Trailer Brake Install

Happy New Year to you and yours,
Tried installing Tekonsha P3 in my 2018 Tundra. They sent a harness that is useless. There is no aftermarket plug and play for my vehicle.
Am I better off to reinstall OEM trailer brake and let Toyota deal with it or does anyone have another harness solution?
Thanks for your help.

 

This might help you.
https://www.etrailer.com/question-311767.html

 

Unless it has changed, there is no "correct" plug-n-play harness available for aftermarket brake controller on 2018+. You can simply lengthen some the wires in the supplied harness to reach the passenger side of the dash. You'll need to connect some of your harness wires to an IBC harness connector on the right end upper dash.

The thread below is for the 4.6L, but the details are the same unless your truck came with the factory IBC controller. In that case, the factory IBC harness connector on the right side of the dash may already have a harness for the IBC plugged into it. If you disconnect that harness, you may still get warnings on the dash. Others have fixed that and can probably help you with that if your truck came with the IBC.

https://www.tundras.com/threads/2018-tundra-with-4-6-engine-trailer-brake-install.25884/