2010 Cadillac Truck SRX AWD V6-3.0L Page 387
Circuit/System Description
The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an
analog voltage signal to the body control module (BCM). The BCM will apply battery voltage to the right, left and center stop lamp control circuits
and to the trailer brake control module if equipped.
Conditions for Running the DTC
When the brake pedal is applied.
Conditions for Setting the DTC
The trailer brake control module receives a serial data message from the BCM that the brakes have been applied, but the trailer brake control
module does not detect a signal voltage on the center high mounted stop lamp control circuit.
Action Taken When the DTC Sets
The brake lights on the trailer 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 50 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
Observe the function of the E6 center high mounted stop lamp while pressing and releasing the brake pedal. The E6 center high mounted stop lamp
should turn ON when the pedal is pressed and OFF when the pedal is released.
If the E6 center high mounted stop lamp is always ON or always OFF, refer to Stop Lamps Malfunction (See: Lighting and Horns/Testing and
Inspection/Symptom Related Diagnostic Procedures/Stop Lamps Malfunction)
If the E6 center high mounted stop lamp turns ON and OFF as commanded, perform the Circuit/System Testing.
Circuit/System Testing
1. Ignition OFF, disconnect the X1 harness connector at the K67 trailer brake control module.
2. Connect a test lamp between the signal circuit terminal 14 and ground.
3. Ignition ON, command the Center Brake Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF while changing
