2010 Cadillac Truck SRX AWD V6-3.0L Page 731
Action Taken When the DTC Sets
The trailer backup lamps will be inoperative.
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 DTC.
* A history DTC will clear after 40 ignition cycles.
Reference Information
Schematic Reference
Trailer Connector/Provision Schematics (See: Diagrams/Electrical Diagrams/Starting and Charging/Power and Ground Distribution/System
Diagram/Trailer Connector/Provision Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Description and Operation
Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems)
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
Circuit/System Verification
Ignition ON, observe the function of the trailer backup lamps while commanding the Trailer Backup Lamp ON and OFF with a scan tool. The
trailer backup lamps should turn ON and OFF while changing between the commanded states.
Circuit/System Testing
1. Ignition OFF, disconnect the X1 harness connector at the K68 trailer lighting control module.
2. Test for infinite resistance between the control circuit terminal 7 and ground.
瀚慖f less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
3. Test for less than 1 ohm between the control circuit terminal 7 at the K68 trailer lighting control module and control circuit terminal 8 at the
X88 trailer connector.
瀚慖f greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal,
replace the X88 trailer connector.
4. If all the circuits test normal, replace the K68 trailer lighting control module.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for the trailer brake control module replacement, setup
and programming
B3902
DTC B3902
Diagnostic Instructions
