Prodigy P3 Trailer Brake Controller Installation on 2011 Cadillac SRX

Updated 05/18/2018 | Published 05/17/2018

Question:

Hello, The output voltage on the brake pedal position switch on the SRX is between 1 and 5 volts, is this enough to activate the trailer brake controller?

asked by: Richard W

Expert Reply:

Trailer brake controllers such as the Prodigy P3 # 90195 require a brake light switch signal to trigger the controller's output to the trailer brakes. The best way to access a brakes-only signal is at the COLD side of a vehicle's brake light switch; this is the wire that carries voltage ONLY when the pedal is pressed and at no other time. The pedal position sensor will not work.

You will need to access a brake-light-only signal at the car's BCM (body control module) which is just above the driver's left knee. Find the black X4 connector and look for the white wire in position 11. This will give you the correct signal to connect at the controller's RED input wire.

expert reply by: Adam R