Brake Lights Stay After Installing the Brake Controller
Updated 10/29/2025 | Published 03/24/2025
Question:
I wired up the Primus IQ brake controller to my 2019 Chevy Colorado and when I plugged in the controller the brake lights on the truck were on. Can you tell me where I could have made my mistake. I am truly certain it is wired correctly as per the instructions. Thank you.
asked by: Rick
Expert Reply:
Hey Rick! It sounds like the Primus Brake Controller item # TK90160 was not wired correctly to the cold side of the stop light switch. I recommend double-checking that and using a circuit tester like item # PTW2979 to find the wire that only has voltage when you press the brake pedal.
I have linked a couple of installation videos below that we did with the Primus item # TK90160 on the same generation Colorado's. If you have any additional questions feel free to throw them into the comment box below.
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Jerred H.
10/27/2025
Hey Rick, how did things go after you checked the cold side of the stop light switch on your Colorado? Did using the circuit tester help you track down the right wire? Your update could make it easier for others wiring the same brake controller.