T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2017 Toyota 4Runner
These items fit your vehicle
2017 Toyota 4Runner
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Wiring a trailer doesn’t have to mean cutting into factory wires. This Tekonsha T-One harness plugs right into existing connectors using a simple plug-and-lead design. No splicing or wire tracing needed, so you can get a clean install without taking apart the factory setup.
The hidden design tucks the wiring neatly out of sight until it’s needed. That keeps things looking tidy and protects the leads from weather and road debris. It’s built as a vehicle-end connector, so the setup looks stock once you’re done.
A powered converter keeps your vehicle’s sensitive electronics safe while delivering steady power to the trailer lights. It ensures proper operation of running lights, turn signals, and brake lights through the 4-flat connector—no flickering or overload issues.
Once installed, you’ve got a standard 4-pole flat connector ready for your trailer. It handles the basics—brake, turn, and tail lights—so you can tow small campers, boats, or utility trailers confidently and safely.
If your vehicle didn’t come with tow wiring, this kit fills that gap. It provides everything needed for a functional trailer light connection without relying on factory tow package parts or wiring. Plug it in, route the wire cleanly, and you’re set to tow.
This will not affect how the tail lights on your vehicle operate.
Ratings & Reviews
Connecting the harness to the tail lights on either side was easy and uneventful. My 2012 Hyundai Accent 4-door doesn't have any grommets that feed wires to the underside of car so it was necessary to drill a hole. I drilled a hole from under the car into the truck, from just behind the rear axle, soI knew I wouldn't damage anything. I bought and used a rubber grommet to line the hole to protect the wire running from the control box in the trunk to the battery. The wire leaves the truck near the drivers side rear brake assembly and I zip tied the power wire to the brake lines. The brake lines run from rear to front through a channel inset into the bottom of the car to keep them away from damage. There are a couple of plastic shields over the brake lines for added protection and I was able to lift one side of the shields to push the wire into the shields. When I got to the engine compartment I inserted a metal rod from the brake fluid module to the underside of the car and taped the end of the wire to the rod and pulled it up, cut the wire to length, inserted the fuse module, and connected it to the battery. Works perfectly.
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Barrie
5/28/2020
After a year it still works properly every time. Very pleased.