Installation of 4-Flat Wiring Harness on 2019 Nissan Frontier

Question:

Can you tell me how to go about installing this 4-way on 2019 nissan frontier? for reaosns i cannot understnad nissan makes this type of thing way harder than necessary. im not sure what their deal is.

asked by: Doug E

Expert Reply:

Installation of the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C56225 that fits your 2019 Nissan Frontier (without a factory connector) is very straightforward, but installing a harness on a Nissan does require the use of relays, which are included with this kit.

Start the install by attaching the relays, with the blue ones going on the white plugs and the brown one going on the brown plug. Then simply locate where you need to plug in the connectors and that's all there is to it. I have added a link to a video of this harness being installed so you can see firsthand exactly how it is done.

expert reply by: Kyle S

Ricky H.

7/20/2020

why do you have to use the relays ? on harness 2019 nissan frontier using 4 pin harness plug in rear harness on frame to trailer not work all lights without relay harness?

Chris R.

7/26/2020

The relays need to be added to actually activate those circuits on the truck. If the trailer lights aren't working and you didn't install the included relays, that would be why.