T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2007 Mercedes-Benz G-Class
These items fit your vehicle
2007 Mercedes-Benz G-Class
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Wiring a trailer doesn’t have to mean messing with factory wires. The Tekonsha T-One harness plugs straight into existing connectors for a clean, hidden hookup. Since it’s a plug-in design, there’s no cutting or splicing to worry about—just connect it and you’re ready to tow.
This harness includes a powered converter that keeps the trailer lights working right without overloading the vehicle’s electrical system. It draws power directly from the battery for a steady signal to the trailer’s running, brake, and turn lights. That means the lights stay bright and consistent even on long hauls.
Nobody wants wiring hanging off the bumper. The hidden plug and lead design keeps things neat by letting you route the harness where it’s out of sight until you need it. When it’s time to tow, just pull out the 4-flat connector from its spot and plug in—simple, tidy, and ready to go.
The 4-flat connector gives you exactly what most small and midsize trailers need—running lights, turn signals, and brake lights. It’s the standard setup that works with boat trailers, utility trailers, or campers without any extra adapters.
Customer Satisfaction Score:
92% were satisfied with this product
8% of customers were not satisfied
Ratings & Reviews
Great service, selection snd prices!!!
easy install
Great service
Thank you, we received it in a timely m anner!
Lengthy install time, but it works just as it should
Our order was shipped as ordered. Easy company to work with.
Worked the first time. Hasn't worked si nce.
Installed in 2020 Subaru Impreza. Works just as advertised. The hardest part is ripping out the plastic under the doors and feeding the hot wire. Expect an install of 45 min to an hour. If Subaru had a hot wire lead pre-installed in the trunk, it could be installed in under 5 min.
Fast delivery, well packaged.
The website offered a number of Wiring Kits that were supposed to fit my vehicle. However the one I picked did not fit my wire harness ( I hope they removed that one from the list). Every one was very nice and they suggested another harness, that did fit the vehicle correctly. They also provided instructions for the return of the incorrect harness. Bottom line is that it held me up an extra week, I had to pay shipping on the 2nd harness and will probably have to pay the return shipping all because the website
was wrong.
Mike L.
7/8/2019
This wiring harness is a fit for the sedan, but not the wagon model as mentioned in our fit guide.
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Gwendolyn Y.
2/3/2025
Hey Andrew. That is a bummer to hear, the harness should be lasting a lot longer than that. It is possible that the fuse in the inline fuse holder went out. If you have not checked that, I'd start there.