One Trailer Brake Assembly Heats Up But Stops When Brakes Are Disconnected

Question:

Have a hot hub 120c and the other three seem okay. Have disconnected electric brakes which fixes the problem. What’s wrong???

asked by: Dale

Expert Reply:

From what you describe, it sounds as if you might have a combination of two separate issues happening.

I suspect that you have one trailer brake assembly that's adjusted a bit further out than the others, combined with either a faulty brake controller that's putting out voltage when it shouldn't or corrosion that has built up in the trailer connector allowing power from a different circuit such as the 12-v supply to the trailer to bridge to the brake circuit. An out of adjustment brake assembly would rub constantly, which would make it hot all the time and wouldn't go away when the trailer brakes are disconnected. However, if you add voltage output on the brake circuit that shouldn't be there, the combination of the two could certainly cause the problem you're experiencing.

I'll link to an article that explains how to adjust trailer brakes as well a brake controller troubleshooting article. If you could reply with the brand and model of brake controller you're using as well as the year, make and model of vehicle I can dig further.

expert reply by: Mike L