Should 2023 Nissan Frontier Passenger Side Relay Harness Already Exist for T-One Wiring Kit
Updated 11/03/2025 | Published 01/31/2025
Question:
I received my order today and was excited to install the hitch on my 2023 Nissan Frontier SV. Installation was quick and easy but I have a question about the harness with the relays. Once I removed the passenger side side panel there wasn’t an empty connector behind the panel. One connector looked like the correct one but it has a few wires already plugged into it. I’m going to pick up a trailer tomorrow. My questions are will the trailer lights work? Should I unplug the existing wires and plug in the harness that I bought from Etrailer? Thank you so much for your time I’m sorry I didn’t even think about taking a picture. I can if it will help.
asked by: Andy K
Expert Reply:
Hey Andy, thanks for reaching out and also for your recent purchase!
If there is already another harness with relays plugged into the spot that the harness from the T-One Vehicle Wiring Harness # 118266 should plug into on your 2023 Nissan Frontier, then what I recommend doing is installing the rear 7-Way harness and testing the pins to see if they show power or not. If they don't, it's worth replacing the passenger side harness with the one that came with the kit, but if they do, then you can just hold onto that extra harness in case you end up needing it in the future.
What trailer did you end up getting?
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Jon G.
11/3/2025
Hey Andy, how did things go after you tested the 7-way harness on your Frontier? Did the trailer lights work correctly once you checked the power at the pins? Your update could make it easier for others wiring the same setup.