Instructions to Wire a Trailer for Electric Brakes
Updated 05/29/2024 | Published 03/20/2015 >
Question:
I have a black and white wire coming from the brakes, I dont know where to plug them in the box to truck lead, color for color
asked by: Larry B
Expert Reply:
It sounds like you are speaking of the wires for the brake magnets. If this is correct, you will need to connect one of the wires to the brake controller output wire on your trailer connector and the other wire will need to be grounded to a clean metal surface on the trailer. I have included a diagram for you.

Sam
5/26/2024
Hi Leah. Found this and it is super helpful. I just wanted to ask, my understanding is that there is no polarity as such with the electric trailer brakes. So any wire can be the ground. Can I ground any of the two to any suitable surface on the trailer frame?

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Haden S.
6/1/2020
W/ a 4 wire harness (green, yellow, brown & white). How do you wire the electric brakes from the junction box to the hubs? Which wires Tie together to get function? I have 2 green wires coming from the hub, a red & black wire coming from the axle to tie into the passenger side brakes & the white & black brake wire. How do these all tie together from the junction box to get the brakes to function?? Thank you.