Troubleshooting A Truck That Is Giving a Check Trailer Wiring Error

Updated 09/25/2023 | Published 09/24/2023

Question:

I have a 2015 Grand design fifth wheel, when towing, the truck continues to say “check trailer brake wiring”. Then the brakes will disconnect and reconnect constantly through out the drive. I tested the truck and everything seems to be working properly there, I ran new power wires from the connector back to the brakes and also have run new wires from the driver side over to the passenger side of the trailer. I checked the wires on the magnets and don’t see a break in them, is it possible for the magnets to be going bad? Any other ideas? Thank you

asked by: Shaun

Helpful Expert Reply:

There also is a pretty high probability that you have a bad ground. This should be attached to a clean unpainted surface that is free of rust.

You'll also need to look to see if the connection is broken, loose, or damaged. If you check and it is not damaged and in an acceptable area, then I recommend try and trace your wires to see where the problem is.

I have attached a FAQ that goes into a bit more detail on what you can do, and what to look for when you troubleshoot your 7-way.

expert reply by: Bryce D