I'm hooking up a 7-way wiring harness on a 2000 Cherokee. Does anyone know which wire is the cool wire coming off the brake control switch? I need to install a trailer brake controller and it should be hooked up to the cold side.

7 pin plug wireing

1. (White) = Ground
2. (Blue) = Electric Brake
3. (Brown) = Tail Lights
4. (Black) = +12Vdc
5. (Yellow) = Left Turn
6. (Green) = Right Turn


To find the switched (cool) side of the brake light switch connect the + side of a volt meter to the wires at the switch one wire at a time and the - wire of the meter to ground.

One wire will give you 12v the instant you touch it, this is the =12v (hot) side. The other wire will become hot only when you push down on the brake pedal. This will be the switched (cool) side of the switch, and be the wire that activates the electric brake controller.

Thanks for the info. Everything is hooked up and I'm in business.

Your welcome.