Troubleshooting Check Trailer Wiring Message on 2013 GMC Sierra 1500

Updated 08/28/2023 | Published 08/27/2023

Question:

I have a 2013 Sierra 1500 and am getting the check trailer wiring message. I have no voltage to the electric trailer brake pin on the 7 pin plug when the brakes are depressed. Not sure if it is the relay or controller module. Wiring looks good. Im considering a RED44FR. If I plug this one in will the error message I get on my dash stop coming up?

asked by: Robert M

Expert Reply:

Your 2013 GMC Sierra trailer wiring message should have more to do with a ground or one of the light functions on your trailer plug so you'll want to make sure all of the lights on the trailer are operational and the grounds are secured to a clean, bare-metal surface. If all of that looks good then you need to check the wiring connections inside your truck and trailer 7-Way plug and socket.

If your brake controller was the issue then I'm pretty positive there would be a "brake controller error" message instead of just the trailer wiring. I know you tested the brake output using the brake pedal but the inertia sensor would have been reading that the truck wasn't moving which is likely why you are seeing power (try using the manual override and checking for power again). Nevertheless, if you still want to swap out your brake controller then the Redarc Tow-Pro Elite # RED44FR that you referenced is an excellent option!

I've attached a helpful article we made for people with your truck and trailer situation for you to reference.

expert reply by: Jon G