Symptom Chart: Trailer Brake System
WARNING: This page is about a different car, the 2018 Ford F-550 Super Duty, 2018 Ford F-450 Super Duty, 2018 Ford F-350 Super Duty, and 2018 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods .
| Condition | Possible Sources | Actions |
|---|---|---|
| A module does not respond to the diagnostic scan tool | Fuse Wiring, terminals or connectors Communication network concern TBM |
REFER to: Communications Network . |
| The trailer brakes are inoperative | Refer to the Pinpoint Test | GO to Pinpoint Test A |
| The trailer brakes are always engaged | Refer to the Pinpoint Test | GO to Pinpoint Test B |
| The message center displays TRAILER WIRING FAULT | Refer to the Pinpoint Test | GO to Pinpoint Test C |
| The message center intermittently displays TRAILER DISCONNECTED or TRAILER WIRING FAULT while towing a trailer | Refer to the Pinpoint Test | GO to Pinpoint Test C |
| The message center displays TRAILER BRAKE MODULE FAULT | Diagnostic Trouble Codes (DTCs) present in the TBM | RETRIEVE and RECORD the Diagnostic Trouble Codes (DTCs). GO to DTC Chart: Trailer Brake Control Module (TBM) . |
| The message center displays TRAILER BRAKE MODULE FAULT when the vehicle is not equipped with a TBM | Incorrect IPC configuration | CONFIGURE the IPC car configuration parameters. REFER to: Module Programming . |
| No power at 7 way power/charge wire | Fuse Wiring, terminals or connectors Communication network concern TRM |
REFER to: Trailer Lamps . |
| The message center displays TRAILER CONNECTED when no trailer is connected | Refer to the Pinpoint Test | GO to Pinpoint Test D |
| The message center does not display a TRAILER CONNECTED message when a trailer is connected | Refer to the Pinpoint Test | GO to Pinpoint Test D |