Page 657 of 4284
TEST ACTION APPLICABILITY
3 Turn the ignition off.
Gain access to the bottom of the Fuse and Relay Center.
Disconnect connector C9 from the Fuse and Relay Center.
Measure the resistance of the Fused Ignition Switch Output circuit between the FCM
connector cavity 37 and the Fuse and Relay Center connector C9 cavity 2.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Fused Ignition Switch Output circuit for an open
between the Fuse and Relay Center and the ignition switch.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Fuse and Relay Center.
Perform BODY VERIFICATION TEST - VER 1.
628
INTELLIGENT POWER MODULE
IGN RUN/START INPUT WIRING ÐContinued
Page 658 of 4284

Symptom:
IGNITION START INPUT WIRING
When Monitored and Set Condition:
IGNITION START INPUT WIRING
When Monitored: With the ignition on and battery voltage greater than 10.4 volts.
Set Condition: The Fused Ignition Switch Output (Start) circuit voltage at the FCM goes
below 0.5 volts.
POSSIBLE CAUSES
TEST FOR CURRENT DTC'S
FRONT CONTROL MODULE INTERNAL MALFUNCTION
FUSE AND RELAY CENTER INTERNAL MALFUNCTION
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
TEST ACTION APPLICABILITY
1 With the DRBIIIt, record and erase the current Front Control Module DTC's.
Cycle the ignition from ON to OFF.
Start the vehicle and observe the DRBIIIt.
With the DRBIIIt, read DTC's.
Does the DRBIIItdisplay: IGNITION START INPUT WIRING?All
Ye s®Go To 2
No®The condition that caused this DTC is currently not present. Use
the wiring diagram/schematic as a guide, and inspect the related
wiring harness for a possible intermittent condition.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Front Control Module from the Fuse and Relay Center.
Measure the voltage of the Fused Ignition Switch Output circuit (cavity 37) at the
Fuse and Relay Center side of the FCM connector.
Turn the ignition on.
Is the voltage above 10.0 volts?All
Ye s®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
629
INTELLIGENT POWER MODULE
Page 659 of 4284
TEST ACTION APPLICABILITY
3 Turn the ignition off.
Gain access to the bottom of the Fuse and Relay Center.
Disconnect connector C9 from the Fuse and Relay Center.
Measure the resistance of the Fused Ignition Switch Output circuit between the FCM
connector cavity 37 and the Fuse and Relay Center connector C9 cavity 2.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Fused Ignition Switch Output circuit for an open
between the Fuse and Relay Center and the ignition switch.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Fuse and Relay Center.
Perform BODY VERIFICATION TEST - VER 1.
630
INTELLIGENT POWER MODULE
IGNITION START INPUT WIRING ÐContinued
Page 660 of 4284
Symptom:
INTERNAL DRIVER FAULT #1
When Monitored and Set Condition:
INTERNAL DRIVER FAULT #1
When Monitored: Continuously with the ignition on.
Set Condition: The Front Control Module has detected an internal malfunction of the
module.
POSSIBLE CAUSES
FRONT CONTROL MODULE INTERNAL MALFUNCTION
INTERMITTENT CONDITION
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: INTERNAL DRIVER FAULT #1?All
Ye s®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®This symptom represents an internal malfunction in the Front
Control Module. The condition that caused this symptom is
currently not present.
Perform BODY VERIFICATION TEST - VER 1.
631
INTELLIGENT POWER MODULE
Page 661 of 4284
Symptom:
INTERNAL DRIVER FAULT #2
When Monitored and Set Condition:
INTERNAL DRIVER FAULT #2
When Monitored: Continuously with the ignition on.
Set Condition: The Front Control Module has detected an internal malfunction of the
module.
POSSIBLE CAUSES
FRONT CONTROL MODULE INTERNAL MALFUNCTION
INTERMITTENT CONDITION
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: INTERNAL DRIVER FAULT #2?All
Ye s®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®This symptom represents an internal malfunction in the Front
Control Module. The condition that caused this symptom is
currently not present.
Perform BODY VERIFICATION TEST - VER 1.
632
INTELLIGENT POWER MODULE
Page 662 of 4284
Symptom:
INTERNAL DRIVER FAULT #3
When Monitored and Set Condition:
INTERNAL DRIVER FAULT #3
When Monitored: Continuously with the ignition on.
Set Condition: The Front Control Module has detected an internal malfunction of the
module.
POSSIBLE CAUSES
FRONT CONTROL MODULE INTERNAL MALFUNCTION
INTERMITTENT CONDITION
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: INTERNAL DRIVER FAULT #3?All
Ye s®Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®This symptom represents an internal malfunction in the Front
Control Module. The condition that caused this symptom is
currently not present.
Perform BODY VERIFICATION TEST - VER 1.
633
INTELLIGENT POWER MODULE
Page 663 of 4284

Symptom:
DOME LAMP OUTPUT SHORT
When Monitored and Set Condition:
DOME LAMP OUTPUT SHORT
When Monitored: Anytime the Body Control Module is active.
Set Condition: When output voltage status is LOW.
POSSIBLE CAUSES
PANEL LAMPS DIMMER SIGNAL CIRCUIT SHORT
HEADLAMP SWITCH MUX RETURN CIRCUIT SHORT TO GROUND
BODY CONTROL MODULE
COURTESY LAMPS DRIVER DOME CIRCUIT SHORT
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, clear all BCM DTC's.
Turn the Dome Lamps on.
With the DRBIIIt, read the DTC information.
Does the DRBIIItread: Dome Lamp Output Short?All
Ye s®Go To 2
No®Repair the Panel Lamps Dimmer Signal Circuit for a short
condition.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Headlamp Switch harness connector.
Disconnect the Body Control Module harness connector.
Measure the resistance of the Headlamp Switch MUX Return Circuit.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Headlamp Switch MUX Return Circuit for a short to
ground.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
3 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Measure the resistance of the Courtesy Lamps Driver - Dome Circuit.
Is the resistance below 5.0 ohms?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Repair the Courtesy Lamps Driver - Dome Circuit for a short
condition.
Perform BODY VERIFICATION TEST - VER 1.
634
INTERIOR LIGHTING
Page 664 of 4284

Symptom:
DOME SWITCH INPUT OPEN
When Monitored and Set Condition:
DOME SWITCH INPUT OPEN
When Monitored: Dome Lamps Off.
Set Condition: When Voltage is below 4.8 volts for 62.5 msec.
POSSIBLE CAUSES
HEADLAMP SWITCH MUX RETURN CIRCUIT OPEN
PANEL LAMPS DIMMER SIGNAL CIRCUIT OPEN
BODY CONTROL MODULE
HEADLAMP SWITCH
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, clear all BCM DTC's.
Turn the Dome Lamps on.
With the DRBIIIt, read the DTC information.
Does the DRBIIItdisplay: Dome Switch Input Open?All
Ye s®Go To 2
No®Repair the Headlamp Switch MUX Return Circuit for an open
condition.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Disconnect the Headlamp Switch harness connector.
Measure the resistance of the Panel Lamps Dimmer Signal Circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 3
No®Repair the Panel Lamps Dimmer Signal Circuit for an open
condition.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Disconnect the Headlamp Switch harness connector.
Disconnect the Body Control Module harness connector.
Measure the voltage of the Headlamp Switch MUX Return Circuit.
Is the voltage below 4.8 volts?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Headlamp Switch.
Perform BODY VERIFICATION TEST - VER 1.
635
INTERIOR LIGHTING