Troubleshooting Trailer Brakes Not Working

Updated 12/06/2022 | Published 12/03/2022

Products Featured in This Question

Hook Probe Circuit Tester

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$12.94

10 Gauge Wire - Blue Primary - Per Foot

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$1.65

Question:

I have break lights….signals but no trailer breaks

asked by: Johnathan

Expert Reply:

There could be a number of different issues causing your trailer brakes to not work. I would start by checking the 7-way connection on your vehicle. Make sure there is no debris, corrosion, or damage. From there, use a circuit tester like the # PTW2993 to check for power on the brake output pin. Make sure you are using the manual override on the brake controller, pressing the brakes when not in motion won't work with a proportional controller. This will help you determine if it is on the vehicle side or trailer side.

If it is in the trailer side, start by checking the trailer connector. From there, check the brake output wire for a short running back to the brakes. You can also check the ground connection to make sure it is secure.

If it is on the vehicle side, go ahead and move to the brake controller and test the brake output wire. If you still don't have power then something is wrong with your brake controller. Double check the connections and make sure the wiring isn't damaged. If you have power here then it is likely a short in the wire. You can find it and repair the short, or run new wire with # 10-1-1.

expert reply by: Robin H