How to Identify Correct Brake Light Switch Wire for Brake Controller Installation in 2017 Pacifica

Updated 05/24/2017 | Published 05/22/2017

Products Featured in This Question

Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional

(2763)

$159.00

Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires

(3397)

$121.25

Question:

I have purchased everything listed by you for my 2017 Chrysler Pacifica and need some guidance on the location and description of this cold side brake wire Can you please help?

asked by: Carl S

Expert Reply:

The cold side of a brake light switch is used as the trigger signal to activate a trailer brake controller like the Prodigy P2 # 90885. The controller installation kit you purchased, part # ETBC7, includes a probe-style circuit tester that allows you to determine which of the wires at the brake light switch is connected the to cold side of the switch. The correct vehicle wire to connect to the RED wire on the controller is the one that goes hot ONLY when the brake pedal is pressed, and at no other time or with any other function engaged.

Auto makers can change the color of wiring used pretty much at any time and without notice (they don't shut down the production line if they run out of one wire color - they use a different one) so testing with the circuit tester is the best route to find the correct signal wire. The other leads are ground (white wire) which connects to the battery negative terminal; output (blue wire) that connects to the 7-way; and 12V power to the controller (black wire) which connects to the battery + terminal through a circuit breaker.

I have linked both an article and video covering installation of the # ETBC7 kit.

expert reply by: Adam R