Troubleshooting Trailer Brakes on Horse Trailer

Published 06/03/2021

Question:

I have a 2012 Adam horse trailer that when hooked to a 2016 Chevy 2500 the dash reads trailer disconnected/check trailer wiring. All the lights and brake lights work but the brakes do not. When hooked up to a trailer tester and an older truck with a manual brake controller the brakes work fine. Weve fixed all the grounds and power wires to the brakes but still cant get them to work correctly. Trailer also has a brand new plug.

asked by: Vernon F

Expert Reply:

I'm unsure what you mean by a 'manual' brake controller. Could you perhaps mean that your truck has the factory brake controller built into the dash?

If that's the case, some factory brake controllers have proven to be problematic. Some have been so problematic that Tekonsha came out with a tech bulletin showing folks how to bypass the OE brake controller and install and aftermarket unit, which I'll link you to.

In my experience, some vehicles with the OE brake controllers are just more picky about the trailers they'll work with. It's possible that the trailer's brake magnets are worn which the OE controller picks up on but an aftermarket one didn't.

I'd begin by checking the brake magnets. If you can see any copper wire showing through the front face of the magnet that rides against the inside of the brake drum, then the magnets are worn and need to be replaced. They could very well be causing the problem you're experiencing.

If you don't have the factory controller in your Silverado, please let me know which brake controller you're using and I'd be glad to look into it further.

expert reply by: Mike L