Installing Tekonsha P3 Trailer Brake Controller on a 2010 Toyota Tundra with Factory Tow Package

Question:

I would like to connect Tekonsha P3 # 90195 to my truck using OEM pigtail connector provided with the truck. Could you please provide specific directions wire/color to wire/color between P3 wiring and toyotas connector.

asked by: Jakub

Expert Reply:

I can tell you that on a Tekonsha P3, # 90195, the wiring colors and functions are as follows:

White = ground
Black = 12 volt power
Blue = output to trailer brakes
Red = in from stop light

You can use a circuit tester, like # PTW2993, to test the wires on the factory harness for 12-volt power and stop light signal. To test for the blue wire, you will need to send power down the remaining 2 wires on the factory harness and then test the 7-Way connector at the back. The wire that shows power at the 7-Way when power is applied to the wire would connect to the brake controller blue wire.

To send power down the 2 wires, you can use a separate battery or use a jumper wire from the 12 volt wire.

The last wire is ground but the Toyota factory ground has proven to not be sufficient for brake controller use. I recommend grounding the brake controller white wire to a bare metal surface in the vehicle cab.

The easiest thing to do would be to use the brake controller with vehicle specific wiring harness # 90195-3040-P. The wiring harness that comes with this set has one end that plugs into the brake controller and one end that plugs into a port on the vehicle. The ground wire is connected to a metal surface separately. I have incldued a link to a video showing the installation of a brake controller using the harness.