Inspection and Verification

WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

Verify the customer concern.

Visually inspect for obvious signs of mechanical or electrical damage.

VISUAL INSPECTION CHART

Mechanical	Electrical
Base brake system Trailer	Battery Junction Box (BJB) fuse 22 (30A) Body Control Module (BCM) fuse 35 (5A) Wiring, terminals or connectors Trailer Brake Control (TBC) module

If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
NOTE: Make sure to use the latest scan tool software release.

If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
NOTE: The Vehicle Communication Module (VCM) LED prove out confirms power and ground from the DLC are provided to the VCM.

If the scan tool does not communicate with the VCM:
- check the VCM connection to the vehicle.
- check the scan tool connection to the VCM.
- refer to MODULE COMMUNICATIONS NETWORK , No Power To The Scan Tool, to diagnose no power to the scan tool.
If the scan tool does not communicate with the vehicle:
- verify the ignition key is in the ON position.
- verify the scan tool operation with a known good vehicle.
- refer to MODULE COMMUNICATIONS NETWORK to diagnose no response from the PCM.
Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to MODULE COMMUNICATIONS NETWORK .
- If the network test passes, retrieve and record the continuous memory DTCs.
Clear the continuous DTCs and carry out the self-test diagnostics for the TBC module.
If the DTCs retrieved are related to the concern, go to the Trailer Brake Control (TBC) Module DTC Chart .
If no DTCs related to the concern are retrieved, GO to SYMPTOM CHART .