overhead console features.
STANDARD PROCEDURE
STANDARD PROCEDURE - MODULE LAMP
REPLACEMENT
(1) Remove the overhead console (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE - REMOV-
AL).
(2) Using a flat blade screwdriver twist out socket/
lamp (Fig. 2).
(3) Replace lamp(s) as necessary.
STANDARD PROCEDURE - COURTESY LAMP
REPLACEMENT
(1) Open hood, disconnect and isolate the negative
battery cable.
WJMESSAGE SYSTEMS 8M - 1

(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 - MODULE LENS
REPLACEMENT
(1) Remove the overhead console (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE - REMOV-
AL).
(2) Remove the electronics module from the over-
head console. Refer to the procedure in this section.
(3) Unsnap the lens from the module and replace
lens as necessary.
STANDARD PROCEDURE - ELECTRONIC
VEHICLE INFORMATION CENTER
PROGRAMMING
EVIC PROGRAMMING MODE
The Electronic Vehicle Information Center (EVIC)
provides the vehicle operator with a user interface,
which allows the selection of several optional cus-
tomer programmable electronic features to suit indi-
vidual preferences. The EVIC must be placed into its
programming mode in order to view or change the
programmable features. To enter the EVIC program-
ming mode and to view or change the selected pro-
grammable features options, proceed as follows:
(1) Turn the ignition switch to the On position.
(2) Depress and release the Menu push button.
The first item in the programmable features menu
list will appear in the EVIC display.
(3) Momentarily depress and release the Menu
push button to step through the programmable fea-
tures list. Each programmable feature and its cur-
rently selected option will appear on the EVIC
display in the sequence shown in the Programmable
Features list that follows.
(4) Momentarily depress and release the Step push
button to step through the available options for the
programmable feature being displayed.
(5) The option that last appears in the display
with a programmable feature before exiting the pro-
gramming mode, becomes the newly selected pro-
grammable feature option.
(6) The EVIC exits the programming mode and
returns to its normal operating mode when the C/T
push button is depressed or when the end of the pro-
grammable features menu list is reached, whichever
occurs first.
Fig. 1 Overhead Console
1 - POWER SUNROOF SWITCH (IF EQUIPPED)
2 - READING AND COURTESY LAMPS
3 - UNIVERSAL GARAGE DOOR OPENER PUSH BUTTONS (IF
EQUIPPED)
4 - SCREW
5 - ELECTRONIC VEHICLE INFORMATION CENTER PUSH
BUTTONS
Fig. 2 Top of Overhead Console
1 - OVERHEAD CONSOLE HOUSING
2 - EVIC MODULE
3 - ILLUMINATION LAMPS
4 - SCREWS (4)
8M - 2 MESSAGE SYSTEMSWJ
OVERHEAD CONSOLE (Continued)

²RETRAIN TIRE SENSORS?- This program-
mable feature only applies to vehicles equipped with
the optional tire pressure monitoring system. The
options include Yes and No. The default is No. When
Yes is selected and the menu button is depressed, the
EVIC will enter the training mode starting with the
left front tire.
²EASY EXIT SEAT?- This programmable fea-
ture only applies to vehicles equipped with the
optional memory system. The options include Yes and
No. The default is No. When Yes is selected, the
driver seat moves rearward about 55 millimeters
(two inches) or to the farthest rearward position,
whichever comes first, when the key is removed from
the ignition switch lock cylinder. This provides addi-
tional ease for exiting from the vehicle. The seat will
automatically return to the memory system setting
position when the Driver 1 or Driver 2 button of the
memory switch on the door panel is depressed or, if
theREMOTE LINKED TO MEMORYprogramma-
ble feature is enabled, when the RKE Unlock button
is depressed. While not automatic, an easy entry fea-
ture can be obtained by enabling theEASY EXIT
SEATfeature and disabling theREMOTE LINKED
TO MEMORYfeature. Then theEASY EXIT SEAT
feature will move the seat back, but the RKE unlock
event will not reposition the seat. Thus, the seat
remains positioned for easy entry, and the memory
switch on the door panel can be depressed after
entering the vehicle to return the seat to the desired
memory position.
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
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. 3). 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
Fig. 3 Roof Demagnetizing Pattern
8M - 4 MESSAGE SYSTEMSWJ
OVERHEAD CONSOLE (Continued)

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
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 Electronic Vehicle Information
Center (EVIC) modules must have their compass cal-
ibrated using this procedure. Do not attempt to cali-
brate the compass near large metal objects such as
other vehicles, large buildings, or bridges; or, near
overhead or underground power lines.
NOTE: Whenever an EVIC module is replaced, the
variance number must also be reset. Refer to Com-
pass Variation Adjustment in this group.
Calibrate the compass manually as follows:
(1) Turn the ignition switch to the On position. If
the compass/temperature data is not currently being
displayed, momentarily depress and release the C/T
push button to reach the compass/temperature 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 one
complete circle at between five and eight kilometers-
per-hour (three and five miles-per-hour) in not less
than 20 seconds. The ªCALº message will disappear
from the display to indicate that the compass 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
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 compass
to 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.
4).
(2) Turn the ignition switch to the On position. If
the compass/temperature data is not currently being
displayed, momentarily depress and release the C/T
push button to reach the compass/temperature 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 EVIC module memory.
(7) Confirm that the correct directions are now
indicated by the compass.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the screw that secures the front of the
overhead console to the front of the overhead console
retainer bracket.
(3) Insert the fingertips of both hands between the
headliner and the sides of the overhead console hous-
ing in the area near the reading and courtesy lamps.
(4) Pull downward on the sides of the overhead
console housing firmly and evenly to disengage the
two snap clips that secure the rear of the unit from
their receptacles in the overhead console retainer
bracket.
(5) Lower the overhead console from the headliner
far enough to access the wire harness connectors.
WJMESSAGE SYSTEMS 8M - 5
OVERHEAD CONSOLE (Continued)

(6) Disconnect the roof wire harness connectors
from the Electronic Vehicle Information Center con-
nector receptacle, the reading and courtesy lamp wire
harness connector and, if the vehicle is so equipped,
from the back of the power sunroof switch.
(7) Remove the overhead console from the head-
liner.
INSTALLATION
(1) Position the overhead console near the mount-
ing location on the headliner.
(2) Reconnect the roof wire harness connectors to
the Electronic Vehicle Information Center connector
receptacle, the reading and courtesy lamp wire har-
ness connector and, if the vehicle is so equipped, to
the back of the power sunroof switch.
(3) Align the two snap clips on the rear of the
overhead console housing with their receptacles in
the overhead console retainer bracket.
(4) Push upward firmly and evenly on the sides of
the overhead console housing over both of the snap
clip locations until each of the two snap clips is fully
engaged with its receptacle in the overhead console
retainer bracket.
(5) Install and tighten the screw that secures the
front of the overhead console housing to the overhead
console retainer bracket. Tighten the screw to 1.2
N´m (10 in. lbs.).
(6) Reconnect the battery negative cable.
SPECIAL TOOLS
OVERHEAD CONSOLE SYSTEMS
ELECTRONIC VEHICLE INFO
CENTER
DESCRIPTION
The Electronic Vehicle Information Center (EVIC)
is located in the overhead console on models
equipped with this option. Three versions of the
EVIC module are available on the Grand Cherokee.
These three versions are identical except that some
models include an integral three-push button Univer-
sal Transmitter transceiver and/or Tire Pressure
Monitoring System (TPM). All three EVIC modules
feature a large Vacuum Fluorescent Display (VFD)
screen for displaying information, and back-lit push
buttons function switches labeled C/T (compass/tem-
perature), RESET, STEP, and MENU. The VFD
screen can also display a vehicle graphic that is used
Fig. 4 Variance Settings
Degaussing Tool 6029
8M - 6 MESSAGE SYSTEMSWJ
OVERHEAD CONSOLE (Continued)

messages. The EVIC 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 EVIC module and the PCI data
bus.
The EVIC module cannot be repaired, and is avail-
able for service only as a unit. This unit includes the
push button switches and the plastic housed module.
If any of these components are faulty or damaged,
the complete EVIC module must be replaced. The
incandescent bulbs used for EVIC push button back-
lighting and the display lens are available for service
replacement.
ELECTRONIC VEHICLE INFORMATION CENTER
CHIME
The Electronic Vehicle Information Center (EVIC)
uses the chime warning system for two different
kinds of support. In addition to requesting chime
tones from the Body Control Module (BCM) as tactile
beep support, the EVIC is programmed to send chime
request messages over the Programmable Communi-
cations Interface (PCI) data bus when it detects the
following conditions:
²Door Open Warning- A door is open above a
critical speed [about 16 kilometers-per-hour (10
miles-per-hour) for the driver side front door, or
about 5 kilometers-per-hour (3 miles-per-hour) for
any other door].
²Liftgate Open Warning- The liftgate is open
above a critical speed [about 5 kilometers-per-hour (3
miles-per-hour)].
²Liftglass Open Warning- The liftgate flip-up
glass is open above a critical speed [about 5 kilome-
ters-per-hour (3 miles-per-hour)].
²Low Coolant Level Warning- The coolant
level in the engine coolant reservoir is low.
²Perform Service Alert- An audible alert that
a ªPerform Serviceº reminder message is being dis-
played by the EVIC.
²Turn Signal On Warning- A turn signal
remains on for about 1.6 kilometers (one mile).
²Washer Fluid Low Warning- The fluid level
in the washer reservoir is low.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the EVIC. (Refer to 8 - ELECTRICAL/OVERHEAD
CONSOLE/ELECTRONIC VEHICLE INFO CENTER
- DESCRIPTION) for more information on the EVIC.
COMPASS
While in the compass/temperature mode, the com-
pass will display the direction in which the vehicle is
pointed 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 one circle at 5 to
8 kilometers-per-hour (3 to 5 miles-per-hour), on level
ground, in not less than 20 seconds. This will reori-
ent 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.
TEMPERATURE
The outside ambient temperature is displayed in
whole degrees. The temperature display can be tog-
gled from Fahrenheit to Celsius by selecting the
desired U.S./Metric option from the customer pro-
grammable features as described inELECTRONIC
VEHICLE INFORMATION CENTER PROGRAM-
MINGin the Standard Procedures section of this
group. The displayed temperature is not an instant
reading of conditions, but an average temperature. It
may take the temperature display several minutes to
respond to a major temperature change, such as driv-
ing 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 EVIC will display the memory tempera-
ture for one minute; then update the display to the
current average temperature reading within five
minutes.
The temperature function is supported by an ambi-
ent temperature sensor. The sensor is mounted out-
side the passenger compartment near the front and
center of the vehicle, and is hard wired to the Body
Control Module (BCM). The BCM sends temperature
status messages to the EVIC module over the PCI
data bus network. The ambient temperature sensor
is available as a separate service item.
8M - 8 MESSAGE SYSTEMSWJ
ELECTRONIC VEHICLE INFO CENTER (Continued)