Troubleshooting Curt Trailer Wiring Not Working for a 2017 Hyundai Santa Fe

Updated 06/04/2025 | Published 05/31/2025

Question:

My 7-pin trailer wiring stopped working on the vehicle side. I tested it with a different vehicle and the trailer side works fine. I have the Curt factory wiring harness for a 2017 Hyundai Santa Fe XL. The brake controller and constant battery power wiring seems to be functioning fine. It is just the lights that arent working. Is it possible that it is the control unit on the harness that is not working? All fuses have been replaced and it has blown the fuse several times that is off the wiring harness/control unit. I was wondering if I can just replace the factory wiring side and leave the electric brake and power charge line as is. Thanks!

asked by: Scott S

Expert Reply:

Hey Scott, thanks for reaching out!

What wiring kit do you have on your 2017 Hyundai Santa Fe? The Curt T-Connector # C56332 would be somewhat easy to replace, but it only has a 4-Way flat connector.

Is this the type of wiring you're wanting to replace?

expert reply by: Jon G

Scott S.

6/3/2025

Thanks for the reply Jon. If I cut off the 4-pin connector could I not just wire those directly to the 7-pin connector/adapter? Leaving the constant power connections for the electric brakes and battery charge lines as is? Thanks

Jon G.

6/3/2025

@ScottS You absolutely can do that! I wasn't 100% sure what you had or what your confidence level was with wiring, but yes, you can definitely go that route.

Scott S.

6/4/2025

@JonG thanks Jon - I will order the harness you suggested

Jon G.

6/4/2025

@ScottS Sounds good - let me know if you end up having any other questions or ideas!