Trailer Brake Controller Shows No Connection to Trailer After Blown Tire

Question:

My trailer brakes were working fine until in had a blown trailer tire. Since then they are showing that there its no connection on the brake controller. The trailer lights are all working and the trailer battery will charge when connected. I also changed the fuse on the wiring connecting to the trailer battery. Everything looks gone on a quick visual check, but I am not sure about what our where to check on the trailer itself out how to check wiring throughout the system. Thanks

asked by: Spencer Z

Expert Reply:

I think I know what might have happened. When the tire let loose, it must have damaged the brake output circuit on your trailer. Each brake magnet has two leads, one that connects to the brake output circuit that leads to the trailer connector and ultimately to the brake controller. The other lead grounds to the trailer frame. If any of these wires has been severed, it'd cause the problem you describe.

Start at the trailer connector, and trace the brake output circuit rearward to the brake magnets. Look for severed wires or loose connections. Repair as needed.

I've linked you to our FAQ articles about trailer wiring, I hope you'll find them helpful.

expert reply by: Mike L