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Tired of complicated wiring setups? The T-One Vehicle Wiring Harness by Tekonsha makes adding a 4-way trailer connector a breeze. Simply plug it into your existing vehicle wiring without any cutting, splicing, or tapping required. It's a seamless integration that’s perfect for car enthusiasts who enjoy DIY installations but want to avoid unnecessary hassles.
Worried about compatibility with different adapters? The ModuLite technology ensures smoother connections by integrating tail light conversion, making it compatible with 5-pole, 6-pole, and 7-pole adapters (sold separately). This feature streamlines the intricate wiring differences between your vehicle’s 3-wire system and the trailer's 2-wire system, ensuring everything works in harmony.
Protect your vehicle’s wiring system from overload with the circuit-protected ModuLite HD module. It reduces strain by managing power for stop/turn lights (up to 5 amps per circuit) and tail lights (up to 7.5 amps per circuit). You can drive with peace of mind knowing that your system is safeguarded against electrical issues.
Ensure long-term performance with a dedicated dust cap for your 4-way flat connector. By using a small amount of grease on all electrical connections, you’re actively preventing corrosion, ensuring your harness stays in top-notch condition, especially in harsher climates or moist environments.
Keep your vehicle’s sleek look intact by neatly stowing the 4-way connector in your rear cargo area when not in use. This solution keeps everything tucked away, maintaining your vehicle's aesthetic while offering easy access whenever you need to hitch up and go.
This custom-fit T-One connector plugs into your vehicle's wiring harness, which is located behind an interior trim panel in your rear cargo area, on the passenger's side. Once you've plugged in the connector, you will have to route the harness through the jack storage compartment to the center of your vehicle. Before plugging the included 7-way socket into the tow harness, locate the fuse box under your hood and insert the provided fuses.
Once installation is complete, the 4-way connector will be stowed in your rear cargo area.
It is recommended that you use a small amount of grease on all electrical connections - the plugs on your automobile and the 4-pole connector itself - to help prevent corrosion.
A ModuLite power module is built into this T-One connector. Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your vehicle's three-wire system need to be combined so they are compatible with the wiring system of your trailer. This power module functions as a tail light converter to combine the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights.
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The hitch was easy to install and looks great. There was only one problem. I received the hitch with the wrong hardware kit. Customer support was great and shipped me the correct hardware at no cost
The wiring harness was very easy to install and came with excellent, clear instructions.
My suggestion for product improvement would be the addition of a connector on the 4-wire cable near the converter. This would allow routing of the cable through the factory-provided hole that's intended for this purpose. The 4 flat connector will not fit through the hole. For a nice clean install as shown in the picture, I had to cut the wire and reconnect them inside the vehicle.
Perfect fit and easy installation. The videos are so helpful.
Watched your installation video. Included screw too small for ground wire (2021 Honda Van vehicle hole). Have to drill new hole. Everything was straight forward and easy. About 10 minutes from start to finish. Tested with Circuit Tester. Worked perfectly…many thanks
Easy to install, used the provided instructions as well as YouTube videos. Very pleased!
Timothy
7/15/2025
Great, easy to install. Have not used it, however tested it with trailer wiring tester.
Nick S.
7/15/2025
I purchased the wiring harness for my 2019 Honda Odyssey. It is very easy to install and works great. It comes will all screws and fuses that are required. Great product.
Good instructions, simple install. Plug and play capability.
Love being a supervisor. Watched my oldest daughter 35 install this on her own. I was the one passing the tools. Excellent product and directions on trailers video.
Plugs right in. Simple installation.
Installed on 2020 Honda Odyssey. Fast shipping even a few days before Christmas! Super easy to install. I read the instructions and watched a few different YouTube videos as a cheat. The uHaul video shows how to route the harness wires through a small existing vent on the driver's side which I did. I also routed the wires above (inside) the bumper and easily pulled just enough of the harness out to cable tie to the hitch right at the receiver. Great purchase and easy installation.
Easy to install, but I took it a step further. Instructions say to run the wire out the door, and close the door on the wire. I removed the brake/directional light and ran the wire out an unused panel plug, then down under the bumper. This will take an extra 30 minutes but all the wires will be hidden.
Joshua was so helpful with all my orders and getting things right. I would definitely order from eTrailer again thanks to Joshua!!!
Works as expected with good instruction s.
Robert J.
2/26/2025
The wiring harness is easy to stow away and has worked every time with no issues on different types of private and rented trailers.
Ordered at 2:00pm delivered the next day 1:00pm product was exactly as advertised on quality and ease of installation
Gwendolyn Y.
3/13/2025
I think that's a new record! Are you going to be towing a new trailer with it?
Couldn’t believe how easy it was to install. Great fit guide and instructional video on the item page.
Easy install for the ‘19 Honda Odyssey. Everything you need for a factory fit. Visit YouTube U-Haul video for technique to easily pass harness through to outside and zip-tie cable to your hitch. Extra length, too.
Very good product. Instructions were more than adequate. I was able to route it under the trim panels and down to the hitch with only minimal trimming.
Instructions were clear, good quality p roduct.
Works as expected.
I installed this on my 2023 Odyssey van twelve months ago. Installation was easy. I’m very pleased with the product.
Excellent in all ways. It was Easy to install with good directions.
Anthony
3/23/2025
Perfect
Jerred H.
3/23/2025
One plug,push in several fuses add a ground screw very easy. Fuse diagram could have been more representative of my actual fuse box. Overall EXCELLENT!!!
Easy to follow instructions, good quality, no issues. Tucks away nicely when not in use.
I had a difficult time installing. I could not identify the extra tail light wire in the panel and had to fish a wire from the tailgate to the harness.
Larry
4/26/2024
Great. No issues.
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Geoffrey
11/15/2025
The wiring harness and circuit has worked flawlessly since I installed it. The materials are still in great shape and are not showing any signs of aging. I expect the wiring will last for the lifetime of my vehicle.