
seconds instead of 5, the CMTC will set the
variance to 8 and enter the fast calibration
mode.
3. The VAR light will come on and the last variance
setting will be displayed.
4. Press the STEP button to set the zone number.
5. Press the US/M button and resume normal op-
eration.
NOTE: Do not attach any magnetic device
such as a magnetic CB antenna to the
vehicle. This can cause the compass to give
false readings.
3.15 POWER DOOR LOCK SYSTEM
When the BCM receives input for a lock request
from a door lock switch, RKE or cylinder lock switch
(only with VTSS), it will turn the lock driver on for
a specified time of 375 msec. If the request is there
beyond 375 msec, the BCM considers the door lock
signal stuck. Once a door lock or unlock signal is
stuck for longer than 10 seconds, the BCM will set
a trouble code and the signal input is ignored until
the stuck condition disappears. The door lock
switches provide a variable amount of resistance
thereby dropping the voltage of the multiplexed
(MUX) circuit and the BCM will respond to that
command.
3.15.1 SLIDING DOOR MEMORY LOCK
When the BCM receives an input for a lock
request and a sliding door is open, the BCM will
turn on the lock driver as described above, and will
turn it on again when all sliding doors are closed.
NOTE: If the BCM receives an unlock input before
a sliding door is closed, this will cancel the memory
lock.
3.15.2 DOOR LOCK INHIBIT
When the key is in the ignition and in any
position and either front door is open, the door lock
switches LOCK functions are disabled. The UN-
LOCK functions are still functional. This protects
against locking the vehicle with the keys still in the
ignition. The RKE key fob will still lock the doors as
usual. This allows the driver to lock the vehicle with
the engine running for warm up.
3.15.3 AUTOMATIC DOOR LOCKS
This feature can be enabled or disabled by using
either the DRBIIItor the customer programming
method. When enabled all the doors will lock when
the vehicle reaches a speed of 18 MPH (29 KMH)
and all the doors are closed. If a door is opened and
the vehicle slows to below 18 MPH (29 KMH), thedoor locks will operate again once all doors are
closed and the speed is above 15 MPH (24 KMH).
3.15.4 REMOTE KEYLESS ENTRY (RKE)
The body control module interfaces with the RKE
module via a one-way serial bus interface. The RKE
module is not on the PCI bus. The RKE module
sends a 0-5 volt pulse width signal to the BCM
depending on which button on the transmitter was
pressed. The BCM controls the door lock/unlock
functions and the arming/disarming of the Vehicle
Theft Security System (if equipped) and the activa-
tion of illuminated entry. The BCM will also send
the appropriate messages to the Power Sliding
Doors and Power Liftgate modules. The Intelligent
Power Module (IPM) activates the park lamps,
headlamps, and horn for horn chirp when sent the
appropriate message from the BCM as received
from the RKE transmitter. When a one-button
press is made for unlock, both driver side doors will
unlock and the front and rear turn signal will flash.
When a second press is initiated (within 5 seconds
of the first) both passenger doors will unlock and all
four turn signals will flash.
The RKE module is capable of retaining up to 4
individual access codes (4 transmitters). If the
PRNDL is in any position except park, the BCM will
ground the interface thereby disabling the RKE.
The 2 button transmitter will have 2-CR2016
batteries in series. The 5 button transmitter will
have 1-CR2016 battery. The minimum battery life
should be approximately 4.7 years based on 20
transmissions a day at 84ÉF (25ÉC). Using the
DRBIIItand selecting RKE FOB Test can test the
transmitter.
The RKE module can be programmed via the
DRBIIItor the customer programming method.
The BCM will only allow programming mode to be
entered when the ignition is in the on position, the
PRNDL is in park position, and the VTSS (if
equipped) is in the disarmed mode.
3.16 POWER FOLDING MIRRORS
The power folding mirrors are powered to two
positions: folded and unfolded. The driver may
choose fold or unfold with a switch that is located on
the right side of the steering column. The folding
mirror switch grounds a sense wire that comes from
the Body Control Module when it is placed in the
fold position. The mirrors will move to the position
designated by the switch whether the ignition
switch is the On or Off position and both front doors
are closed. When the Power Folding Mirror switch
is left in the fold position during a vehicle exit the
mirrors will automatically unfold then refold after
both front doors are closed. This is to prevent mirror
contact with either front door when opened. When
24
GENERAL INFORMATION

opening either front door, the Body Control Module
will unfold the mirrors in the following manner
depending on which front door is opened. If the
driver door is opened, only the driver side mirror
will unfold. If the passenger door is opened, both
mirrors will unfold. The passenger mirror is pre-
vented from unfolding when the driver 's door is
opened by the Passenger Folding Mirror Relay,
which opens the driver circuit to the passenger side
mirror.
3.17 POWER LIFTGATE SYSTEM
3.17.1 POWER LIFTGATE
The power liftgate (PLG) system is activated
through the use of the following: remote keyless
entry (RKE), overhead console switches, outside
liftgate handle switch or the DRBIIIt. These inputs
are hardwired to the body control module (BCM)
and can be monitored with a diagnostic tool. The
BCM will send the message via PCI bus to the
power liftgate module (PLGM). The liftgate must be
in the full open or full closed position to operate.
Once the BCM sends a button activation message to
the PLGM, the module shall read all inputs, out-
puts and vehicle conditions to determine whether it
shall open, close or inhibit the PLG operation. Once
the PLGM determines the vehicle conditions are
safe for operation, the PLGM will initiate a chime
for 2 seconds prior to the liftgate activation and 2
seconds during the open or close cycle.
During an opening or closing cycle, the PLGM can
detect an obstacle present should it meet sufficient
resistance by the hall effect sensors (integrated in
the gear motor assembly GMA).
During an open cycle, multiple liftgate activa-
tions (RKE, overhead console, B pillar) are ignored
until the liftgate reaches the full open position.
However, during a close cycle, a 2nd liftgate activa-
tion (RKE, overhead console, B pillar) will reverse
the liftgate to the full open position.
If the engine is cranked during a power open/close
the PLG will pause then resume after engine crank-
ing. In addition, if the vehicle is placed in gear
during an open cycle, the PLG shall reverse direc-
tion and begin closing. If the vehicle is placed in
gear during a closing cycle, the PLG shall continue
closing until fully closed. If the outside handle is
activated during an open cycle, the PLG will become
a full manual liftgate. If the outside handle is
activated during a close cycle, the PLG shall reverse
direction of travel to the full open position.
3.17.2 DIAGNOSTIC FEATURES
The PLG can be flashed on vehicle via PCI bus
with a DRBIIItdiagnostic tool. The DRBIIItcanread all inputs, actuate all outputs, read module
information, and read diagnostic trouble codes. As a
reminder, some DTC's can be set during normal
PLG operation.
3.17.3 SYSTEM INHIBITORS
1. Battery voltage too high or too low (above 16V,
below 9.5V)
2. Vehicle in gear
3. Vehicle speed > 0 mph/km/h
4. Outside temperature too high, above 143ÉF
(62ÉC) or too low, below -12ÉF (-24ÉC).
5. O/H console lockout will inhibit the B pillar
switches only.
6. Liftgate locked will inhibit all interior switches
from opening (overhead console). A locked lift-
gate can be power closed.
7. Pinch Sensor switch stuck shall inhibit the
power close feature.
3.18 POWER SLIDING DOOR SYSTEM
3.18.1 POWER SLIDING DOOR
The Power Sliding Door (PSD) system is acti-
vated through the use of the following: Remote
Keyless Entry (RKE), overhead console switches, B
pillar switches or the DRBIIIt. These inputs are
hardwired to the body control module (BCM) and
can be monitored with a diagnostic tool. The BCM
will send the message via PCI bus to the power
sliding door module (PSDM). The sliding door must
be in the full open or full closed position to operate.
Once the BCM sends a button activation message to
the PSDM, the module shall read all inputs, out-
puts and vehicle conditions to determine whether it
shall open, close or inhibit the PSD operation.
During an opening or closing cycle, the PSDM can
detect an obstacle present should it meet sufficient
resistance by the hall effect sensors (integrated in
the drive motor).
During an open cycle, multiple door activations
(RKE, overhead console, B pillar) are ignored until
the door reaches the full open position. However,
during a close cycle, a 2nd door activation (RKE,
overhead console, B pillar) will reverse the door to
the full open position.
If the engine is cranked during a power open/close
the PSD will pause then resume after engine crank-
ing. In addition, if the vehicle is placed in gear
during an open cycle, the PSD shall reverse direc-
tion and begin closing. If the vehicle is placed in
gear during a closing cycle, the PSD shall continue
closing until fully closed.
If the inside or outside handle is activated during
an open or close cycle, the PSD will become a full
25
GENERAL INFORMATION

manual sliding door. When the child lock out switch
is on, the B pillar switches are disabled.
There is only one part number for the power
sliding door module (PSDM). The driver sliding
door harness has an additional ground circuit which
will identify it as the driver side. This eliminates
the need for a left and a right side module.
3.18.2 DIAGNOSTIC FEATURES
The PSDM can be flashed on vehicle via PCI bus
with a DRBIIItdiagnostic tool. The DRBIIItcan
read all inputs, actuate all outputs, read module
information, and read diagnostic trouble codes. As a
reminder, some DTC's can be set during normal
PSD operation.
3.18.3 SYSTEM INHIBITORS
1. Battery voltage too high or too low (above 16V,
below 9.5V)
2. Vehicle in gear
3. Vehicle speed > 0 mph/km/h
4. Child locks enabled inhibit the B pillar switch
operation
5. O/H console lockout will inhibit the B pillar
switches
6. Doors locked will inhibit all interior switches
from opening (Overhead Console, B Pillar). A
locked sliding door can be power closed.
3.19 REAR WINDOW DEFOG/HEATED
MIRROR/FRONT WIPER DE-ICE
The defroster button located on the HVAC control
controls the rear window defogger, heated side view
mirrors and front wiper de-icer grid. In addition the
front wiper de-ice function is turned on when front
defog/defrost mode is selected.
When the defroster button is pushed, the HVAC
control sends a bus message over the PCI bus to the
Front Control Module (FCM) which controls the
Rear Window Defogger relay. The defroster LED
will illuminate when the defroster function is on.
The defroster will function for 10 minutes or can be
cycled off sooner by pressing the defroster button
again. The front wiper de-icer grid receives its 12
volts from the accessory relay through fuse 11 and
the HVAC control module supplies the grid ground.
3.20 VEHICLE THEFT SECURITY SYSTEM
3.20.1 BASE ALARM SYSTEM
The Vehicle Theft Security System (VTSS) is part
of the Body Control Module (BCM). The BCM
monitors the vehicle doors, liftgate, hood, and theignition for unauthorized operation. The alarm ac-
tivates by sounding the horn, flashing the head-
lamps and the VTSS indicator lamp. The VTSS does
not prevent engine operation, this is done with the
Sentry Key Immobilizer Module (SKIM). Passive
arming occurs in one of two ways. Upon normal
vehicle exit by removing the ignition key, opening
the driver door, locking the doors with the power
lock, and closing the driver door, or by removing the
ignition key, opening the driver door, closing the
driver door, and locking the doors with the Remote
Keyless Entry (RKE) transmitter. The VTSS indi-
cator lamp will flash for approximately 15 seconds
during the arming process. If there is no interrup-
tion during the arming process, upon completion
the VTSS indicator lamp will flash at a slower rate.
When the BCM receives an input to trigger the
alarm, the BCM will control the outputs of the
headlamps, horn, and VTSS lamp for approxi-
mately 18 minutes.
Arming (Active and Passive)
Active arming occurs when the RKE transmitter
is used to lock the vehicle doors, whether the doors
are open or closed. The arming process is complete
only after all doors are closed.
Passive arming occurs when the ignition key is
removed, the driver door is opened, and the doors
are locked with the power door lock switch, and the
door is closed.
Disarming (Active and Passive)
Active disarming occurs when the RKE transmit-
ter is used to unlock the vehicle doors. This disarm-
ing will also halt the alarm once it has been acti-
vated.
Passive disarming occurs upon normal vehicle
entry (unlocking driver door with the key). This
disarming will also halt the alarm once it has been
activated.
Tamper Alert
The VTSS tamper alert will sound the horn three
times upon disarming to indicate a tamper condi-
tion has occurred.
Manual Override
The system will not arm if the doors are locked
using the manual lock control or if the locks are
actuated by an inside occupant after the doors are
closed.
Diagnosis
For complaints about the Vehicle Theft Alarm
triggering on its own, use the DRBIIItand read the
Last VTSS Cause status.
26
GENERAL INFORMATION

WARNING: BEFORE ROAD TESTING A
VEHICLE, BE SURE THAT ALL
COMPONENTS ARE REASSEMBLED.
DURING THE TEST DRIVE, DO NOT TRY TO
READ THE DRBIIITSCREEN WHILE IN
MOTION. DO NOT HANG THE DRBIIITFROM
THE REAR VIEW MIRROR OR OPERATE IT
YOURSELF. HAVE AN ASSISTANT
AVAILABLE TO OPERATE THE DRBIIIT.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box)
Jumper wires
Ohmmeter
Voltmeter
Sentry Key Tester
Test Light
8310 Airbag System Load Tool
8443 SRS Airbag System Load Tool
Diagnostic Junction Port Tester 8339
6.0 GLOSSARY OF TERMS
ABSantilock brake system
ACMairbag control module
AECMairbag electronic control module
(ACM)
ASDMairbag system diagnostic module
(ACM)
AT Cautomatic temperature control
BCMbody control module
CABcontroller antilock brake
CMTCcompass/mini-trip computer
CPAconnector positive assurance
DABdriver airbag
DCHAdiesel cabin heater assist
(cabin heater)
DLCdata link connector
DTCdiagnostic trouble code
DRdriver
EBLelectric back lite (rear window de-
fogger)ECMEngine control module
EVICelectronic vehicle information center
FCMfront control module
GCCGulf Coast Countries
HVACheater ventilation, air conditioning
IPMintelligent power module
LDUlower drive unit
LHDLeft Hand Drive
MICmechanical instrument cluster
MTCmanual temperature control
MSMMmemory seat/mirror module
OBDon board diagnostics
ODOodometer
ORCoccupant restraint controller
PA Bpassenger airbag
PASSpassenger
PCIProgrammable Communication In-
terface (vehicle communication bus)
PCMpowertrain control module
PDCpower distribution center
PLGpower liftgate
PLGMpower liftgate module
PSDpower sliding door
PSDMpower sliding door module
PWMpulse width modulated
RHDRight Hand Drive
RKEremote keyless entry
SABseat airbag
SBTseat belt tensioner
SIACMside impact airbag control module
SKIMsentry key immobilizer module
SKISsentry key immobilizer system
SQUIBalso called initiator (located inside
airbag)
SRSsupplemental restraint system
TCMtransmission control module
VFDvacuum fluorescent display
VTSSvehicle theft security system
30
GENERAL INFORMATION

Symptom:
*BUS +/- SIGNALS OPEN FROM MEMORY SEAT/MIRROR MODULE
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE BCM
FUSED SEAT SWITCH DRIVER CIRCUIT OPEN
GROUND CIRCUIT OPEN
OPEN PCI BUS CIRCUIT
MEMORY SEAT/MIRROR MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, enter Body then Body Computer.
Was the DRB able to I/D or communicate with the BCM?All
Ye s®Go To 2
No®Refer to the symptom list for problems related to no communica-
tion with the BCM.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Memory Seat/Mirror Module C4 harness connector.
Using a 12-volt test light connected to ground, probe the Fused Seat Switch Driver
circuit.
Is the test light illuminated?All
Ye s®Go To 3
No®Check the Power Seat Circuit Breaker for an open or short. If ok,
repair the Fused Seat Switch Driver circuit for an open or short.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Disconnect the Memory Seat/Mirror Module C4 harness connector.
Measure the resistance between ground and the ground circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 4
No®Repair the ground circuit for an open.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
375
COMMUNICATION

TEST ACTION APPLICABILITY
4Note: Ensure there is PCI Bus communication with other modules on the
vehicle before proceeding. If not, refer to the symptom list from the menu
and repair as necessary.
Turn the ignition off.
Disconnect the Memory Seat/Mirror Module C2 harness connector.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
With the DRBIIItselect Pep Module Tools.
Select lab scope.
Select Live Data.
Select 12 volt square wave.
Press F2 for Scope.
Press F2 and use the down arrow to set voltage range to 20 volts. Press F2 again
when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the Memory Seat/Mirror Module connector.
Turn the ignition on.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?All
Ye s®Go To 5
No®Repair the PCI Bus circuit for an open.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
5 If there are no possible causes remaining, view repair. All
Repair
Replace the Memory Seat/Mirror Module.
Perform MEMORY SYSTEM VERIFICATION TEST - VER 1.
376
COMMUNICATION
*BUS +/- SIGNALS OPEN FROM MEMORY SEAT/MIRROR MODULE Ð
Continued

Symptom:
HEADLAMP SWITCH MISMATCH
When Monitored and Set Condition:
HEADLAMP SWITCH MISMATCH
When Monitored: Ignition ON
Set Condition: Headlamp switch is in Auto mode and the vehicle is not EC Mirror
equipped.
POSSIBLE CAUSES
VERIFY AUTO HEADLAMP SWITCH
INTERMITTENT WIRING AND CONNECTORS
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, record and erase DTC's.
Turn the headlamps to the Auto position.
With the DRBIIIt, read DTCs.
Does the DRBIIItdisplay HEADLAMP SWITCH MISMATCH?All
Ye s®Go To 2
No®Go To 4
2 Visually identify the Headlamp Switch type.
Does the Headlamp Switch Contain an Auto Headlamp position?All
Ye s®Replace the Auto Headlamp Switch with a non Auto Headlamp
Switch.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
3 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Body Control Module in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
4 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wiring while checking for shorts and open circuits.
Were there any problems found?All
Ye s®Repair as necessary.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
449
EXTERIOR LIGHTING

Symptom:
PANEL DIMMING OUTPUT SHORT
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
EMIC DIMMING CIRCUIT SHORT TO GROUND
HEADLAMP SWITCH DIMMING CIRCUIT SHORT TO GROUND
HVAC MODULE DIMMING CIRCUIT SHORT TO GROUND
I/P MULTI-FUNCTION SWITCH DIMMING CIRCUIT SHORT TO GROUND
MIRROR SWITCH DIMMING CIRCUIT SHORT TO GROUND
RADIO DIMMING CIRCUIT SHORT TO GROUND
REAR BLOWER CONTROL SWITCH DIMMING CIRCUIT SHORT TO GROUND
EMIC
HEADLAMP SWITCH
I/P MULTI-FUNCTION SWITCH
MIRROR SWITCH
RADIO
REAR BLOWER CONTROL SWITCH
BODY CONTROL MODULE
HVAC MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, record and erase Body Control Module DTC's.
Turn the ignition off, wait 15 seconds, then turn the ignition on.
Turn on the Headlamps.
With the DRBIIIt, read DTCs.
Does the DRBIIItdisplay PANEL DIMMING OUTPUT SHORT?All
Ye s®Go To 2
No®Go To 17
2 Turn the ignition on.
With the DRBIIIt, erase Body Control Module DTCs.
Turn the ignition off to the lock position.
Disconnect the EMIC harness connector.
Turn the ignition on.
Turn the Headlamps on.
With the DRBIIIt, read DTCs.
Does the DRBIIItdisplay PANEL DIMMING OUTPUT SHORT?All
Ye s®Go To 3
No®Replace the EMIC in accordance with the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
595
INSTRUMENT CLUSTER