Trailer Brake Controller Does Not See that a Trailer Is Connected

Question:

2015 Chrysler TnC pulling Rockwood 2280BHESP. The controller does not display c when trailer is connected. All it shows is 2 red dots. I have verified the wiring from the battery and controller to the socket on the vehicle. What do I check next?

asked by: Greg R

Expert Reply:

A brake controller is looking for the draw from brake magnets on the trailer. If the trailer is connected and it does not indicate that a trailer is connected then the brake controller is not sensing any power draw from the brake magnets.

A few things could cause this issue. First, it could be a wiring problem. You mentioned that you checked the wiring on the vehicle and that it was good so that would seem to indicate that the issue is on the trailer side.

Make sure that the trailer, and vehicle side while you're at it, connectors are clean and free of corrosion inside, where the wires attach, and outside. Trace the wiring from the trailer connector to the brake magnets and fix any broken or pinched wires. Make sure the brake magnets are grounded to a clean, bare metal surface near-ish the magnets.

If the trailer has a breakaway system make sure that it is in good working order along with its wiring. I have included some additional links on testing and troubleshooting brake controllers along with testing brake magnets should you need to.

expert reply by: Michael H