"Standard" Wire colors to the controller (Tekonsha and others):
- Black, Battery Positive to controller
- White, Negative Ground for Controller
- Blue, Brake feed from controller to Trailer plug at back of truck
- Red, tap into truck Brake light switch signal to tell controller to apply brakes
I have seen many factory harnesses that have a extra wire for dash lights (usually brown). Most controllers do not have "dash lights" so don't hook that wire up.
Installing a brake control unit isn't very difficult. This task is made even easier if your tow vehicle is a late model and comes with a 7 Way Connector as part of the towing package.
In this case, installation is as simple as mounting the brake controller in a convenient, easy to reach place, usually under the dash, just above your right leg and connecting the wires from the brake control to the wiring harness and then plugging the harness into the harness located under the dash.
Most newer vehicles equipped with towing packages are now providing a wiring harness which looks similar the ones in the picture below depending on the make of your vehicle:
On Chevy and GMC trucks, with the tow package, the factory provided a plug under the dash to connect the brake controller. On the trucks I have done, it is a plug, located in the fuse box, just above and behind the parking brake foot pedal, up under the dash. You must have the factory plug harness to plug in (I sell these, if you need one, hint, hint)
