Conditions for Setting the DTC
The rear fog lamp switch signal circuit is active for longer than 10 minutes.
Action Taken When the DTC Sets
The rear fog lamps will be disabled.
Conditions for Clearing the DTC
* The DTC will be current for as long as the fault is present.
* When the fault is no longer present, the DTC will be a history status code.
* A history DTC will clear after 50 ignition cycles or with a scan tool using the clear DTCs function.
Reference Information
Schematic Reference
Fog Lights Schematics (See: Diagrams/Electrical Diagrams/Lighting and Horns/System Diagram/Fog Lights Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems Description
and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
System Verification
Ignition ON, observe the scan tool Rear Fog Lamp Switch parameter while turning the rear fog lamp switch ON and OFF. The parameter should
change between Active and Inactive.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the headlamp and panel dimmer switch.
2. Ignition OFF, verify a test lamp illuminates between B+ and the ground circuit terminal 8.
锟斤拷 If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
3. Verify the scan tool Rear Fog Lamp Switch parameter displays Inactive.
锟斤拷 If not the specified value, test the signal circuit terminal 6 for a short to ground. If the circuit tests normal, replace the XBCM.
4. Install a 3 A fused jumper wire between the signal circuit terminal 6 and the ground circuit terminal 8. Verify the scan tool Rear Fog Lamp
Switch parameter is Active.
锟斤拷 If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the
XBCM.
5. If all circuits test normal, replace the headlamp and panel dimmer switch.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Headlamp Switch Replacement (Cadillac) (See: Lighting and Horns/Headlamp/Headlamp Switch/Service and Repair/Headlamp Switch
