* The trailer brake control module clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.
Reference Information
Schematic Reference
Trailer Brake Control Schematics (See: Brakes and Traction Control/Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Trailer Brake Controls Description and Operation (See: Powertrain Management/Computers and Control Systems/Description and
Operation/Trailer Brake Controls 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
Circuit/System Verification
Ignition ON, observe the scan tool trailer brake controls user gain parameter. The reading should be between 0-100 percent, and change with
operating the gain switch up or gain switch down.
Circuit/System Testing
Note: These diagnostics are based on having no trailer connected.
1. Ignition ON, verify that DTC P2534 is not set.
锟斤拷If the DTC is set, refer to DTC P2534 (See: P Code Charts/P2534/Wiring Systems and Power Management).
2. Ignition OFF, disconnect the harness connector at the solid state relay.
3. Test for less than 5 ohm between the ground circuit terminal B and ground.
锟斤拷If greater than the specified range, test the ground circuit for an open/high resistance.
4. Ignition OFF, verify that a test lamp illuminates between the B+ circuit terminal F and ground.
锟斤拷If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the
STUD 2 fuse is open, replace the trailer brake control relay.
5. Ignition ON, verify that a test lamp does not illuminate between control circuit terminal E and ground.
锟斤拷If test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the trailer brake control module.
6. Ignition ON, verify that a test lamp does not illuminate between control circuit terminal E and B+.
锟斤拷If test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the trailer brake control module.
7. Ignition ON, test for 3.2-4.1 V between the control circuit terminal C and ground.
锟斤拷If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace
the trailer brake control module.
锟斤拷If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the trailer brake control
module.
8. Ignition ON, test for 3.2-4.1 V between the control circuit terminal A and ground.
锟斤拷If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace
the trailer brake control module.
