Brake Controller Wiring on Motorhome

Question:

Trailer brake controller on a 40’ diesel pusher coach. Instructions for the controller specifies 12 ga wire for the brake magnets. I am running wire over 40’ of distance. Do you think 10ga or 8 ga would be better. Also there are brakes on both trailer axles of my car hauler. On the last coach that I outfitted I used a 50 foot 10 gauge 3 wire extension cord and twisted the two the black and white together and used the ground as a ground between the coach and trailer. It is difficult to run the cord through the bus compartments, so I merely zip tied it to the underside of the coach. The extension cord has its own insulation, so what do you think?

asked by: Earl T

Expert Reply:

To answer your first question about installing the Prodigy P3 # 90195 I recommend going with 10 gauge wire # 10-1-1 over that distance.

As for your other question, you can zip tie your wires to the underside of the coach but you are going to want to use Heat Shrink Butt Connectors # DW05745-10 at your connection points to seal your ground and hot lead wires and protect them from dirt, water and the like; also be sure you have a proper ground on both your coach and trailer.

expert reply by: Kyle S