Adding 5-Way Flat to 2023 Hyundai Santa Fe PHEV

Updated 09/30/2025 | Published 05/08/2025

Products Featured in This Question

Curt Trailer Connector Adapter - 4-Way Flat to 5-Way Flat - Vehicle End

(103)

$12.90

Hook Probe Circuit Tester

(60)

$13.33

Question:

Need a 5 flat vehicle connector for a 2023 Santa Fe PHEV. This somehow taps into the back up lights to stop activation of the surge brakes when backing up. Presently have a 4flat from you. Need help locating the backup light wire.

asked by: Paul G

Expert Reply:

Hey Paul, welcome back! To add a 5-way to your 2023 Hyundai Santa Fe PHEV you need the Curt Trailer Connector Adapter - 4-Way Flat to 5-Way Flat # C57187. Unfortunately, we do not know the exact location or color of the reverse light circuit wire on your vehicle. The wire is likely in a similar location to the one in the installation video attached below. However, you will have to use a tester like # PTW2993 to identify the correct wire and tap into it.

expert reply by: Robin H

Curt 4-Way to 5-Way Installation
(click to enlarge)

Robin H.

9/29/2025

Hey Paul, did you manage to find the backup light wire on your Santa Fe PHEV and get the 5-way connector set up? I'm curious to know how it worked out for you, as it might help others with a similar setup.

Paul G.

9/30/2025

@RobinH discovered if I plug the trailer 5 pin (by flipping it so the ground is not connected) into the vehicle 4 pin and turn on the vehicle lights the trailer surge brakes will be released. The few times I need to do this is OK with me for now.