secured to the floor under the Driver seat and
receives power from the Fuse Block No. 1. When-
ever the ignition key is turned to the run or start
position, the ACM performs a system test. The ACM
cannot be repaired or adjusted.
The microprocessor in the ACM monitors the
internal and external airbag system electrical cir-
cuits to determine the system readiness. When a
monitored system is determine to be out of range,
the ACM will set both active and stored diagnostic
trouble codes (DTC). The ACM also contains an
energy-storage capacitor. This capacitor stores
enough electrical energy to deploy the front airbag
components for two seconds following a battery
disconnect or failure during an impact.
The Accelerometer in the ACM is used to sense
the rate of vehicle deceleration, provide verification
of the direction and severity of an impact. When the
preprogrammed conditions are met, the ACM sends
an electrical signal to deploy the appropriate front
airbag system components and a deployment noti-
fication.
To provide an accident response notification, the
ACM is hardwired to the Central Timer module
(CTM) and Engine Control Module (ECM). When a
deployment occurs the ACM provides a 50ms 10.0
volt pulse to the CTM and ECM. When the Accident
Report notification signal is received the CTM un-
locks the door locks and the ECM stalls the engine.
The Accident signal will set a DTC in the CTM and
the door locks will not work until the DTC has been
erased. The ECM will set a DTC if the Accident
Report circuit is shorted to battery voltage. The
ACM saves the deployment record and after three
deployments the ACM must be replaced. The
DRBIIItcan be used to test the Accident Report
Notification feature: select the SYSTEM TEST from
the ACM main menu. Then select the Analog Crash
Output System Test.
The ACM is hardwired to the Instrument Cluster
(MIC) to control Warning Indicator (SRS indicator).
When DTCs becomes activate, the ACM illuminates
the Warning Indicator by pulling the indicator
circuit low. The SRS indicator is the only point at
which the customer can observe symptoms of a
system malfunction.
As part of the system test the ACM illuminates
the Warning Indicator on for 4.0 second bulb test.
After the lamp check, if the indicator turns off, it
means that the ACM has checked the system and
found it to be free of discernible malfunctions.
NON-CRITICAL DTCs
If the lamp comes on and stays on for a period
longer than 4.0 seconds (about 10.0 seconds) is
usually a stored DTC (intermittent problem) in the
system.
CRITICAL DTCs
DTCs that could lead to a condition where the
safety devises may not deploy or incorrectly deploy.
In the event of such a DTC, the safety of the vehicle
occupants can no longer be guaranteed. If the lamp
remains on, there could be an active DTC in the
system. Some DTCs, Internal Module and squib
DTCs, will keep the indicator illuminated even if
the codes are no longer active.
ACM NOT CONFIGURED FOR PASSENGER
AIRBAG AND TENSIONER
If after replacing the ACM the Airbag Warning
Indicator flashes continuously the ACM must be
configured for the Passenger Airbag and Tensioner.
Select Miscellaneous from the ACM main menu and
configure the Passenger Airbag Tensioner squibs.
WARNING:THE AIRBAG SYSTEM IS A
SENSITIVE, COMPLEX ELECTROMECHANICAL
UNIT. BEFORE ATTEMPTING TO DIAGNOSE OR
SERVICE ANY AIRBAG SYSTEM OR RELATED
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENTS YOU MUST
FIRST DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE. WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR
TO DISCHARGE BEFORE FURTHER SYSTEM
SERVICE. THIS IS THE ONLY SURE WAY TO
DISABLE THE AIRBAG SYSTEM. FAILURE TO
DO THIS COULD RESULT IN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, NEVER STRIKE OR KICK THE
AIRBAG CONTROL MODULE, AS IT CAN
DAMAGE THE IMPACT SENSOR OR AFFECT
ITS CALIBRATION.
WARNING: IF AN AIRBAG CONTROL
MODULE IS ACCIDENTALLY DROPPED
DURING SERVICE, THE MODULE MUST BE
SCRAPPED AND REPLACED WITH A NEW
UNIT. FAILURE TO TAKE THE PROPER
PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND
PERSONAL INJURY OR DEATH.
3.1.1 DRIVER AIRBAG
The airbag protective trim cover is the most
visible part of the driver side airbag system. The
airbag is mounted directly to the steering wheel.
Located under the trim cover are the airbag cushion
and the airbag cushion supporting components.
2
GENERAL INFORMATION
Static Heater Signal
A status of9ON9indicates that the heater module
sees the9Stationary Heating Mode ON9signal after
switching on the heater with the heater timer or the
auxiliary heater switch. A status of9OFF9indicates
that the9Stationary Heating Mode ON9signal is
not present at the heater module.
Heater Booster Mode Signal
A status of9ON9indicates that the heater module
sees the9Heater Booster Mode ON9signal after
switching on the heater with the auxiliary heater
switch. A status of9OFF9indicates that the9Heater
Booster Mode ON9signal is not present at the
heater module.
3.4 INSTRUMENT CLUSTER
The Instrument Cluster has easy-to-read instru-
ments, is capable of CAN bus communication and
provides a diagnostic function. The Instrument
Cluster with analog speedometer, tachometer, fuel
and coolant temperature gauges comes in two ver-
sions.
²Speedometer with outer miles-per-hour (mph)
scale and inner kilometers-per-hour (km/h) scale.
Coolant temperature is indicated in Fahrenheit
(for US).
²Speedometer with outer kilometers-per-hour
(km/h) scale and inner miles-per-hours (mph)
scale. Coolant temperature is indicated in de-
grees Celsius (for Canada).
Below the speedometer, there is a LCD multi-
function indicator in clear view of the driver. Warn-
ing and indicator lights (based on colored light
emitting diodes) are located in the bottom of the
instrument cluster with the exception of the turn
signal indicator lights, ASR warning light and re-
serve fuel warning light. The warning lights for the
seat belt usage and parking brake/brake fluid level
are located in the line above the bottom line. The
indicator that illuminates up when the parking
brake is applied or the brake fluid level is low is
different for U.S. and Canada.
When the key is turned to the 2nd position in the
ignition, the function of the following indicator
lights is checked automatically: High Beam ON,
Preheating, airbag malfunction. In case of a broken
LED of the airbag malfunction light, the seat belt
usage warning light will flash for 6 seconds after
the function check is finished. The Instrument
Cluster is operated with the help of 4 buttons
located below the multifunction indicator. The back-
lighting for the instrument cluster uses yellow
LED's and can be adjusted electronically to daylight
and darkness.The instrument cluster includes a warning
buzzer, which sounds (in addition to a warning light
in some cases) when:
²The headlights are on with the ignition off and
the door opened.
²The driver 's seat belt is not fastened with the
ignition on.
²The key is in the ignition and the door is open.
²Critical ASSYST information is displayed in the
multifunction indicator.
3.5 POWER DOOR LOCKS/RKE
3.5.1 CENTRAL LOCKING
The Central Locking System locks all vehicle
doors if any door is locked from the inside or
mechanically locked with the key from the outside.
However, unlocking any door, in that manner, will
only unlock that particular door. The Master Door
Lock Switch on the dash enables the operator to
lock/unlock all doors. By pressing the top of the
rocker type switch once, all doors will lock. Pressing
the switch again will unlock all doors. Pressing the
lower part of the switch once will lock all doors
except the driver door. Pressing the lower part
again will unlock all doors except the driver door. If
the Central Locking System automatically unlocks
after the vehicle was attempted to be locked, at
least one door is not properly closed.
There are two LED indicators in the Master Door
Lock Switch. The left indicator is for the driver door
and the right indicator is for all passenger/cargo
doors. These will indicate if a door is ajar or if the
doors are locked. The door ajar switches are part of
the door lock motor and are mounted in the door
latch assembly.
Inside each door lock motor there is a command
switch. The command switch is operated by the
plunger and signals any change in the lock status,
locked or unlocked. Each command switch is wired
to the Central Timer Module (CTM) sometimes
referred to as the Central Locking Module. If all
doors are closed and are unlocked, and any door is
locked by the key or the interior handle, thereby
changing the command switch, all doors will be
locked. If one of the door lock motors does not reach
the end position after a locking command, it will be
detected by the CTM (command switch not in
9Locked9position) and the vehicle will be unlocked.
3.5.2 REMOTE KEYLESS ENTRY (RKE)
The SKREEM is a combination of the Remote
Keyless Entry Module and the SKIM (Sentry Key
Immobilizer Module). It is located behind the In-
strument Cluster and has an antenna that goes up
9
GENERAL INFORMATION
the A-pillar. The SKREEM receives radio messages
from the RKE transmitter (fob) and sends com-
mands via the RKE Interface circuit to the CTM. If
the vehicle is equipped with VTSS, the Security
System Module will be connected in series between
the SKREEM and the CTM.
Confirmation of the RKE Lock/Unlock state is
accomplished via the turn signals. When the vehicle
is locked via RKE the turn signals will flash three
times. When it is unlocked via RKE, the turn
signals will flash one time. If the vehicle has been
unlocked via RKE and no door is opened within 40
seconds, the entire vehicle will be locked again
automatically.
If a transmitter (fob) is operated more than 255
times in succession beyond the range of the receiver
(SKREEM), the RKE portion of the key will become
inoperative. In order to put it back in synchroniza-
tion it will be necessary to have ALL the other
transmitters that are used with this vehicle avail-
able and follow the following procedure:
1. Cycle the ignition on and off 2 times within 6
seconds (leave in off position).
2. Press the lock or unlock button of the disabled
transmitter within 3 seconds of turning the
ignition off.
3. Press any button (lock or unlock) 3 more times
within 6 seconds.
4. Wait 10 seconds.
5. Press any button of ALL other transmitters
belonging to this vehicle at least once within
the next 20 seconds.
For problems related to the Immobilizer function
of the SKREEM, see Service Information.
3.5.3 AUTO DOOR LOCKS
Whenever the engine is started, the CTM receives
a message to lock all doors except the drivers door.
This is accomplished through the D+ Relay. The D+
Relay is controlled by the Instrument Cluster which
receives a command from the ECM that the engine
is running. This relay supplies power to the CTM
(for auto locking), the daytime running lamps and
the rear window defogger.
3.5.4 ACCIDENT RESPONSE
The CTM is hardwired to the Airbag Control
Module through the Enhanced Accident Report
Driver circuit. Anytime the vehicle airbags are
deployed, the CTM will unlock all doors and a
9Crash9DTC will be stored in memory. The door
locks will be inoperative until that code is cleared. If
the vehicle is severly jarred, but not enough to
deploy the airbags, it is possible that the DTC could
be set and therefore the door locks would be inop-
erable. Whenever the door locks are not opera-tional, use the DRBIII and check DTC's . If the code
9ACM has unlocked the doors9appears, use the
DRBIII and erase it.
3.6 VEHICLE THEFT SECURITY SYSTEM
(VTSS)
The Security System Module (SSM) is located
under the driver's seat. The SSM communicates
with the DRBIII over the K-line. If equipped the
Vehicle Theft Security System will monitor the
following:
²door jamb switches
²hood ajar switch
²ignition switch
²interior of the vehicle for movement
²longitudinal and transverse movement of the
vehicle
²rear defogger grids for glass breakage
²trailer connector
To arm the system the hood and all of the doors
must be closed when the vehicle is locked with the
RKE transmitter or with the use of the key in the
driver door. If the key is used, it must be held in the
lock position for 2 seconds. When the system is first
activated, the hazard lamps will flash 3 times. Also
with the system armed, the Towing/Intrusion Sen-
sor On/Off Switch indicator will flash to indicate an
armed system. To disarm the system use the RKE
or the driver door lock cylinder. Unlocking and
opening one of the other doors with the system
armed will trip the vehicle theft security system.
Interior monitoring is done by the use of an
Intrusion Sensor located in the front headliner and
with one or two sensors in the ceiling of the cargo
area depending on how the vehicle is equipped.
Monitoring of the interior of the vehicle will begin
after the system has been armed for 30 seconds. The
on/off switch located on the instrument panel can be
used to turn off this feature with the ignition switch
in either the Locked/Off or ACC position. The vehi-
cle tow-monitoring feature can also be switched off
using this switch. Re-locking the vehicle a second
time will reactivate these features.
If a trailer is connected to the vehicle when the
system is armed, the SSM will sense a resistance
change on the turn signal circuits if the trailer
harness becomes disconnected and will trip the
alarm.
Tripping the vehicle theft security system will
cause the hazard lamps to flash and the siren to
sound at 30-second intervals. The siren is equipped
with it's own self-contained battery. In the event the
vehicle's battery power is disconnected the siren
will continue to sound on it's own.
10
GENERAL INFORMATION
Symptom:
AIR OUTLET TEMP SENSOR HIGH OR OPEN (ACTIVE)
POSSIBLE CAUSES
AIR OUTLET TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
AUTOMATIC TEMPERATURE CONTROL (ATC)
AUTOMATIC TEMPERATURE CONTROL (ATC)
AIR OUTLET TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN
SENSOR GROUND CIRCUIT OPEN
AIR OUTLET TEMPERATURE SENSOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Air Outlet Temperature Sensor harness connector.
Turn the ignition on.
While back probing, measure the voltage between the Air Outlet Temperature Sensor
Signal circuit and the Sensor Ground circuit.
Is the voltage above 5.3 volts?All
Ye s!Go To 2
No!Go To 3
2 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Air Outlet Temperature Sensor harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Turn the ignition on.
Measure the voltage of the Air Outlet Temperature Sensor Signal circuit.
Is the voltage above 0.2 volts?All
Ye s!Repair the Air Outlet Temperature Sensor Signal circuit for a
short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Air Outlet Temperature Sensor harness connector.
Turn the ignition on.
While back probing, measure the voltage between the Air Outlet Temperature Sensor
Signal circuit and Sensor Ground circuit in the Automatic Temperature Control
(ATC) C1 harness connector.
Is the voltage above 4.5 volts?All
Ye s!Go To 4
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
134
HEATING & A/C
TEST ACTION APPLICABILITY
4 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Disconnect the Air Outlet Temperature Sensor harness connector.
Measure the resistance of the Air Outlet Temperature Sensor Signal circuit between
the Automatic Temperature Control (ATC) C1 harness connector and the Air Outlet
Temperature Sensor harness connector.
Is the resistance below 5.0 ohms?All
Ye s!Go To 5
No!Repair the Air Outlet Temperature Sensor Signal circuit for an
open.
Perform BODY VERIFICATION TEST - VER 1.
5 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Disconnect the Air Outlet Temperature Sensor harness connector.
Measure the resistance of the Sensor Ground circuit between the Automatic
Temperature Control (ATC) C1 harness connector and the Air Outlet Temperature
Sensor harness connector.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Air Outlet Temperature Sensor in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No!Repair the Sensor Ground circuit for an open.
Perform BODY VERIFICATION TEST - VER 1.
135
HEATING & A/C
AIR OUTLET TEMP SENSOR HIGH OR OPEN (ACTIVE) ÐContinued
Symptom:
AIR OUTLET TEMP SENSOR SHORTED LOW (ACTIVE)
POSSIBLE CAUSES
AIR OUTLET TEMPERATURE SENSOR
AIR OUTLET TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
AIR OUTLET TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND CIRCUIT
AUTOMATIC TEMPERATURE CONTROL (ATC)
AIR OUTLET TEMPERATURE SENSOR SIGNAL CIRCUIT SHORT TO SENSOR GROUND CIR-
CUIT
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Air Outlet Temperature Sensor harness connector.
Turn the ignition on.
With the DRBIIIt, record and erase Automatic Temperature Control DTCs.
Turn the ignition off, wait 5 seconds, then turn the ignition on.
With the DRBIIIt, read the Automatic Temperature Control DTCs.
Does the DRBIIItdisplay: AIR OUTLET TEMP SENSOR HIGH OR OPEN?All
Ye s!Replace the Air Outlet Temperature Sensor in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition off.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Measure the resistance between ground and the Air Outlet Temperature Sensor
Signal circuit.
Is the resistance below 10k ohms?All
Ye s!Repair the Air Outlet Temperature Sensor Signal circuit for a
short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 3
3 Turn the ignition off.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Measure the resistance between the Air Outlet Temperature Sensor Signal circuit
and the Ground circuit.
Is the resistance below 10k ohms?All
Ye s!Repair the Air Outlet Temperature Sensor Signal circuit for a
short to the Ground circuit.
Perform BODY VERIFICATION TEST - VER 1.
No!Go To 4
136
HEATING & A/C
TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the Air Outlet Temperature Sensor harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Measure the resistance between the Air Outlet Temperature Sensor Signal circuit
and the Sensor Ground circuit.
Is the resistance below 10k ohms?All
Ye s!Repair the Air Outlet Temperature Sensor Signal circuit for a
short to the Sensor Ground circuit.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
137
HEATING & A/C
AIR OUTLET TEMP SENSOR SHORTED LOW (ACTIVE) ÐContinued
Symptom:
EVAP TEMP SENSOR HIGH OR OPEN (ACTIVE)
POSSIBLE CAUSES
EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
AUTOMATIC TEMPERATURE CONTROL (ATC)
AUTOMATIC TEMPERATURE CONTROL (ATC)
EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN
SENSOR GROUND CIRCUIT OPEN
EVAPORATOR TEMPERATURE SENSOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Evaporator Temperature Sensor harness connector.
Turn the ignition on.
While back probing, measure the voltage between the Evaporator Temperature
Sensor Signal circuit and the Sensor Ground circuit.
Is the voltage above 5.3 volts?All
Ye s!Go To 2
No!Go To 3
2 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Evaporator Temperature Sensor harness connector.
Disconnect the Automatic Temperature Control (ATC) C1 harness connector.
Turn the ignition on.
Measure the voltage of the Evaporator Temperature Sensor Signal circuit.
Is the voltage above 0.2 volts?All
Ye s!Repair the Evaporator Temperature Sensor Signal circuit for a
short to voltage.
Perform BODY VERIFICATION TEST - VER 1.
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
NOTE: Check connectors - Clean/repair as necessary.
Disconnect the Evaporator Temperature Sensor harness connector.
Turn the ignition on.
While back probing, measure the voltage between the Evaporator Temperature
Sensor Signal circuit and Senor Ground circuit in the Automatic Temperature
Control (ATC) C1 harness connector.
Is the voltage above 4.5 volts?All
Ye s!Go To 4
No!Replace the Automatic Temperature Control (ATC) in accordance
with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
156
HEATING & A/C