T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2024 Mini Cooper
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2024 Mini Cooper
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Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring. Powered ModuLite reduces strain on wiring system.
Features:
Specs:
Installation
This custom-fit T-One connector plugs into your vehicle's wiring harness, which is located behind the driver's-side and passenger's-side tail lights. You will have to remove the tail light assemblies to access this harness. Once you've plugged in the T-connector, run the hot lead up to your car battery. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery and insert the provided fuse.
Once installation is complete, the 4-way flat connector will be stowed in the jack storage compartment of 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. Note: This will not affect how the tail lights on your vehicle operate.
With a ModuLite, your trailer's lights will be powered without overloading your vehicle's electrical system. Because the module draws power directly from your car's battery and bypasses the electrical routes that are used by a basic wiring harness, there is virtually no draw on your tail light circuits.
California residents: click here
I’m not especially handy, so I figured I would have several challenges getting this installed and working. Instead, I was pleasantly surprised that installation pretty much went as described in the directions. The mod I made was that, since our 2020 Sienna XLE AWD has a cigarette adapter in the trunk, I powered the system from that instead of routing power all the way to the car battery. Towing 3 small laser sailboats from FL to MI, and 2/3 through the trip everything still functions flawlessly
Excellent kit with all of the stuff I needed for my 2017 Sienna for an easy install. The quick connectors into the factory wiring to the tail lights is so much better than trying to tap into the wires. I stick with Tekonsha because they seem to work the best.
I was able to install and found the video helpful. I was able to trim the under panel and get the wiring done so much easier with the video that I used.
Now I need to get the in dash brake controller and the 7-way setup to have brakes just in case we tow my son's classic 1983 Coleman tent trailer which does have brakes.
This worked out great! I absolutely love that they provide a video of how to install it and shows what you need, need to do, and what you'll run into. I had to get creative in making sure the wire that runs from the back to the engine battery was going along a good path that might not get road damage. The rear lights were easy to come off and connect to. The interior panel was easy to take off as well to run the wire underneath. I like that the wire is stored away in the panel door and gets pulled out only when needed to be used because it easily hangs out the back door without any issue.
Installation of the hitch, wiring,rear bike rack, and new roof rack towers went well. I didn't set any speed records, but I was more concerned with doing no damage on a new 2019 Toyota Sienna AWD van. The hitch fit up well per instructions except that I was able to work around the exhaust without lowering it. Underbody panel and rear fascia did both need to be removed. Very happy with the end result. The new van is now set up to haul the bikes and canoes and move my log splitter.
I ordered a hitch and the wiring for my new 2015 sienna minivan. The parts came quicker than I could have hoped for. The video instructions made the installation easy, especially since my van was a week old and I really didn't want to mess it up. I have been using the van to tow with for a year now without any troubles. Thanks Etrailer!
Quality and fitment of products was excellent. Highly recommend install videos on etrailer. The shipping time was very slow. I had some items price matched and that delayed processing a week or more.I provided all links to competitor's products. Very close to month before I received product (it was in stock). That is why I didn't give it an excellent rating.
Very easy to install. Total wiring time = 45 min. I did not take apart the rear panel by the driver side taillight to run the wire harness. It was a little difficult to fish through due to the size of the connections.
This was so easy to install with the helpful video. The worst part of the install was jacking up the van to get under it for the power cable.
Nice, clean installation on my 2017 Toyota Sienna. I ran the wire to the battery on the inside of the vehicle. Run the battery wire to the driver's side of the vehicle using the same path as the wiring for the driver's side rear lights. You can then tuck the wire under the trim up to the door sills. Remove the door sills and there is space for the wire. Remove the front kick trim and run the wire behind it and then zip tie to other wires as you run it over to a rubber grommet on the firewall in the area above the gas pedal. There is a small nipple on the grommet on the engine compartment side of the firewall. The nipple is there for the purpose of running a wire to the battery for whatever application may need one. Unclipping the top of the air filter casing will allow access to the rubber nipple. Cut off the end of the nipple and run the wire thru the grommet. Make sure to use a sealant where the wire enters the engine compartment to prevent water from entering the vehicle. You will need approximately 3 feet of additional wire. I spliced the additional wire inside the vehicle just before it entered the rubber grommet.
I guess the packing method is "throw it in a box and hope it gets there. Hopefully etrailer packaging/shipping sees this review and can add the $3 in styrofoam to protect the hitch from going through the box.
Install was easy, I watched the instruction video about 3 times and kept it up on my phone to verify my connections when it was time. I had the job complete including all cleanup and mounting the electrical connection to the hitch in about 2/12 hours. I took my time to verify no damage was done to our new sienna.
Easy installation in the jack storage area. Found a open spot to run power wire throught a harnes grommet so I could run power back to the converter inside and under trim
I turly love that the hitch is under the back guard, very low profile the only thing was that the wiring pack sent the first said that it fit all the 2017 toyota vans byt installer said that our van did not fit the first one, he gave me the item number that you sent last and that has been installed.
I love the looks and appears to be every thing i wanted in a hitch.
Works well. I ran it through the interior of the car instead of under the chassis. Since I don't have a lift; that was a better option.
Trailer has been my go-to and always am happy with your products, services and info you share. I rather buy from you than Amazon. Keep up your great products and service. Thanks!
Superb. I cannot imagine going elsewhere for hitches and accessories. Since I am not too handy I find the videos invaluable as a source of techniques and tips. The kit contained everything necessary for the installation except basic tools. The trailer lights worked first time so what more need be said. I needed the trailer in a hurry but I did not have a way to lift the van so I could only do a temporary job of running the hot lead forward to the battery, with the plan to have my regular auto mechanic redo it correctly asap. You will have to lift the van somehow to do a thorough job of securing that long lead. I wish I had bought dielectric grease, extra double sided tape and extra connectors.
Colin S.
10/6/2018
After one year it still works perfectly and I am fully satisfied. Great product and service from eTrailer.
The kit is perfect, came with everything I needed plus some. The only thing I did different was instead of running a new line back to the battery, I jumped off to the cigarette lighter right next to the rear compartment and put a 1 amp fuse on. My lights are LED so the draw is nothing. Saved a lot of time having to run that wire.
Justin
2/21/2024
It’s worked out great! It’s nice to be able to use the mini van for the smaller trailers. East install. I did not run the feed back to the battery. I installed a 3 amp fuse and went off the cigarette lighter port next to the tire jack. The trailer has LEDS and only used an amp.
Mike L.
2/21/2024
I installed the wiring myself on my Toyota sienna. I did not have a problem with any part of the installation. It took a while but at the same time I was working slowly to make sure I did it right and I was just enjoying working on my van, seeing the under side when running the wiring up to the front. I used an actually fishing pole and stuck it into a hole in the engine compartment to fish it up to my battery. I installed the little dude box right there next to my battery. I had more then enough length of wires which I don't understand why some people complained about it being too long. I actually had about 3 feet left. I ran it under my van and up through the engine compartment to my battery. I was not very confusing to clip to the clip to the appropriate clip on the lights because of the shape. Making sure which side is which was a little confusing but just paying attention to what you are doing will make that an easy job. I'm glad I did it myself.
Kurt Z.
3/30/2021
So far I havent had any problems at all. The fuse hasnt blown, the rain hasnt shorted it the circuit. They have worked everytime I hooked up the trailer. Its worked perfectly for me.
This is the second one of these I’ve purchased and installed. It’s a great kit except for two things:
1) the power wire that runs to the front is just barely long enough to get there. I think an extra 3-6 inches would be nice.
2) the sticky tape that holds the light unit to the chassis never works. A second self-tapping screw would be nice. I just used a zip tie to hold it in place.
Custom fit and well worth it.
Easy to install. I did not run a wire up to the battery/fuse block. I installed a cigarette plug on the wire and used the power point near the tailgate. I keep the cigarette plug and trailer plug wires in the jack storage area. I rarely use the trailer lights as my hitch is mostly used for bike racks and a hitch basket.
Shipping was fast.
Mike L.
9/5/2018
Drawing the power directly from the battery serves to isolate the tow vehicles sensitive electronics from any short circuits that might occur in the trailer wiring. Connecting the converters power feed anywhere other than the battery or where the converters manufacturer recommends can leave your vehicles electrical system exposed to possible damage, and will also unfortunately void any warranty coverage.
Got the wiring harness in the mail and got it installed the very same day. Easy to follow instructions and was designed for my vehicle. Was able to pick up the travel trailer the next day after installation.
Jim M.
12/17/2021
Been on several camping trips with our new trailer receiver hitch and wiring harness is installed on a Toyota Sienna and the 2 respond as 1 vehicle. Very satisfied.
2018 Toyota Sienna XLE. The wiring harness blows my fuse or other wise makes my turn signals not function properly; I've tried connecting them four times and they keep malfunctioning. So I have to keep them disconnected at the tail light assembly. The brake lights work fine.
Mike L.
10/12/2022
Is this occurring with a trailer plugged in? There could possibly be a short in your trailer wiring causing fuses to blow. Ill link to a troubleshooting article that will provide some direction for you. If this occurs when the trailer isnt plugged in, you might have a faulty harness that needs replacement. If thats the case, get back with us and well help further.
I installed the T-One wiring harness in a 2018 Toyota Sienna mini-van. The instructions were easy to follow and the connectors to the rear lights were exactly what was needed for the van. The extension that is pulled out to connect to the boat trailer worked as expected and I store it in the side rear wall cavity, which also houses the tire changing jack.
For installation, some reviews I read tapped into the wiring to one of the rear plug-in outlets. I was not comfortable doing that so I choose to run the wiring to the battery (in the front-mounted engine area) internally and well hidden under carpet and side panels. The biggest (and only) challenge was to penetrate through the "firewall" barrier between the engine compartment and the car's passenger side front seat area. Mission accomplished.
The function of the harness has worked flawlessly. If I ever install wiring to provide working running, brake, and turn signal lighting to a trailer, I certainly would return to etrailer.com.
The T-One Vehicle Wiring harness was easy to install. The video was very helpful, but it could use a description of how to run the power line up to the battery. I ran mine (2020 Toyota Sienna XLE) on the inside of the vehicle until I got to the fire wall then went out through a rubber grommet above the accelerator and brake pedal. I used a trim tool kit to move trim pieces enough to slip the wire under the trim.
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Gwendolyn Y.
4/7/2025
I looked up that sailboat and they look like a lot of fun, David! I can remember loving watching the Olympics and watching them race.