section 5 DODGE RAM 1500 1998 2.G Owner's Guide
Page 480 of 2627
(5) Install the appropriate seat cushion or seat
back trim cover. Make certain the seat wire harness
is correctly routed through the seat and seat back.
HEATED SEAT SENSOR
DESCRIPTION
The heated seat temperature sensor is a Negative
Temperature Coefficient (NTC) thermistor. One tem-
perature sensor is used for each seat. This tempera-
ture sensor is located in the seat cushion heating
element on all models.
The heated seat temperature sensor cannot be
repaired or adjusted and must be replaced if defec-
tive. The heated seat cushion element must be
replaced if the temperature sensor is defective. Refer
to the procedure in this section of the service man-
ual.
OPERATION
When the temperature of the seat cushion cover
rises, the resistance of the sensor decreases. The
heated seat module supplies five-volts to one side of
each sensor, and monitors the voltage drop through
the sensor on a return circuit. The heated seat mod-
ule uses this temperature sensor input to monitor
the temperature of the seat, and regulates the cur-
rent flow to the seat heating elements accordingly.
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR
NOTE: Any resistance values (OHMSV) given in the
following text are supplied using the automatic
range generated by a FLUKETautomotive meter. If
another type of measuring device is used, the val-
ues generated may not be the same as the results
shown here, or may have to be converted to the
range used here.
(1) Position the driver seat in the full rearward
position.
(2) Unclip the heated seat module from the bottom
of the drivers seat cushion pan.
(3) Back-probe the heated seat module wire har-
ness connector, do not disconnect. Check cavity (#7
for passenger, #8 for driver seat) for a range in volt-
age from approx. 1.72 ± 3.0 volts. It should be within
this range, If OK check the heated seat element. If
NOT OK, check for the proper 5 volt supply to the
heated seat sensor, from the module. Refer to Wiring
for specific information. If 5 volts is not being sup-
plied to the sensor from the module, replace the
heated seat module.
(4) Test the seat wire harness between the heated
seat module connector and the heated seat wire har-
ness connector for shorted or open circuits. If OK,
refer toDiagnosis and Testing the Heated Seat
Modulein Electronic Control Modules, for the
proper heated seat module diagnosis and testing pro-
cedures. If not OK, repair the shorted or open heated
seat wire harness as required.
REMOVAL
(1) For heated seat sensor replacement procedure
(Refer to 8 - ELECTRICAL/HEATED SEATS/
HEATED SEAT ELEMENT - REMOVAL).
HEATED SEAT SWITCH
DESCRIPTION
The momentary, bidirectional rocker-type heated
seat switch (Fig. 4) provides a resistor-multiplexed
signal to the heated seat module via a mux circuit.
Each switch has a center neutral position and
momentary Low and High positions so that both the
driver and the front seat passenger can select a pre-
ferred level of seat heating. Each heated seat switch
has two Light-Emitting Diode (LED) indicator lamps,
which indicate the selected mode (Low or High) of
the seat heater. These indicator lamps also provide
diagnostic feedback for the heated seat system. Each
switch also has an incandescent bulb, which provides
Fig. 3 Heating Element Installation
1 - ORIGINAL (INOPERATIVE) HEATING ELEMENT
2 - REPLACEMENT HEATING ELEMENT
DRHEATED SEAT SYSTEM 8G - 11
HEATED SEAT ELEMENT (Continued)
Page 483 of 2627
The heated seat module is an electronic micropro-
cessor controlled device designed and programmed to
use inputs from the battery, the two heated seat
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 per-
form self-diagnosis of certain heated seat system
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 the integrated power module.
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 con-
trols battery current feeds to the heated seat ele-
ments and sensors, and controls the ground for the
heated seat switch indicator lamps.
When a heated seat switch (Driver or Passenger) is
depressed a signal is received by the heated seat
module, the module energizes the proper indicator
LED (Low or High) in the switch by grounding the
indicator lamp circuit to indicate that the heated seat
system is operating. At the same time, the heated
seat module energizes the selected heated seat sensor
circuit and the sensor provides the module with an
input indicating the surface temperature of the
selected seat cushion.The Low heat set point is about 36É C (96.8É F),
and the High heat set point is about 42É C (107.6É F).
If the seat cushion surface temperature input is
below the temperature set point for the selected tem-
perature setting, the heated seat module energizes
an N-channel Field Effect Transistor (N-FET) within
the module which energizes the heated seat elements
in the selected seat cushion and back. When the sen-
sor input to the module indicates the correct temper-
ature set point has been achieved, the module
de-energizes the N-FET which de-energizes the
heated seat elements. The heated seat module will
continue to cycle the N-FET as needed to maintain
the selected temperature set point.
If the heated seat module detects a heated seat
sensor value input that is out of range or a shorted
or open heated seat element circuit, it will notify the
vehicle operator or the repair technician of this con-
dition by flashing the High and/or Low indicator
lamps in the affected heated seat switch. Refer to
Diagnosis and Testing Heated Seat Systemin
Heated Systems for flashing LED diagnosis and test-
ing procedures. Refer toDiagnosis and Testing
Heated Seat Modulein this section for heated seat
module diagnosis and testing procedures.
DIAGNOSIS AND TESTING - HEATED SEAT
MODULE
If a heated seat fails to heat and one or both of the
indicator lamps on a heated seat switch flash, refer
toDiagnosis and Testing Heated Seat Systemin
Heated Seats for the location of flashing LED heated
seat system diagnosis and testing procedures. If a
heated seat heats but one or both indicator lamps on
the heated seat switch fail to operate, test the heated
seat switch. Refer toDiagnosis and Testing
Heated Seat Switchin Heated Seats for heated
seat switch diagnosis and testing procedures. If the
heated seat switch checks OK, proceed as follows.
(1) Check the heated seat element (Refer to 8 -
ELECTRICAL/HEATED SEATS/HEATED SEAT
ELEMENT - DIAGNOSIS AND TESTING).
(2) Check the heated seat sensor (Refer to 8 -
ELECTRICAL/HEATED SEATS/HEATED SEAT
SENSOR - DIAGNOSIS AND TESTING).
(3) Check the heated seat switch (Refer to 8 -
ELECTRICAL/HEATED SEATS/DRIVER HEATED
SEAT SWITCH - DIAGNOSIS AND TESTING).
NOTE: Refer to Wiring for the location of complete
heated seat system wiring diagrams and connector
pin-out information.
(4) Using a voltmeter, backprobe the appropriate
heated seat module connector, do not disconnect.
Check for voltage at the appropriate pin cavities. 12v
Fig. 5 Heated Seat Module
1 - MOUNTING TABS (NOT USED ON DR)
2 - HEATED SEAT MODULE
3 - ELECTRICAL CONNECTOR RECEPTACLE
8G - 14 HEATED SEAT SYSTEMDR
HEATED SEAT MODULE (Continued)
Page 504 of 2627
SPARK PLUG
DESCRIPTION
Resistor type spark plugs are used on all engines.
Sixteen spark plugs (2 per cylinder) are used with
5.7L V-8 engines.
DIAGNOSIS AND TESTING - SPARK PLUG
CONDITIONS
To prevent possible pre-ignition and/or mechanical
engine damage, the correct type/heat range/number
spark plug must be used.
Always use the recommended torque when tighten-
ing spark plugs. Incorrect torque can distort the
spark plug and change plug gap. It can also pull the
plug threads and do possible damage to both the
spark plug and the cylinder head.
Remove the spark plugs and examine them for
burned electrodes and fouled, cracked or broken por-
celain insulators. Keep plugs arranged in the order
in which they were removed from the engine. A sin-
gle plug displaying an abnormal condition indicates
that a problem exists in the corresponding cylinder.
Replace spark plugs at the intervals recommended in
the Lubrication and Maintenance section.
Spark plugs that have low mileage may be cleaned
and reused if not otherwise defective, carbon or oil
fouled.
CAUTION: Never use a motorized wire wheel brush
to clean the spark plugs. Metallic deposits will
remain on the spark plug insulator and will cause
plug misfire.
Spark plug resistance values range from 6,000 to
20,000 ohms (when checked with at least a 1000 volt
spark plug tester).Do not use an ohmmeter to
check the resistance values of the spark plugs.
Inaccurate readings will result.
NORMAL OPERATING
The few deposits present on the spark plug will
probably be light tan or slightly gray in color. This is
evident with most grades of commercial gasoline
(Fig. 23). There will not be evidence of electrode
burning. Gap growth will not average more than
approximately 0.025 mm (.001 in) per 3200 km (2000
miles) of operation. Spark plugs that have normal
wear can usually be cleaned, have the electrodes
filed, have the gap set and then be installed.Some fuel refiners in several areas of the United
States have introduced a manganese additive (MMT)
for unleaded fuel. During combustion, fuel with MMT
causes the entire tip of the spark plug to be coated
with a rust colored deposit. This rust color can be
misdiagnosed as being caused by coolant in the com-
bustion chamber. Spark plug performance may be
affected by MMT deposits.
COLD FOULING/CARBON FOULING
Cold fouling is sometimes referred to as carbon
fouling. The deposits that cause cold fouling are basi-
cally carbon (Fig. 23). A dry, black deposit on one or
two plugs in a set may be caused by sticking valves
or defective spark plug cables. Cold (carbon) fouling
of the entire set of spark plugs may be caused by a
clogged air cleaner element or repeated short operat-
ing times (short trips).
WET FOULING OR GAS FOULING
A spark plug coated with excessive wet fuel or oil
is wet fouled. In older engines, worn piston rings,
leaking valve guide seals or excessive cylinder wear
can cause wet fouling. In new or recently overhauled
engines, wet fouling may occur before break-in (nor-
mal oil control) is achieved. This condition can usu-
ally be resolved by cleaning and reinstalling the
fouled plugs.
OIL OR ASH ENCRUSTED
If one or more spark plugs are oil or oil ash
encrusted (Fig. 24), evaluate engine condition for the
cause of oil entry into that particular combustion
chamber.
Fig. 23 NORMAL OPERATION AND COLD (CARBON)
FOULING
1 - NORMAL
2 - DRY BLACK DEPOSITS
3 - COLD (CARBON) FOULING
DRIGNITION CONTROL 8I - 17
Page 508 of 2627
(4) Install ignition coil(s). Refer to Ignition Coil
Removal/Installation.
5.7L V-8
(1) Special care should be taken when installing
spark plugs into the cylinder head spark plug wells.
Be sure the plugs do not drop into the plug wells as
electrodes can be damaged.
(2) Start the spark plug into cylinder head by
hand to avoid cross threading aluminum threads. To
aid in installation, attach a piece of rubber hose, or
an old spark plug boot to spark plug.
(3) The 5.7L V-8 is equipped with torque critical
design spark plugs. Do not exceed 15 ft. lbs. torque.
Tighten spark plugs. Refer to torque specifications.
(4) Before installing spark plug cables to either the
spark plugs or coils, apply dielectric grease to inside
of boots.
(5) To prevent ignition crossfire, spark plug cables
MUSTbe placed in cable tray (routing loom) into
their original position. Refer to Spark Plug Cable
Removal for a graphic.
(6) Install ignition coil(s) to necessary spark plugs.
Refer to Ignition Coil Installation.
(7) Install spark plug cables to remaining spark
plugs. Remember to apply dielectric grease to inside
of boots.
IGNITION COIL CAPACITOR
DESCRIPTION
One coil capacitor is used. It is located in the right-
rear section of the engine compartment.
OPERATION
The coil capacitor(s) help dampen the amount of
conducted electrical noise to the camshaft position
sensor, crankshaft position sensor, and throttle posi-
tion sensor. This noise is generated on the 12V sup-
ply wire to the ignition coils and fuel injectors.
REMOVAL
The coil capacitor is located in the right-rear sec-
tion of the engine compartment. It is attached with a
mounting stud and nut.
(1) Disconnect electrical connector at capacitor
(Fig. 31).
(2) Remove mounting nut and remove ground
strap.
(3) Remove capacitor.
INSTALLATION
(1) Position capacitor to mounting stud.
(2) Position ground strap to mounting stud.
(3) Tighten nut to 7 N´m (60 in. lbs.) torque.
(4) Connect electrical connector to coil capacitor.
SPARK PLUG CABLE
DESCRIPTION
Spark plug cables are sometimes referred to as sec-
ondary ignition wires, or secondary ignition cables.
Plug cables are used only on the 5.7L V-8 engine.
OPERATION
The spark plug cables transfer electrical current
from the ignition coil(s) and/or distributor, to individ-
ual spark plugs at each cylinder. The resistive spark
plug cables are of nonmetallic construction. The
cables provide suppression of radio frequency emis-
sions from the ignition system.
Plug cables are used only on the 5.7L V-8 engine.
Fig. 31 CAPACITOR LOCATION
1 - COIL CAPACITOR
2 - MOUNTING STUD
3 - GROUND STRAP
4 - MOUNTING NUT
5 - ELEC. CONNECT.
DRIGNITION CONTROL 8I - 21
SPARK PLUG (Continued)
Page 571 of 2627
(3) Install the bolts attaching headlamp unit to the
fender (Fig. 11).
(4) Align the seal and install the push pins.
(5) Connect the battery negative cable.
ADJUSTMENTS
Headlamps can be aligned using the screen method
provided in this section.
LAMP ALIGNMENT SCREEN PREPARATION
(1) Position vehicle on a level surface perpendicu-
lar to a flat wall 7.62 meters (25 ft) away from front
of headlamp lens (Fig. 12).
(2) If necessary, tape a line on the floor 7.62
meters (25 ft) away from and parallel to the wall.
(3) Up 1.27 meters (5 feet) from the floor, tape a
line on the wall at the centerline of the vehicle. Sight
along the centerline of the vehicle (from rear of vehi-
cle forward) to verify accuracy of the line placement.
(4) Rock vehicle side-to-side three times to allow
suspension to stabilize.
(5) Jounce front suspension three times by pushing
downward on front bumper and releasing.
(6) Measure the distance from the center of head-
lamp lens to the floor. Transfer measurement to thealignment screen (with tape). Use this line for
up/down adjustment reference.
(7) Measure distance from the centerline of the
vehicle to the center of each headlamp being aligned.
Transfer measurements to screen (with tape) to each
side of vehicle centerline. Use these lines for left/
right adjustment reference.
VEHICLE PREPARATION FOR HEADLAMP
ALIGNMENT
(1) Verify headlamp dimmer switch and high beam
indicator operation.
(2) Correct defective components that could hinder
proper headlamp alignment.
(3) Verify proper tire inflation.
(4) Clean headlamp lenses.
(5) Verify that luggage area is not heavily loaded.
(6) Fuel tank should be FULL. Add 2.94 kg (6.5
lbs.) of weight over the fuel tank for each estimated
gallon of missing fuel.
HEADLAMP ALIGNMENT
A properly aimed low beam headlamp will project
top edge of high intensity pattern on screen from 50
mm (2 in.) above to 50 mm (2 in.) below headlamp
Fig. 12 Headlamp Alignment Screen - Typical
1 - CENTER OF VEHICLE
2 - CENTER OF HEADLAMP3 - 7.62 METERS (25 FT.)
4 - FRONT OF HEADLAMP
8L - 16 LAMPS/LIGHTING - EXTERIORDR
HEADLAMP UNIT (Continued)
Page 582 of 2627
(4) Push the right side of the lamp in the head-
liner opening and push the lamp lens up into the
lamp to secure (Fig. 1).
DOOR AJAR SWITCH
DESCRIPTION
The door ajar switches are integral to the door
latches on each door. The switches close a path to
ground for the Instrument Cluster when a door is
opened.
The door ajar switches cannot be repaired and, if
faulty or damaged, the door latch unit must be
replaced. Refer to the Body section under Doors for
the removal and installation procedure.
OPERATION
The door ajar switches close a path to ground for
the Instrument Cluster when a door is opened. The
passenger front door is connected in a parallel-series
circuit between ground and the Instrument Cluster,
while the driver side front door ajar switch is con-
nected in series between ground and the Instrument
Cluster to provide a unique input. The Instrument
Cluster reads the switch status, then sends the
proper switch status messages to other electronic
modules over the Programmable Communications
Interface (PCI) data bus network. The door ajar
switches can be diagnosed using conventional diag-
nostic tools and methods. Refer to the Body section
under Doors for the Removal and Installation proce-
dures.
GLOVE BOX LAMP/SWITCH
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the glove box from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
GLOVE BOX - REMOVAL) for the procedures.
(3) Reach through the glove box opening and
behind the glove box lamp and switch mounting
bracket to access the instrument panel wire harness
connector on the glove box lamp and switch (Fig. 3).
(4) Disconnect the instrument panel wire harness
connector from the connector receptacle on the back
of the glove box lamp and switch unit.
(5) Reach through the glove box opening and
behind the glove box lamp and switch mounting
bracket to depress the retaining tabs on the top and
bottom of the glove box lamp and switch housing.
(6) While holding the retaining tabs depressed,
push the glove box lamp and switch unit out through
the hole in the mounting bracket on the instrument
panel glove box opening upper reinforcement.
(7) Remove the glove box lamp and switch unit
from the instrument panel.
Fig. 2 Dome Lamp
1 - SLIDE LAMP
Fig. 3 Glove Box Lamp and Switch Remove/Install
1 - WIRE HARNESS CONNECTOR
2 - DASH BOARD
3 - GLOVE BOX SWITCH/LIGHT
DRLAMPS/LIGHTING - INTERIOR 8L - 27
DOME LAMP (Continued)
Page 587 of 2627
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 section may be
required to restore proper compass operation.
TEMPERATURE DISPLAY
All the available overhead consoles on this model
include Temperature information. The temperature
displays the outside ambient temperature in whole
degrees. The temperature display can be toggled
from Fahrenheit to Celsius by selecting the desired
U.S./Metric option from the customer programmable
features. 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 electronic control modules, (CMTC, EVIC) mem-
ory. When the ignition switch is turned to the On
position again, the electronic module will display the
memory temperature 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. This sensor is mounted out-
side the passenger compartment near the front and
center of the vehicle, and is hard wired to the Front
Control Module (FCM). The FCM sends temperature
status messages to the module over the J1850 PCI
data bus circuit. For more information on the ambi-
ent temperature sensor, refer to Ambient Tempera-
ture Sensor later in this section.
Following are general descriptions of the major
components used in the overhead console. Refer to
Wiring Diagrams for complete circuit schematics.
OPERATION
Refer to the vehicle Owner's Manual for specific
operation of each overhead console and its systems.
DIAGNOSIS AND TESTING - OVERHEAD
CONSOLE
If the problem with the overhead console is an
inaccurate or scrambled display, refer toSELF-DI-
AGNOSTIC TESTlater in this text. If the problem
with the overhead console is incorrect Vacuum Fluo-
rescent Display (VFD) dimming levels, use a DRB
IIItscan tool and the proper Diagnostic Procedures
manual to test for the correct dimming message
inputs being received from the Body Control Module
(BCM) or Front Control Module (FCM) over the
J1850 Programmable Communications Interface
(PCI) data bus circuit. If the problem is a no-display
condition, use the following procedure. For complete
circuit diagrams, refer toOverhead Consolein the
Wiring Diagrams section of the service manual.
(1) Remove the overhead console from the head-
liner (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - REMOVAL).
(2) Check for battery voltage at the overhead con-
sole electrical connector. Refer to Wiring for connec-
tor information. If OK, go to Step 3. If not OK, Check
for battery voltage at the appropriate B(+) fuse in the
integrated power module, repair the open fused B(+)
circuit as required.
(3) Turn the ignition switch to the On position.
Check the fused ignition switch output circuit(s) at
the overhead console electrical connector. If OK, go to
Step 4. If not OK, repair the open or shorted circuit
as required.
(4) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Check for continuity between the ground circuit cav-
ity of the overhead console electrical connector and a
good ground. There should be continuity. If OK, refer
toSELF-DIAGNOSTIC TESTbelow for further
diagnosis of the electronics module and the J1850
PCI data bus circuit. If not OK, repair the open
ground circuit as required.
Fig. 1 DR OVERHEAD CONSOLE ± EVIC
8M - 2 MESSAGE SYSTEMSDR
OVERHEAD CONSOLE (Continued)
Page 588 of 2627
SELF-DIAGNOSTIC TEST
A self-diagnostic test is built-in to the module to
determine that the electronics module is operating
properly, and that all the J1850 PCI data bus mes-
sages are being received for proper operation. To per-
form the self-diagnostic test proceed as follows:
(1) With the ignition switch in the Off position,
simultaneously depress and hold theSTEP and
RESET buttons.
(2) Turn the ignition switch to the On position.
(3) Following completion of the test, the electronics
module will display one of the following messages:
a.Pass Self Test (EVIC only), PASS (CMTC)-
The electronics module is working properly.
b.Failed Self Test (EVIC only), FAIL (CMTC)-
The electronics module has an internal failure. The
electronics module is faulty and must be replaced.
c.Failed J1850 Communication (EVIC only),
BUS (CMTC)- The electronics module is not receiv-
ing proper message input through the J1850 PCI
data bus circuit. This can result from one or more
faulty electronic modules in the vehicle, or from a
faulty PCI data bus. The use of a DRB IIItscan tool
and the proper Diagnostic Procedures manual are
required for further diagnosis.
NOTE: If the compass functions, but accuracy is
suspect, it may be necessary to perform a variation
adjustment. This procedure allows the compass
unit to accommodate variations in the earth's mag-
netic field strength, based on geographic location.
Refer to Compass Variation Adjustment in the Stan-
dard Procedures section of this group.
NOTE: If the compass reading displays dashes, and
only ªCALº appears in the display, demagnetizing
may be necessary to remove excessive residual
magnetic fields from the vehicle. Refer to Compass
Demagnetizing in the Standard Procedures section
of this group.
STANDARD PROCEDURE
STANDARD PROCEDURE - READING/
COURTESY LAMP REPLACEMENT
(1) Open hood, disconnect and isolate the negative
battery cable.
(2) Remove the reading/courtesy lamp lens. Using
a trim stick, gently pry the forward edge of the read-
ing/courtesy lamp lens outward.
(3) Remove the reading/courtesy lamp socket from
the overhead console. Rotate the reading/courtesy
lamp socket one quarter turn counter clockwise.
(4) Remove the lamp and socket assembly.(5) Reverse the above procedure to install.
STANDARD PROCEDURE - MODULE LENS
REPLACEMENT
(1) Remove the overhead console (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE -
REMOVAL).
(2) Remove the electronics module from the over-
head console. Refer to the procedure later in this sec-
tion.
(3) Unsnap the lens from the module and replace
lens as necessary.
STANDARD PROCEDURE - MODULE LAMP
REPLACEMENT
(1) Remove the overhead console (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE -
REMOVAL).
(2) Using a flat blade screwdriver twist out socket/
lamp (Fig. 2).
(3) Replace lamp(s) as necessary.
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.
Fig. 2 Top of Overhead Console
1 - OVERHEAD CONSOLE HOUSING
2 - EVIC/CMTC MODULE
3 - ILLUMINATION LAMPS
4 - MODULE RETAINING SCREWS
DRMESSAGE SYSTEMS 8M - 3
OVERHEAD CONSOLE (Continued)
Page 592 of 2627
NOTE: If a new module has been installed, the com-
pass will have to be calibrated and the variance set.
Refer to Compass Variation Adjustment and Com-
pass Calibration in the Standard Procedures sec-
tion of this group for the procedures.
ELECTRONIC VEHICLE INFO
CENTER
DESCRIPTION
The Electronic Vehicle Information Center (EVIC)
is a module located in the overhead console on some
models. The EVIC module features a large Vacuum
Fluorescent Display (VFD) screen for displaying
information, and back-lit push button switches
labeled C/T (compass/temperature), RESET, STEP,
and MENU.
The EVIC module contains a central processing
unit and interfaces with other electronic modules in
the vehicle over the Programmable Communications
Interface (PCI) J1850 data bus circuit. The PCI data
bus circuit allows the sharing of sensor information.
This helps to reduce wire harness 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 capabil-
ities.The EVIC ªMenuº push button provides the vehicle
operator with a user interface, which allows the
selection of several optional customer programmable
electronic features to suit individual preferences.
Refer toELECTRONIC VEHICLE INFORMA-
TION CENTER PROGRAMMINGin the Standard
Procedures section of this group for more information
on the customer programmable feature options.
If the vehicle is equipped with the optional univer-
sal transmitter transceiver, the EVIC will also dis-
play messages and an icon indicating when the
universal transmitter transceiver is being trained,
which of the three transmitter buttons is transmit-
ting, and when the transceiver is cleared.
Data input for all EVIC functions, including VFD
dimming level, is received through the J1850 PCI
data bus circuit. The EVIC module uses its internal
programming 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 DRB IIItscan tool and the proper
Diagnostic Procedures manual are recommended for
further testing of the EVIC module and the J1850
PCI data bus circuit.
The EVIC module cannot be repaired, and is avail-
able for service only as a unit. If any part is faulty or
damaged, the complete EVIC module must be
replaced.
OPERATION
The Electronic Vehicle Information Center is wired
to both constant 12v and ignition switched sources of
battery current so that some of its features remain
operational at any time, while others may only oper-
ate with the ignition switch in the On position. When
the ignition switch is turned to the On position, the
EVIC module display will return to the last function
being displayed before the ignition was turned to the
Off position.
The compass/temperature display is the normal
EVIC display. With the ignition switch in the On
position, momentarily depressing and releasing the
C/T (compass/temperature) push button switch will
cause the EVIC to return to the compass/tempera-
ture display mode from any other mode. While in the
compass/temperature display mode, momentarily
depressing and releasing the Step push button will
step through the available trip computer display
options.
The EVIC trip computer features several functions
that can be reset. The functions that can be reset
are: average fuel economy, trip odometer and elapsed
time. With the ignition switch in the On position and
with one of the functions of the trip computer that
can be reset currently displayed, depressing the
Fig. 5 OVERHEAD CONSOLE MODULE REMOVAL
1 - COMPASS MINI-TRIP COMPUTER MODULE
2 - OVERHEAD CONSOLE
DRMESSAGE SYSTEMS 8M - 7
COMPASS/MINI-TRIP COMPUTER (Continued)
Page 593 of 2627
Reset push button twice within three seconds will
perform a global reset, and all of the trip computer
information that can be reset will be reset to zero.
With the ignition switch in the On position and the
function that is to be reset currently displayed,
momentarily depressing and releasing the Reset
push button once will perform a local reset, and only
the value of the displayed function will be reset to
zero. A global or local reset will only occur if the
function currently displayed is a function that can be
reset. The distance to service function can also be
reset using the local reset method, but it will reset
back to the Service Interval distance that is set in
the EVIC programmable features mode. Refer to
ELECTRONIC VEHICLE INFORMATION CEN-
TER PROGRAMMINGin the Standard Procedures
section of this group for more information on setting
the Service Interval.
For more information on the features, control func-
tions and setting procedures for the EVIC module,
see the owner's manual in the vehicle glove box.
DIAGNOSIS AND TESTING - ELECTRONIC
VEHICLE INFORMATION CENTER
Electronic Vehicle Information Center (EVIC) data
is obtained from other electronic modules (CCN,
FCM, JTEC) on the J1850 Data Bus circuit. The
EVIC will display dashes (- -) for any of the screens
it did not receive the bus messages. The label corre-
sponding to the missing information will be lit. If no
EVIC data is displayed, check the J1850 Data Bus
circuit communications and the other modules. If the
brightness level is improper check the J1850 Data
Bus circuit.
Refer to Overhead Console Diagnosis and Testing
for instructions on performing a EVIC module Self-
Diagnostic Test. The DRB IIItis recommended for
checking the J1850 Data Bus circuit and other mod-
ules. Perform the EVIC self diagnosis before replac-
ing the EVIC module.
STANDARD PROCEDURE - ELECTRONIC
VEHICLE INFORMATION CENTER
PROGRAMMING
EVIC PROGRAMMING MODE
Some vehicles are equipped with a Electronic Vehi-
cle Information Center (EVIC) equipped overhead
console. The Electronic Vehicle Information Center
(EVIC) provides the vehicle operator with a user
interface, which allows the selection of several
optional customer programmable electronic features
to suit individual preferences. The EVIC must be
placed into its programming mode in order to view or
change the programmable features. To enter theEVIC programming mode and to view or change the
selected programmable features options, proceed as
follows:
(1) Turn the ignition switch to the On position.
(2) 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.
(3) Momentarily depress and release the Step push
button to step through the available options for the
programmable feature being displayed.
(4) 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.
(5) 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.
PROGRAMMABLE FEATURES
²LANGUAGE?- The options include English,
Francaise, Deutsch, Italiana, or Espanol. The default
is English. All EVIC display nomenclature, including
the trip computer functions, warning messages and
the programmable features appear in the selected
language.
²DISPLAY U.S. OR METRIC?- The options
include U.S. and M. The default is U.S. This feature
toggles the trip computer temperature, fuel economy
and odometer display readings between U.S. and
metric units of measure.
²SERVICE INTV. =- The options include from
3200 to 12000 kilometers in 800 kilometer incre-
ments (2000 to 6000 miles in 500 mile increments).
The default is 12000 kilometers (6000 miles). The
selected distance becomes the interval at which the
Perform Service warning message will be displayed
by the EVIC. If a new distance is selected, a second
programmable feature appears,RESET SERVICE
DISTANCE?- The options include No and Yes. The
default is Yes. When Yes is selected, the accumulated
distance since the last previous Perform Service
warning message will be reset to zero because the
service interval has been changed. When No is
selected, the distance until the next Perform Service
warning message is reduced by the accumulated dis-
tance since the last previous message.
²AUTO DOOR LOCKS?- The options include
Yes and No. The default is Yes. When Yes is selected,
all doors lock automatically when vehicle speed
reaches 25 kilometers-per-hour (15 miles-per-hour). If
YES is selected, a second programmable feature
8M - 8 MESSAGE SYSTEMSDR
ELECTRONIC VEHICLE INFO CENTER (Continued)