Question:
On a 2018 Toyota Highlander, what wire on the brake pedal connector do I splice the brake light signal into for the activation of the trailer breaks?
asked by: Ben S
Expert Reply:
When installing a brake controller, the only way to determine the cold side of the stop light switch on any vehicle, including your 2018 Toyota Highlander, is to use a circuit tester such as the very handy Cordless Circuit Tester # PTW2979 and find the wire that only has voltage when you press the brake pedal.
If you take a look at the linked video we did installing the Tekonsha Prodigy P3 Trailer Brake Controller # 90195 with the Pigtail Wiring Harness # 7865 on a 2018 Toyota Highlander, if you go to about the 19:20 mark you can see it was a green wire, but yours could be different so you'll need to test it with a circuit tester.
The other parts you will need to install this brake controller is the T-One Vehicle Wiring Harness # 118449 and Universal Installation Kit for Trailer Brake Controller # ETBC7.
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
Pigtail Wiring Harness with Diode for Tekonsha and Draw-Tite Brake Controllers
Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires