Is Just 3-Connector Relay Harness Available for 2018 Nissan Frontier
Updated 02/03/2026 | Published 07/27/2024
Question:
I ordered a towing package from another vendor for my 2018 Nissan Frontier with 7way connector and 4way connector. It plugged in fine under the truck bed but I t did not come with the wiring to connect the relay under the passenger side panel. Can I purchase only that part with the 3 plugs on one end and the one that plugs into the truck under the passenger side dash?
asked by: Leanne C
Expert Reply:
Hey Leann, thanks for reaching out!
We've had people reach out about this in the past, but unfortunately the only way to get the extra wiring in the T-One Vehicle Wiring Harness Kit # 118525 for your 2018 Nissan Frontier is to purchase the whole kit. I'm not sure why the wiring manufacturers don't sell the relay side separately but they don't.
What you might want to do is get this kit and just keep the 4-Way wiring part in your glove box or a safe place as a backup just in case.
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Robin H.
2/3/2026
Hey Leann, did the full T-One wiring harness kit end up giving you the relay connection you needed for your Frontier? Knowing how it worked out could help others who run into the same issue.