Running Jumper Wire for Electric Brake Assemblies on Trailer
Question:
With my trailer the wires coming from brake box located on the trailer is coming down the passenger side of the trailer. The two wires coming from brake drums comes out on the left side. I was planning on running a wire from the right side of the trailer to the left side and attach to the wires coming from the brake drum. Do I ground the wire coming down the trailer on the right and not attach the one wire on the left coming out of the brake drum or run a wire from the right to the left and ground on that side.
asked by: Scott H
Expert Reply:
Since the wiring on your trailer is just running down the passenger side you can indeed connect it to the power wire on the passenger side brake assembly and then run a jumper wire from there to the assembly on the driver side. When doing this you will still want to ground each brake assembly separately to the trailer frame. This will make it so that you only have the power wire running across the trailer to the brake assembly on each side.
I recommend using 12 gauge wire like # 12-1-1 (sold by the foot) for the jumper wire.
I have attached an image to give you a better idea as to how the wires will run. It is for a tandem-axle application but the idea is still the same for a single axle.

Products Referenced in This Question
Product Page this Question was Asked From
35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 31 Feet and Longer
- Plug and Lead
- 4 Flat
- Optronics
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