How Many Wires Run to the Front of Vehicle When Upgrading From 4-Way to 7-Way

Question:

I am installing a flat 4 pin wiring harness and a 7 way round connector with a brake controller. Can I connect the black auxiliary wire from the 7 way to the black wire from the control module under the driver side tail light? or do I have to run a total of 3 wires from the back to the front?

asked by: Mark G

Expert Reply:

When installing a 7-way using something like the # ETBC7 you only need to run two wires to the front of the vehicle from the back. One wire for the electric brake output which will go to your brake controller and the other for your 12V power.

I'm not sure what adapter you are using, but 4 of the wires will attach to the existing 4-way. You would then typically run the blue wire to the brake controller, the black wire to your battery with a fuse or breaker for 12V power, and the yellow auxiliary wire would be for your reverse lights.

I have attached some pictures showing the wiring that you may find helpful. I also attached an installation video of our # ETBC7 kit along with a helpful article on 7-way wiring for your reference.

expert reply by: Robin H