Where Should Red Wire On Tekonsha Prodigy P3 Be Connected On 2019 Toyota Highlander?

Question:

Hello, I read on a previous thread here that the best way to connect the red brake light trigger wire for a brake controller is to connect it to the brake pedals brake light switch. However, I cannot find anything that says how to find the correct wire to connect to on the brake pedal for my car listed in the subject. Also, is the brake pedal really the preferred connection method? With all the safety features on this vehicle I would think there would be a better connection method? The brake pedal is not the only feature that stops these cars. Can you please advise where the best and closest location is to the brake controller to attach the Red wire?

asked by: John C

Expert Reply:

To install the Tekonsha Prodigy P3 # 90195 on your 2019 Toyota Highlander Hybrid you are correct that you will connect the red wire from the included pigtail to the cold side of the stop light switch on the brake pedal.

This is the preferred method, as this switch is what tells your brake lights to come one when the brake pedal is pressed, and allows the trailer brake controller to only send power to the brakes when the pedal is pressed. Also this circuit is a dedicated circuit, so there are not other functions tied to it like other points you mentioned

The # 90195 includes a butt connector that you will use to connect to that wire. You will cut the wire off the factory connector use the butt connector to reattach the wire with the red wire on the pig tail as you can see at the 22:30 minute mark of the included video.

You will need to use a circuit tester like # PTW2993 to make sure you are connecting into the correct wire. The wire you need is the one that only has power when the brake pedal is pressed.

I included a video of the # 90195 being installed for you to take a look at.