Weak Trailer Brakes With No Change After Rewiring Trailer

Published 12/17/2019

Question:

I have a trailer that has weak brakes. I have rewired the whole trailer with 7 wire loom and a new connector, that didnt work. We put new magnets on and that didnt fix it so I ordered new complete brake assemblies and turned the drums. I also used a sanding disc and cleaned the surface where the magnet attaches. They still are weak. With the gain turned all the way up on the truck, 2013 Chevy 2500, it still will not keep the truck from moving forward when you take your foot off the pedal but still have the controller all the way on. What would you suggest I try next?

asked by: D M

Expert Reply:

If you are having issues with weak trailer brakes you will first need to start at the tow vehicle and test the trailer connector for voltage on the brake output wire. In order to do this properly you will need to turn the brake controller all the way up and apply the manual override. If you don't get a full 12 volts then you know the issue is on the vehicle. If the issues is on the vehicle then test the brake output wire directly behind the controller once severed. If you don't get 12 volts then replace the brake controller but if you do get 12 volts then there is a wiring issues.

If you get 12 volts at the trailer connector under the above conditions then the issue is on the trailer side. I recommend checking the grounds for the brake magnets as that could cause weak braking. Also, be sure you have the braking assemblies installed on the proper sides and they are adjusted.

expert reply by: Conner L