Finding Brake Switch Wire to Install Brake Controller on a 1989 Chevy K2500 Pickup

Question:

hi i have a 1989 k2500 im putting a break controller in and i see you guys put the break signal wire to the white wire witch i did but when i turn the head lights on its also sending the signal to put the breaks on to and cant find any other wire to tap into for the break signal wire

asked by: Jake W

Expert Reply:

The white brake switch wire was the common brake light only wire on 1992 and newer Chevy trucks and SUVs but not on the 1989 C/K series trucks. I am not certain which brake switch wire you will need so the only way to know is to test the brake switch wires using a circuit tester such as # PTW2993.

The truck key may or may not have to be in the on position. You are looking for the wire that only has power when the brake pedal is pressed. If the wire also has power with the headlights or turn signals on then it is not the correct wire.

If you cannot find a wire that will work then check the fuse panel(s) for a stop light or CHMSL fuse. As long as one of those is the only item on the fuse you can use a fuse tap or tap into that circuit for the brake light only connection for a brake controller.

expert reply by: Michael H