Tip for Finding Stoplight Circuit for 2021 Kia Sedona for Brake Controller Install

Updated 10/22/2025 | Published 03/27/2025

Products Featured in This Question

Redarc Tow-Pro Liberty Brake Controller w/ Universal Wiring Harness - Dash Knob - Proportional

(2506)

$217.00

Hook Probe Circuit Tester

(60)

$13.03

Roadmaster Universal Stop Light Switch Kit

(622)

$126.53

Question:

Hello, I am installing the Redarc brake controller, but I do not know what wire is the brake light for the red wire connection. I have a 2021 Kia Sedona Ex. How do I find this out? A NCV tester has not seemed to work. How do I find this information? Thank you,

asked by: Grant M

Expert Reply:

Hey Grant, did you test all of the tires that run to your stoplight circuit with your tester? If not, that is the place to check. Since you used a non contact tester and some say those aren't always reliable I would try again with a probing tester like our part # PTW2993. You will be looking for a circuit that only has voltage when the brakes are applied.

Another option is a universal stoplight switch like the part # RM-751000 which you'd install at the brake pedal and it will give you the stoplight circuit you need for the red wire of your controller.

expert reply by: Jameson C

Jameson C.

10/22/2025

Hey Grant, how did things go finding the correct brake light wire for your Sedona when hooking up the Redarc controller? Your results could really help others working through the same wiring step.