help installing electric brake controller

[Fishermark]

I have a 1998 Chevy Cheyenne C2500 pickup. (New to me... still getting to know it!) Someone has installed an electric brake controller in the past - it has four wires coming from it - black, white, blue, and red.

Here's how it is supposed to be wired:


Fairly straight forward.

My problem? twofold:

1. The red wire from the brake controller does not currently connect to the brake switch wiring. Instead it goes forward through the firewall and terminates to.... nothing. There was apparently room for another battery in the front of the truck. (Not sure what that's for). The red wire pictured here with the terminal end is the wire leading to the brake controller. The brown wire leads to ground.







2. I cannot find where the brake switch wire is under the dash! I can see MAYBE the switch... but cannot see any wires as they are above the column. Does anyone have a wiring diagram or any suggestions where and how to find where to splice into the brake wire?

I even took apart the dash, but there is a metal enclosure around the entire steering column area and I cannot begin to see the brake light switch nor the wires.

[Fishermark]

Finally figured it out. I ended up tracing the wires to from the third brake light and hooking up there.
Thanks!

[mkirsch]

IIRC, on my 1997 Cheyenne, the brake light switch was right there staring me in the face. Just followed the brake pedal up just into the under-dash area, and there it was, wires and all... My brake lights were stuck on and I had to fiddle with the switch.

[Fishermark]

I agree that connecting wires by function would be great... just cannot find the wire for the brakes!

[skipnchar]

My suggestion is to ignore COLORS and connect wires by function. MIGHT need a schematic but many brands actually label wires by function. Colors are not uniform even on the same brand from year to year.