Troubleshooting OL Code on Brake Controller

Question:

My brake controller is giving an OL code which I’ve read could mean a short on the ground wire. Would this wire be on the controller side installed on the tow vehicle or a short on the trailer? Needing a clue as to what to look for to fix it.

asked by: Bobby D

Expert Reply:

I'm not sure which brake controller you have but this is typically an overload error. This means there is a short in the trailer brake output circuit. Unplug the trailer and see if the code goes away. If you still have the error check the blue brake output wire on your vehicle for a short. You could also replace it with # 10-1-1.

If unplugging the trailer gets rid of the error code you need to check the trailer wiring. This would be the same brake output wire or possibly a bad ground connection on your trailer magnets. I would check both and repair as needed.

expert reply by: Robin H