Trailer Brake Wiring Help Needed

[ACOOKMadison]

Hello all. I have a 2011 3100 rl and we are having an electric trailer brake wiring problem somewhere between the junction box under the pin box and the wheels. We are supposed to be on our winter getaway amd are delayed trying to get this fixed. 2 questions..
1. Does the Blue trailer brake wire go thru the converter / fuse box somehow or just straight back ti the wheels?

2. Can I bypass the wiring from under the coach by running a new hot and ground from the brake wires at the wheel to the 7 pin plug. Just the electrical brake wire? Anybody have any help?!

Thanks so much in advance.

[Carl n Susan]

Originally Posted by ACOOKMadison

1. Does the Blue trailer brake wire go thru the converter / fuse box somehow or just straight back ti the wheels?

AFAIK, yes, the blue wire goes from the junction box down into the front compartment and back to the brakes.

2. Can I bypass the wiring from under the coach by running a new hot and ground from the brake wires at the wheel to the 7 pin plug. Just the electrical brake wire?

Yes you can run a new wire set to the brakes. A not uncommon problem with brake wires occurs inside the axle where the wires get chaffed. Some of us have run the wires on the outside to avoid that problem.

[rohrmann]

The trailer brake wiring does not go into the trailer wiring but is strictly powered by the tow vehicle. The emergency breakaway switch does use power from the onboard battery, but only if the breakaway switch is operated.


It sounds like you have a broken wire going to the brakes which just takes some checking for power at each wheel. If none of the wheels are getting power, then it will be between the pin box and the first junction where the wiring splits to the from axle. Another place that causes problems is the wires inside the axles can wear through the insulation and grounds out to the frame of the trailer.
LOOKS LIKE I WAS A SPLIT SECOND TOO LATE

[Daryles]

Hope this helps

[laverdur]

Not sure what exact problem you are trying to solve but, if your 5er brakes are intermittent I'd suspect chaffed brake wires inside the axle. Road vibrations cause the wires to short to the axle tube when underway. Cut the internal wires at both ends and run wires on the outside of the axle tubes. Secure the new wires with zip ties or encase the wires in plastic wiremold and zip tie the wiremold to the axles.

[Foldbak]

Or corroded connection at the 7 way plug. Been there done that so many times!

[BB_TX]

Also check inside the junction box on the pin box. The wires from the 7 pin cord are wire nutted to the trailer wiring. Possible a nut came loose.

[laverdur]

If you suspect corrosion on the 7-pin connector, I have found Deoxit to be excellent.