Troubleshooting Nissan 7-Way Wiring Where Brakes are Locked Up When Trailer is Connected

Question:

Who do you remove the pin in the plug to switch them

asked by: Steve

Expert Reply:

The issue is that the electric brake signal wire and the 12V battery charge wire are reversed in the main vehicle harness. This is the reason that the trailer wiring harness you have has a constant 12V signal on the brake controller output circuit. Since there is constant power to the brake controller output in, there should be no signal on the 12V battery charge pin. The easiest solution is to cut the wires leading to the output pin and the 12 volt pin on the 7-way and reconnect them backwards. This is what I would do and what I recommend.

I attached a diagram of how a 7-way is pinned out as well. The relevant pins are in the 1:00 and 5:00 positions.

expert reply by: Jameson C