NOTE: If the EVIC module is being replaced, the tire
pressure monitoring system (if equipped) must be
retrained. (Refer to 22 - TIRES/WHEELS/TIRE PRES-
SURE MONITORING/SENSOR - STANDARD PROCE-
DURE)
INSTALLATION
(1) Position the Electronic Vehicle Information
Center (EVIC) module in the overhead console.
(2) Install the ten screws holding the EVIC module
in the overhead console.
(3) Install the overhead console (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE - INSTALLA-
TION).
(4) Connect the battery negative cable.
NOTE: If the EVIC module is being replaced, the tire
pressure monitoring system (if equipped) must be
retrained. (Refer to 22 - TIRES/WHEELS/TIRE PRES-
SURE MONITORING/SENSOR - STANDARD PROCE-
DURE).
NOTE: If a new EVIC module has been installed, the
compass will have to be calibrated and the variance
set. (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - STANDARD PROCEDURE - COMPASS CAL-
IBRATION).
COMPASS/MINI-TRIP
COMPUTER
DESCRIPTION
The Compass Mini-Trip Computer (CMTC) module
is located in the overhead console. The CMTC con-
sists of a electronic control module with a vacuum
fluorescent display (VFD) and function switches. The
CMTC consists of a electronic module that displays
compass, trip computer, and temperature features.
Actuating the STEP push button will cause the
CMTC to change mode of operation when the ignition
is ON. Example:
²Average miles per gallon (ECO)
²Distance to empty (DTE)
²Instant miles per gallon (ECO)
²Trip odometer (ODO)
²Elapsed time (ET)
²Blank
Actuating the C/T push button will cause the
CMTC to change to the Compass/Temperature dis-
play.
OPERATION
The Compass Mini-Trip Computer (CMTC) module
in the overhead console has buttons used to select
various functions. The CMTC selector buttons will
not operate until the ignition is in the RUN position.
When the ignition switch is first turned to the
RUN position the CMTC display;
²Blanks momentarily
²All segments of the VFD will light for one sec-
ond
²Blanks momentarily
²Returns to the last mode setting selected before
the ignition was last switched OFF.
DIAGNOSIS AND TESTING
COMPASS MINI-TRIP COMPUTER
Any diagnosis of the compass mini-trip com-
puter should begin with the use of the DRB IIIt
diagnostic tool. For information on the use of
the DRB IIIt, refer to the appropriate Diagnos-
tic Procedures information.
Compass Mini-Trip Computer (CMTC) data is
obtained from the Body Control Module (BCM) on
the Programmable Communications Interface (PCI)
Data Bus circuit. The CMTC will display dashes (- -)
for any of the screens it did not receive the bus mes-
sages. The label corresponding to the missing infor-
mation will be lit. If no CMTC data is displayed,
check the PCI Data Bus circuit communications and
the BCM. If the dimming level is improper check the
PCI Data Bus circuit.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove overhead console(Refer to 8 - ELEC-
TRICAL/OVERHEAD CONSOLE - REMOVAL).
(3) Remove the screws holding Compass Mini-Trip
Computer (CMTC) module in the overhead console.
(4) Remove CMTC module from the console assem-
bly.
INSTALLATION
(1) Position the compass mini-trip computer
(CMTC) module in the overhead console.
(2) Install the ten screws holding the CMTC mod-
ule in the overhead console.
(3) Install the overhead console (Refer to 8 -
ELECTRICAL/OVERHEAD CONSOLE - INSTALLA-
TION).
(4) Connect the battery negative cable.
8M - 10 OVERHEAD CONSOLERS
ELECTRONIC VEHICLE INFO CENTER (Continued)
²a rotary adjustment knob for temperature.
²a rotary adjustment for fan speed control.
AUTOMATIC TEMPERATURE CONTROL
Two different automatic temperature control (ATC)
heating-A/C systems are available for this model
depending on the market.
The Dual-Zone ATC system allows the driver and
front occupants to each select individual comfort tem-
peratures.
The Three-Zone ATC system allows both the driver
and front occupants and the rear intermediate occu-
pants to select individual comfort temperatures.
NOTE: Individual comfort temperatures are the per-
ceived temperature level at the individual seating
areas, NOT the actual passenger compartment air
temperature.
The ATC system includes a particulate air filter.
The filter element is the same size as the A/C evap-
orator to ensure ample capacity. A door at the base of
the HVAC housing below the glove box provides easy
access to the filter element.
The ATC computer utilizes integrated circuitry and
information carried on the programmable communi-
cations interface (PCI) data bus network to monitor
many sensors and switch inputs throughout the vehi-
cle. In response to those inputs, the internal circuitry
and programming of the ATC computer allow it to
control electronic functions and features of the ATC
system. The inputs to the ATC computer are:
²Vehicle Speed/Engine RPM± The ATC com-
puter monitors engine rpm, vehicle speed and mani-
fold absolute pressure information from the
powertrain control module (PCM).
²Coolant Temperature± ATC computer moni-
tors coolant temperature received from the PCM and
converts it to degrees Fahrenheit.
²Ambient Temperature± ATC computer moni-
tors ambient temperature from the compass mini trip
computer (CMTC) and converts it to degrees Fahren-
heit.
²Engine Miscellaneous Sensor Status±ATC
computer monitors A/C disable information from the
PCM.
²Refrigerant Pressure± ATC computer moni-
tors barometric pressure, intake air temperature,
high side pressure and methanol content as broad-
cast by the PCM.
²Door Ajar Status± The ATC computer moni-
tors driver front door, passenger front door, left rear
door, right rear door and liftgate ajar information, as
identified by the body control module (BCM), to
determine if all in-car temperatures should be main-
tained.²Dimming± The ATC computer monitors dim-
ming status from the BCM to determine the required
level of brightness and will dim accordingly.
²Vehicle Odometer± The ATC computer moni-
tors the vehicle odometer information from the BCM
to prevent flashing the vacuum-flourescent (VF) dig-
ital display icons if the manual motor calibration or
manual cool down tests have failed. Flashing of the
display icons will cease when the vehicle odometer is
greater than 3 miles.
²English/Metric± The ATC computer monitors
the English/Metric information broadcast by the
CMTC. The set temp displays for both the front and
rear control heads will be set accordingly.
²Vehicle Identification Number± The ATC
computer monitors the last eight characters of the
VIN broadcast by the PCM and compares it to the
information stored in EEPROM. If it is different, the
new number will be stored over the old one and a
motor calibration shall be initiated.
²A/C System Information± The ATC computer
will send a message for evaporator temperature too
low, fan blower relay status, evaporator sensor fail-
ure, rear window defogger relay and A/C select.
FRONT CONTROL PANEL
The front A/C-heater control and integral computer
is mounted in the instrument panel and contains:
²a power button which allows the system to be
completely turned off. The display is blank when the
system is off.
²a rocker switch that selects a cool-down rate.
LO-AUTO or HI-AUTO are displayed when the sys-
tem is in automatic operation.
²three rocker switches that select comfort temper-
atures from 15É to 30É C (59É to 85É F), which are
shown in the VF digital display. If the set temp is 15É
C (59É F) and the down button is pressed, the set
temp value will become 13É C (55É F) but the display
will show LO. If the set temp is 29É C (85É F) and the
up button is pressed, the set temp value will become
32É C (90É F) but the display will show HIGH. Tem-
peratures can be displayed in either metric or Fahr-
enheit, which is controlled from the overhead console.
²an air conditioning button that allows the com-
pressor to be turned off. A Snowflake symbol is illu-
minated when air conditioning is on, whether under
manual or automatic control.
²an air recirculation button. A Recirculation sym-
bol appears in the display when the button is
pressed, or when the system exceeds 80 percent recir-
culated air under automatic control due to high air
conditioning demand.
²a rear window defogger on/off switch. A graphic
symbol shows when the defroster is on.
RSHEATING & AIR CONDITIONING24-3
HEATING & AIR CONDITIONING (Continued)