Will The Curt Wiring Harness C56184 For A 2014 Hyundai Santa Fe Power Incandescent Lights?

Updated 08/03/2026 | Published 07/28/2026

Question:

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector Part Number: C56184 Will this work for a trailer with the old-fashioned incandescent lights, or is it assumed to be LED lighting?

asked by: David L

Expert Reply:

Hi David!

The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C56184 for your 2014 Santa Fe will actually work with LED and incandescent lights on a trailer. The black wire (upper right corner of the included image) will need to be connected to your battery for needed power, and that power will help get enough juice to run incandescent lights on a trailer as well.

What kind of trailer are you going to be towing? And what will you be hauling?

expert reply by: Lazer S

Curt Wiring Harness C56184
(click to enlarge)

David L.

8/3/2026

The issue I am having is the trailer - old, no brand name, works well with my Ford, but doesn't work on the Santa Fe. At best, I can plug the trailer into the Santa Fe, check the lights (everything working), then they turn off completely. When checking with a multimeter at the vehicle output, I measure only .63VDC. Wait a few hours, and I am back to 13.8VDC. Plug in the trailer and go down again. I assume there are resettable thermal fuse(s), so it sounds more like a larger-than-designed power draw. I have replaced the trailer wiring and lights. I've gone through the grounds on multiple occasions. Changing the lights to LED would be less power draw.

David L.

8/3/2026

Just to clarify, I changed the light fixtures with newer incandescent light fixtures; I have not gone the LED route yet.

Lazer S.

8/3/2026

@DavidL That is definitely odd. It sounds like the issue is on the vehicle side instead of the trailer side. I know you said you checked the grounds on several occasions, but have you checked the ground on the vehicle? If so, something is indeed going on with either you fuses (factory wiring) or the harness is bad and needs to be replaced (aftermarket). If you have factory wiring, I would check all the fuses related to towing. These should be easily found in your owner's manual. It wouldn't hurt to check every one of them. If your harness is aftermarket, you can use your volt meter to check the 12v wire going into the black converter box from the battery to make sure you are getting constant 12 volts. From there, check the brown running light wire coming out of the converter box with the vehicle on (with the running lights also on). If you are not getting 12 volts at the brown wire doing this, the box is indeed bad. There isn't a way to fix this as they are sealed, so it will just need to be replaced.