Trailer Brakes Locked Up After Sitting

Published 12/27/2018

Products Featured in This Question

Dexter Electric Trailer Brake Assembly - 12" - Right Hand - 6,000 lbs

(194)

$81.58

Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional

(2776)

$158.63

Question:

I went to tow it yesterday and the trailer brakes were engaged I disconnected the trailer from my truck disconnected the marine battery within the trailer and double checked the break-away pin and still no luck , what could be the issue ? It cant be rusted up I just hauled it over 400 miles 3weeks prior to 12/26/18 and it was working just fine thanks in advance.

asked by: Eddie

Expert Reply:

For starters, I am going to assume that you have electric drum brakes. The issue you described of the brakes locking up could be caused by several different things. In order to save yourself some time, I recommend hooking up the trailer to a different tow vehicle or the tow vehicle to a different trailer. This will then allow you to pinpoint which side the issue is occuring on.

When you said that you disconnected the trailer from the tow vehicle did you check to see if the brakes released? If so then the issue is on the tow vehicle and you either have a short in the brake output wire or you have an issue with your brake controller. In order to test the brake controller you will need to sever the blue brake output wire and then test for power. There should only be power with the manual override or brake pedal applied. If there is power without the manual override or brake pedal applied then you have a bad controller and it will need to be replaced. For this I recommend the Tekonsha Prodigy P2 Trailer Brake Controller part # 90885. If you do not have power when neither the manual override or brake pedal is applied then there is most likely a short on the brake output wire and you will need to trace it while checking for breaks.

If the brakes did not release when you disconnected the trailer then there could be a short between the 12 volt auxiliary battery and the brake output wire, the breakaway switch could be faulty, or there could be an issue with the braking assemblies. To make sure there is not a short between the 12 volt auxiliary battery and the brake output wire you need to trace the brake output wire from the trailer connector back to the assembly. In order to test the brakeaway you will need to use a circuit tester and probe the wire that ties into the brake output circuit. The switch could be bad which would then cause power to be sent to the brakes.

Lastly, I recommend removing the hub and making sure none of the bearings are seized or the magnets are stuck.

expert reply by: Conner L