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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 beneath your vehicle, near the trailer hitch. A mounting bracket (sold separately) is recommended to keep the connector secure.
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.
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Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Today on our 2018 Ford Transit T250 we're going to be taking a look at and I'm going to show you how to install the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. This is what our wiring looks like when it's installed. It's going to give us all the proper lighting functions to safely tow our trailer. It's going to give us both turn signals, our running lights, and our brake lights. It's going to have an added dust cap to help keep any dirt and debris from getting in our connections. And when not in use, it can double as a holder to help our wiring from dragging.
We're going to have 2.1 amps per circuit for our stop and turn signal and 3.75 amps per circuit for our tail lights.As far as the installation goes, it's pretty simple. You're going to hook directly into your factory wiring behind your tail lights, run your power wire up to the front of the vehicle, and connect it to the positive side of the battery. The nice thing about this wiring is it's going to have a modular box. And what that modular box does is it protects your factory wiring from any back feed from the trailer if the trailer has a wiring issue and vice versa. Now that we've gone over some of the features, let me show you how to get it installed.First thing we're going to do to start our installation, we're going to remove both tail lights.
T20 Torx bit. We're going to have a screw here, and a screw on the bottom. If you don't have a Torx bit, you can also use a flat head screwdriver. Once you remove your bolts, simply going to pull our tail light straight back. I'm going to go ahead and disconnect our wiring.
There's going to be a black tab right here. We're going to push down and pull out. We're going to repeat that process for the other side. Now we're going to take our wiring harness. We're going to take the yellow and we're going to feed it up from underneath and right behind our bumper through here.
The problem is I don't know if I'm going to be able to get this through this hole. What I'm going to do is I'm going to take out a couple of these screws right here on the corner of my bumper to give me a little extra space.And then I'll come up right behind this piece. It's good to add a little bit of dielectric grease before you make your connection. This is going to help prevent any moisture build up and corrosion. Plug that in there. Then we can reinstall our tail light. You can see how the wiring is hitting the back back here. I think what we're going to have to do, we're going to pop this clip off. Pull this off first. Maybe spin that like that and see if we can get it to work like that. Keep it in place. And we'll reinstall our screws. Now as far as my modular box, there's a couple ways you can mount it. It comes with two-sided tape. You can tape it here if you want. Sometimes that tape doesn't last. If that falls off, it's just going to be hanging. What I'm going to do is I'm going to slide it up like this to kind of help keep it out of the weather, and this existing hole, I'm going zip tie right through this hole into this one.Just go right through both of them. I'm going to zip tie it to that metal to help keep it tight. Then we don't have to worry about it falling. As far as my ground wire, I'm going to use a self-tapping screw that comes in the kit, 1/4" socket, and I'm going to go right through this metal. You want to make sure that your ground wire is on metal and not on plastic. Once you get your box mounted, your ground wire in, you're going take your 4-pole wire and your green wire go up over top of the frame rail. You can see I've got it right along inside of the hitch. I've bundled my 4-pole wire up here. Took a couple of longer zip ties, zip tied it around the bitch here to hold it in place. Got my 4-pole wire here. Green wire, ran it across, zip tied it on this side, over the top of the frame rail. Now I can run it up to my passenger's side and tail light.While we're here, we're going to take the black wire coming off our modular box. We're going to put a butt connector on it. The butt connectors that come in your kit, I suggest exchanging them for heat shrink butt connectors. These are just 10 to 12 gauge heat shrink butt connectors. If you don't have any, you can find some here at etrailer.com. A butt connector on one side there. We're going to take the black wire that comes in our kit and strip it back, add it into the other end just like that. And we'll take a heat source and we'll heat that up. I'm going to be using a heat gun. If you don't have a heat gun, you can also find those here at etrailer.com. Now we're going to run our black wire to the front of the vehicle. I'm going to get it done real quick and I'll show you how I did it.I went over my frame rail here, over my hitch, right along this, zip tied it here, followed this existing wiring because it runs all the way up to the front of the vehicle and just zip tied it along the way. Here, here, right behind my fuel tank support rods here, zip tie here, right up along the inside of the frame rail, there's a hard line right here, zip tied right there. And then we'll run it straight up the firewall to the battery. You need to get your black wire up to your engine compartment, to the positive side of the battery or positive connection. You can use an air line tube, which is what I used. A piece of wire works, too, to feed it down. This is pretty open here, a piece of string with a nut on the end of it, just something with weight that you can drop down in there. Get it pulled up. Make sure you stay away from anything hot or moving up in here.This is where I'm going to be connecting it. I ran it right behind my hard line. I'm going to zip tie it right there. I'm going to cut it off here. And then we'll add our fuse holder on. This is what your fuse holder's going to look like when you get it. Go ahead and cut it in half. Going to strip the ends, both sides. I'm going to add a ring terminal on one and then another heat shrink butt connector in the other. Now I think what I'm going to do instead of arriving us right here I'm going to go around this way. That way if I've got to heat shrink, when I shrink that up, I'm not heating up any of this plastic here. This will give me plenty of room to drop this over this way. Then we'll take our heat source and shrink that up. And then we'll just add it onto the positive terminal. We want to make sure when you do that connection our fuse is not in the holder. We want a direct connection.What I'm going to do . Let's see if I can't get this ring terminal so that we can close this. Now that we've made the connection, we can go ahead and add our fuse. Now we'll test out our wiring using part number I26. Left turn, right turn, brake lights, running lights. That'll do it for a look at and installation of the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector on our 2018 Ford Transit T250.
Average Customer Rating: 4.8 out of 5 stars (189 Customer Reviews)
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.Lighting kit was very easy to install. I watched the video first, which was very helpful.
Worked great and easy to install for the most part. Running the power wire is the hardest part having to squirm under the transit do often. Lol I did change one thing from the install vid for my 2016 Transit. I connected the power wire to the second terminal so I didn’t have to modify the cover like the video suggests. It just unclips front and back and then snaps back on. See pix.
Couldn’t get any simpler. I am very pleased with the quality of the product. It arrived as expected with all the items. I watched the installation video and went to work. It took approximately 1hr of crawling under the van but it’s well worth it. Only thing I’m missing is the bracket that mounts the 4way to the hitch. I’ll purchase that and be ready to roll!
Everything was as you advertised. Everything went so smooth even the one armed man could do it in his driveway. Both the trailer hitch and the wiring was great. I am going to do camping and am turning the back of my van into a RV. Will be planning on pulling a utility trailer for all my extra needs. The hitch I chose is a little over kill. But better safe than sorry.
Johnny
4/3/2020
GREAT!
Good kit. Good instructions. Pretty straight forward install. Only problem: the wire that must be run all the way to the engine compartment for battery power was about a foot or two too short! I wouldn’t buy again just for this reason. What a hassle to have to splice in addition wire and heat shrink. Otherwise works fine.
Jenny N.
7/14/2022
Running the power wire to the battery can be challenging depending on the vehicle. We do have a FAQ that can help. Please see the link below.
Helpful Links
Easy plug n play wiring harness with 4 pole connector. Wires were sufficiently long enough to properly secure along the vehicle frame. Kit comes with zip ties to hold and hide wires. We tapped the ground wire to a tie down bolt to the frame and ran the positive wire to the battery. This was a fairly easy install on our 2018 Transit.
King
8/28/2019
Great! We use it to haul our trailer every weekend.
Everything was delivered fast and top quality. The installation was straight forward and fun. Thanks.
Product arrived quickly and met specifications as advertised.
I have had to install several hitches for two of my ford transit vans they don’t come with tow packages. I purchased the electrical connectors and hitches from E-trailer and was able to wire up my Vehicles. they had the right part with easy video instructions great company highly recommend E-trailer.
The hitch fit as expected, but two holes needed to be tapped in order for the hitch to fit correctly. The wiring harness suggested worked as it should. I am happy with the hitch so far. My only hesitation from 5/5 stars was having to do additional tapping to get it to fit my vehicle. Luckily I had the necessary tools on hand.
Very helpful ordering service. Lots of knowledge. Ford required $260.00 for a flat 4 wire trailer module harness, E-trailer price was around $50.00 including freight. Shipping time was fast.
Frank
2/16/2020
tremendous
Easy install on my Ford Transit 250, the video was very helpful.
I would recommend getting 18 feet of conduit to route the wires under the van (12 volt black), under the bumper, and in between the doors.
running the wire under the van was the most difficult part (only because I had to crawl under the van), but there is easy routing all along the left(driver's side) frame rail into the engine compartment.
Tony M.
7/5/2016
Still going strong, I have taken my van down some nasty forest roads in AK and AZ and nothing has come undone after the washboards, potholes, mud and rocks!
Everything fit well and was going just as the installation video showed until I got the power cable to the motor (from underneath the van) and realized it was no where near long enough for my 148WB. Needed at least another 5'. Ended up having to remove the drivers taillight again and fished the cable inside the van from there and ran it right to the battery under the seat.
Sierra K.
7/22/2021
Thank you for your review. The wiring has to be installed exactly as the instructions say or there will not be enough wire. Extra wire purchased will have to be cut and spliced in.
No problems at all!
No problems with the wiring harness. All the connectors matched with plenty of wire for service loop.
Easy to install. Videos were great.
This was exactly what I needed for my full size transit van - Fairly easy install, but needed the power line to be about 3feet longer. Easiest way would be to put on a lift, but local garage did not have enough height to lift, so crawled my way under & attached power line with rubber tubing on every possible rub line. I may have woven the power line through too many attachment points, but never wanted to go back under to fix. I ended up about 2 feet short of my power source at the front, but heat shrunk a attachment to additional wire of same gauge and it works fine. Very pleased with purchase - 4 star due to short wire on the power side, but everything else was simple plug in - routed wires under he back sill plate for clean installation. Oh, suggest you have lots of wire ties available before starting this project.
The wiring installation went smoothly. After 1 year the wire we installed from the front of the vehicle rusted off where we connected it to etrailer's wiring at the rear. That was because we failed to wrap it with electrical tape. etrailer's wiring continues to work well.
I had a what I would call a sending unit bad with first wiring harness. I talked to two people on the help line. Nothing they suggested helped. A man from technical support called. He had several questions and then diagnosed the problem over the telephone. They immediately sent a new harness. All three people I talked to were very nice, couldn't ask for better service. Trailer hitch and wiring harness all working great.
Videos included with trailer hitch and wiring setup were spot on. I installed trailer hitch in 30 minutes. Wiring took 1 1/2 hours. I recommend you purchase the wire tester if installing by yourself. Well worth the few bucks to make sure all lights, tail and stop are working. Plan on purchasing super springs next.
Love it. Having the video online saved my bacon. Not normally comfortable with this stuff but I just followed the video you provided online and everything fit and connected up. I love when things work out. Will definitely buy from Etrailer again.
Jed
8/16/2019
Works like a charm. I’m not a mechanic but this just took a little time and came with clear video instructions specific to my vehicle. Trailer my boat and I would highly recommend this to anyone looking for plug and play trailer lights.
Although, I have not had time to install the hitch and wiring harness, your company provided excellent service.
disappointed, wire provided to connect to battery was too short, requiring a splice, followed the suggested route still 12"-18" short
Heather A.
2/25/2021
Thank you for your review. This is the first time we have heard of this issue with this particular wiring harness. It is important to follow the frame rail under the vehicle to the firewall and through to the engine compartment. I have the install video that shows the black wire being installed at the 4:55 time stamp.
Have owned this kit for a little over a year and haven't had one problem. Installation wasn't very difficult. Running the wire to the front to get power to the unit wasn't a lot of fun but, other than that, everything fit as it should.
I am looking at purchasing a brake controller for the camper I purchased. I will most likely look to etrailer for it as well.
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Ray
9/5/2021
I havent used it a lot, but dont expect any disappointments from it.