Tips on Finding the Brake Light Wire on Brake Switch for Brake Controller Install, 2007 Lexus RX400H
Updated 06/28/2011 | Published 06/26/2011
Question:
Hi! I purchased Prodigy brake controller and the wiring kit for a 7 pole braking package a few weeks ago. Wired it all up but can't figure which of the four wires coming off the brake pedal is the correct wire to connect to.
asked by: Al
Expert Reply:
Finding the correct wire on the brake switch can be tricky, but I can give you some tips on how to find it on your 2007 Lexus RX400H. First, if you do not already have one, you will need a circuit tester like # PTW2993.
You have probably noticed several wires coming in and out of the brake switch. With the circuit tester, probe the wires until you find the one that carries a signal ONLY when the brake pedal is pressed.
If you find a wire that has a signal at any other time, like when the headlights are on or when the turn signals are engaged, it is not the correct wire. You need a dedicated brake light wire only.
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