Troubleshooting Trailer Brakes Blowing Fuse When Truck Brakes Are Applied

Updated 05/09/2017 | Published 05/07/2017

Products Featured in This Question

Hook Probe Circuit Tester

(60)

$12.88

10 Gauge Wire - Blue Primary - Per Foot

(104)

$1.84

Question:

I have an enclosed car hauler and starting this year it has been blowing the in-line fuse in the brake controller on my truck. The trailer has 4 wheel brakes and Ive been usjng the same truck for several years without a problem until now. Ive used the same truck with a buddies trailer and had no issues. How would I go about testing to see which of the trailer wheels is having the braking issue causing the short?

asked by: John

Expert Reply:

Since you know there is a short in the braking system itself, I recommend starting with testing your trailer magnets. I've attached an article to help you with this.

If the magnets check out then you know you have a short in the wiring. I recommend testing the wires with an incandescent circuit tester like # PTW2993 and probing the wire until you find the issue. Replace wire as needed with # 10-1-1.

expert reply by: Jason S