
Symptom:
SKIM MESSAGES NOT RECEIVED
When Monitored and Set Condition:
SKIM MESSAGES NOT RECEIVED
When Monitored: With the ignition in run, and the IOD fuse installed.
Set Condition: The BCM does not receive any messages from the Sentry Key Immobilizer
Module (SKIM) for at least 5 seconds.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE SENTRY KEY IMMOBILIZER MODULE
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, attempt to communicate with the SKIM.
Was the DRB able to I/D or communicate with the SKIM?All
Ye s®Go To 2
No®Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRB, erase DTC's.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRB, read DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
371
COMMUNICATION

Symptom:
TCM MESSAGES NOT RECEIVED
When Monitored and Set Condition:
TCM MESSAGES NOT RECEIVED
When Monitored: With the ignition in run, and the IOD fuse installed.
Set Condition: The BCM does not receive any messages from the Transmission Control
Module (TCM) for at least 5 seconds.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE TCM
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, attempt to communicate with the Transmission Control Module.
Was the DRB able to I/D or communicate with the TCM?All
Ye s®Go To 2
No®Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRB, erase DTC's.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRB, read DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
372
COMMUNICATION

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Install a known good relay in place of the Rear Window Defogger relay.
Turn the ignition on.
Attempt to operate the Rear Window Defogger.
With the DRBIIIt, read the current Front Control Module DTC's.
Does the DTC reset?All
Ye s®Go To 5
No®Replace the Rear Defogger Relay.
Perform BODY VERIFICATION TEST - VER 1.
5 Turn the ignition off.
Disconnect the Front Control Module from the Fuse and Relay Center.
Remove the Rear Window Defogger Relay.
Measure the resistance of the Rear Window Defogger Relay Control Circuit in the
Fuse and Relay Center.
Is the resistance below 5.0 ohms?All
Ye s®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Fuse and Relay Center.
Perform BODY VERIFICATION TEST - VER 1.
441
ELECTRICALLY HEATED SYSTEMS
EBL RUN ONLY RELAY OPEN ÐContinued

Symptom:
EBL RUN ONLY RELAY SHORTED TO BATTERY
When Monitored and Set Condition:
EBL RUN ONLY RELAY SHORTED TO BATTERY
When Monitored: Continuously with the ignition on.
Set Condition: The FCM has detected a short to battery voltage in the Rear Defogger
Relay control circuit.
POSSIBLE CAUSES
VERIFY ACTIVE DTC
FRONT CONTROL MODULE
INTELLIGENT POWER MODULE
REAR WINDOW DEFOGGER RELAY
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, erase the current Front Control Module DTC's.
Turn the ignition off, wait 10 seconds then turn the ignition on.
With the DRBIIIt, read the current Front Control Module DTC's.
Does the DRBIIItdisplay EBL RUN ONLY RELAY SHORTED TO BATTERY
trouble code?All
Ye s®Go To 2
No®The condition that caused this symptom is currently not present
at this time.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Install a known good relay in place of the Rear Window Defogger relay.
Turn the ignition on.
Attempt to operate the Rear Window Defogger.
With the DRBIIIt, read the current Front Control Module DTCs.
Did the DTC reset?All
Ye s®Go To 3
No®Replace the Rear Defogger Relay.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Remove the Rear Window Defogger Relay from the IPM.
Remove the Front Control Module from the IPM.
Measure the voltage of the Rear Window Relay Control circuit.
Is the voltage above 1.0 volts?All
Ye s®Replace the Fuse and Relay Center.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
442
ELECTRICALLY HEATED SYSTEMS

ZONE OVERCURRENT (ACTIVE) - MANUAL A/C
When Monitored: When actuator movement is requested.
Set Condition: All (Blend, Mode, Recirc, and Zone) Overcurrent DTCs will set if the A/C
- Heater Control Module detects an excessive current draw on the Common Door Drive
circuit(s).
POSSIBLE CAUSES
MODE DOOR ACTUATOR SHORTED
RECIRCULATION DOOR ACTUATOR SHORTED
PASSENGER BLEND DOOR ACTUATOR SHORTED
DRIVER BLEND DOOR ACTUATOR SHORTED
DOOR DRIVER CIRCUIT SHORTED TO GROUND
DOOR DRIVER CIRCUITS SHORTED TOGETHER
A/C - HEATER CONTROL MODULE
REAR BLEND DOOR ACTUATOR SHORTED
REAR MODE DOOR ACTUATOR SHORTED
REAR A/C HEATER UNIT WIRING HARNESS SHORTED
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Mode Door Actuator harness connector.
Turn the ignition on.
With the DRB, erase the HVAC DTCs.
Cycle the ignition switch from off to on and monitor the HVAC DTCs. Note: make
sure the active DTCs are erased at this time.
Slowly turn the mode door knob through each of it's different positions. Perform this
step a few times.
Turn the mode door knob to the Panel, Bi-level, or Floor position.
Press and release the recirculation button. Perform this step a few times.
Slowly slide the front temperature control levers (if equipped with dual or three zone,
slide all front levers) from hot to cold and back to hot. Perform this step a few times.
Slowly turn the rear blend/mode door knob from hot to cold and back to hot (if
equipped with rear A/C). Perform this step a few times.
With the DRB, read the active HVAC DTCs.
Did the overcurrent DTCs reset?All
Ye s®Go To 2
No®Replace the Mode Door Actuator in accordance with the Service
Information.
Perform BODY VERIFICATION TEST - VER 1.
527
HEATING & A/C
BLEND OVERCURRENT (ACTIVE) - MANUAL A/C ÐContinued

TEST ACTION APPLICABILITY
2 Turn the ignition off.
Disconnect the Recirculation Door Actuator harness connector.
Turn the ignition on.
With the DRB, erase the HVAC DTCs.
Cycle the ignition switch from off to on and monitor the HVAC DTCs. Note: make
sure the active DTCs are erased at this time..
Slowly turn the mode door knob through each of it's different positions. Perform this
step a few times.
Turn the mode door knob to the Panel, Bi-level, or Floor position.
Press and release the recirculation button. Perform this step a few times.
Slowly slide the front temperature control levers (if equipped with dual or three zone,
slide all front levers) from hot to cold and back to hot. Perform this step a few times.
Slowly turn the rear blend/mode door knob from hot to cold and back to hot (if
equipped with rear A/C). Perform this step a few times.
With the DRB, read the active HVAC DTCs.
Did the overcurrent DTCs reset?All
Ye s®Go To 3
No®Replace the Recirculation Door Actuator in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Disconnect the Passenger Blend Door Actuator harness connector.
Turn the ignition on.
With the DRB, erase the HVAC DTCs.
Cycle the ignition switch from off to on and monitor the HVAC DTCs. Note: make
sure the active DTCs are erased at this time..
Slowly turn the mode door knob through each of it's different positions. Perform this
step a few times.
Turn the mode door knob to the Panel, Bi-level, or Floor position.
Press and release the recirculation button. Perform this step a few times.
Slowly slide the front temperature control levers (if equipped with dual or three zone,
slide all front levers) from hot to cold and back to hot. Perform this step a few times.
Slowly turn the rear blend/mode door knob from hot to cold and back to hot (if
equipped with rear A/C). Perform this step a few times.
With the DRB, read the active HVAC DTCs.
Did the overcurrent DTCs reset?All
Ye s®Go To 4
No®Replace the Passenger Blend Door Actuator in accordance with
the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
528
HEATING & A/C
BLEND OVERCURRENT (ACTIVE) - MANUAL A/C ÐContinued

TEST ACTION APPLICABILITY
4NOTE: If vehicle is equipped with a base HVAC system, answer yes to the
question.
Turn the ignition off.
Disconnect the Driver (zone) Blend Door Actuator harness connector.
Turn the ignition on.
With the DRB, erase the HVAC DTCs.
Cycle the ignition switch from off to on and monitor the HVAC DTCs. Note: make
sure the active DTCs are erased at this time..
Slowly turn the mode door knob through each of it's different positions. Perform this
step a few times.
Turn the mode door knob to the Panel, Bi-level, or Floor position.
Press and release the recirculation button. Perform this step a few times.
Slowly slide the front temperature control levers (if equipped with dual or three zone,
slide all front levers) from hot to cold and back to hot. Perform this step a few times.
Slowly turn the rear blend/mode door knob from hot to cold and back to hot (if
equipped with rear A/C). Perform this step a few times.
With the DRB, read the active HVAC DTCs.
Did the overcurrent DTCs reset?All
Ye s®Go To 5
No®Replace the Driver Blend Door Actuator in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
5NOTE: If vehicle is equipped with a base HVAC or dual zone system, answer
yes to the question.
Turn the ignition off.
Disconnect the Rear A/C Heater Unit harness connector.
Turn the ignition on.
With the DRB, erase the HVAC DTCs.
Cycle the ignition switch from off to on and monitor the HVAC DTCs. Note: make
sure the active DTCs are erased at this time..
Slowly turn the mode door knob through each of it's different positions. Perform this
step a few times.
Turn the mode door knob to the Panel, Bi-level, or Floor position.
Press and release the recirculation button. Perform this step a few times.
Slowly slide the front temperature control levers (if equipped with dual or three zone,
slide all front levers) from hot to cold and back to hot. Perform this step a few times.
Slowly turn the rear blend/mode door knob from hot to cold and back to hot. Perform
this step a few times.
With the DRB, read the active HVAC DTCs.
Did the overcurrent DTCs reset?All
Ye s®Go To 6
No®Go To 8
6 Turn the ignition off.
Disconnect each door actuator harness connector (front actuators only).
Disconnect the A/C - Heater Control Module C1 harness connector.
Disconnect the Rear A/C Heater Unit harness connector (if equipped with rear A/C).
Measure the resistance between ground and each HVAC door driver circuit.
Is the resistance below 10K ohms for any of the measurements?All
Ye s®Repair all door driver circuits with a resistance below 10K ohms
for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 7
529
HEATING & A/C
BLEND OVERCURRENT (ACTIVE) - MANUAL A/C ÐContinued

TEST ACTION APPLICABILITY
7 Turn the ignition off.
Disconnect each door actuator harness connector (front actuators only).
Disconnect the A/C - Heater Control Module C1 harness connector.
Disconnect the Rear A/C Heater Unit harness connector (if equipped with rear A/C).
Measure the resistance between the Common Door Driver circuit and each other door
driver circuit.
Measure the resistance between the Recirculation Door Driver circuit and each other
door driver circuit.
Measure the resistance between the Mode Door Driver circuit and each other door
driver circuit.
Measure the resistance between the Passenger Blend Air Door Driver circuit and
each other door driver circuit.
Measure the resistance between the Driver Blend Door Driver circuit and each other
door driver circuit (if equipped with dual or 3 zone).
Measure the resistance between the Rear Common Door Driver circuit and each
other door driver circuit (if equipped with rear A/C).
Measure the resistance between the Rear Blend Door Driver circuit and each other
door driver circuit (if equipped with rear A/C).
Measure the resistance between the Rear Mode Door Driver circuit and each other
door driver circuit (if equipped with rear A/C).
Is the resistance below 10K ohms for any of the measurements?All
Ye s®Repair the door driver circuits that measured below 10K ohms for
a short to each other.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the A/C - Heater Control Module in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
8 Turn the ignition off.
Reconnect the Rear A/C Heater Unit harness connector.
Disconnect the Rear Blend Door Actuator harness connector.
Turn the ignition on.
With the DRB, erase the HVAC DTCs.
Cycle the ignition switch from off to on and monitor the HVAC DTCs. Note: make
sure the active DTCs are erased at this time.
Slowly turn the mode door knob through each of it's different positions. Perform this
step a few times.
Turn the mode door knob to the Panel, Bi-level, or Floor position.
Press and release the recirculation button. Perform this step a few times.
Slowly slide the front temperature control levers (if equipped with dual or three zone,
slide all front levers) from hot to cold and back to hot. Perform this step a few times.
Slowly turn the rear blend/mode door knob from hot to cold and back to hot. Perform
this step a few times.
With the DRB, read the active HVAC DTCs.
Did the overcurrent DTCs reset?All
Ye s®Go To 9
No®Replace the Rear Blend Door Actuator in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
530
HEATING & A/C
BLEND OVERCURRENT (ACTIVE) - MANUAL A/C ÐContinued