Curt T-Connector Vehicle Wiring Harness with 4-Way Flat Trailer Connector
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1979 Ford Van
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1979 Ford Van
Arrives before Christmas To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.
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Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.
Features:
Specs:
Installation
This custom-fit T-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.
Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location within your 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 tail light converter is built into this T-connector. This converter is a circuit-protected, battery-powered unit that bypasses the electrical routes that are used by a basic wiring harness. As a result, there is virtually no draw on your tail light circuits.
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 the trailer. This converter combines 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.
Curt builds each tail light converter using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability and durability.
Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? Curt converters also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.
Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.
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In the etrailer installation video, the installer states that you will need to splice in a segment of wire for the passenger (green) side for this kit.
Not being a fan of splicing in additional potential failure points, I tried to install this by not placing the module before running the wire, along with installing it BEFORE installing the hitch.
Doing the wiring FIRST made install considerably easier.
And in doing my process, I was able to fish the green wire across the back but ABOVE the rear bumper mount brackets which you would have very limited access to if you install the hitch first.
Doing it in this manner, the wire BARELY fits without splicing, so it can be done but Curt most certainly needs to add about 3"-6" of wiring to the green side in order for better fitment.
And running that wire up to the front for battery access is not the easiest, especially for an OCD person like me who does not like exposed wiring so yes I do disassemble trim on the vehicle to run the wire.
DIFFERENT WAY TO INSTALL CURT WIRING HARNESS on Kia Sportage
II just purchased a 2025 Kia Sportage Hybrid and ordered the Curt wiring harness for it. When it arrived I did not like what the instructions said, mounting the electric module outside under the car along with 4 pin plug for the trailer. I looked for ways to mount everything in the spare tire well and did it as follows.
First I added one foot of wire to the four wires that go to the drivers’ side light. (See Picture) In hind site you could do only three because the white ground wire been place in the spare tire well.
Second I removed the plastic piece where the rear hatch locks on to. The are two push pins to remove and just pull it up the black panel that runs across the bottom. I then removed the weather stripping from the light down to where the spare tire area is. I then cut a ½” slot in the piece of metal that the weather stripping slides onto near the light using a Dremel, I filed it smooth and wrapped electrical tap around the four wires where it went thru the slot to protect them. (See Picture) near the light. I then work the wire up from the spare tire compartment slipping the wire under the plastic to the slot and then behind the drivers side light. I then screwed in the ground wire. (See Picture) I plugged the two connectors in, and reinstalled the drivers side light See picture of driver side light reinstalled. Next I extended the green wire going to the passenger light by 1 foot. I ran the wire to the passenger side of the spare tire well. Next with my Dremel cut a small slot maybe 1/8” wide so the green wire would fit in it. Just like the drivers side I ran the wire up into the plastic which is covered by the weather stripping, thur the slot and then plugged the two connectors in and then reinstalled the light.
Last thing was to get the power wire installed to the electrical module in the spare tire well. I connected to the spot in the picture near where you jump the car.(hybrid does not have regular 12 battery) See Picture. I then ran wire along both of driver side of the car, zip tying it along the way. In the spare tire well there is a plug left of the spare tire I pulled out and used the end of my pointed testing light to poke and hole thru it. Look down where that plug was, you can see light, which is where there is a plug in the frame. I pulled that plug out, it already has a whole in it, ran wire thru it, and it was easy to get wire into hole in the spare tire compartment. I then push wire thru that plug and re-inserted plugs,both on the frame and in the tire well. Very good seal going thru the plug in tire well. (see pictures). I connected power well under the hood and then connected power wire to the black wire on the electric module.
I now test the output on the trailer plug and everything was good. I re-installed the plastic piece running across the back under where the hatch closes and I was done.
The electric module and the trailer plug are now inside the spare tire compartment, out of the weather, and all I have to do is lift the lid of the spare tire a little and let the plug hang down to the bumper and plug my trailer in.
The wiring harness is as advertised and a good quality. The real reason I give the purchase five stars is because of the company and the employees that worked with me, help me with my order and kept me informed every step of the way. It’s refreshing to actually good get good customer service.
In addition to the trailer hitch not having the mounting hardware (that I had to get myself and pay overnight shipping because they didn't have in stock) they sent the wrong harness for my vehicle even though I confirmed my VIN for assurance that I was getting the correct parts. When all is said and done, the cost will now exceed the price the dealer quoted for OEM parts. Epic fail.
I had the harness installed by an installer in your installer list, West Tire and Auto Repair. They did a good install. In an install video on your website it was found that the green wire going to the passenger side tail light was too short. It was for my install my install also. Etrailer needs to look into this.
Works fine but needs longer wires to make installation easier. Just barely enough wire so you can’t really secure it well with the zip ties.
Application said for 2024 kia sorento ex. But when I removed the tail lights connectors were not the same. I tested and spliced the wires to make it work. Works fine.
The wire harness looks easy to install. It is not. I had to remove all the rear cargo area covers and the leftside rear light fixtures only to determine that the part does not match the light connectors on myy 2025 Kia Sorento HEV. I am sending it back.
Gwendolyn Y.
11/25/2024
Hey Thomas. That doesn't sound like a pleasant experience. I do see you spoke to William and he's going to make sure you get a full refund on your order.
Hitch was easy to install. Wiring took some time but when done everything worked. Is
Installed on a 2024 Kia Sportage Hybrid.
The wires to the passenger taillight are way too short to make it easy. You have to get very crafty and get your arm in the cavity between the chassis and exterior bumper to make it work. Took me about 2 hours but eventually got it.
The video they provide is comical. You buy a kit, and a kit is usually everything you could possibly need to do the install with ease. The guy in the video then cuts the wires and adds more, uses shrink tubing, etc to get the kit to work. So even when they made the video they knew it wouldn’t work.
Plug and play so that was nicel, but if you have no experience or intuition working with your hands or a car, good luck, because you’ll need to spend way more money to get it to work if you have zero experience.
Simple fix to eTrailer, if you don’t want negative feedback on this product, extended the wires to a realistic length, it isn’t that hard.
this item would of worked but ended up sending back for the Factory lighting hook up because the factory one was plug n play much and easier for me to hook up. The factory one was more than triple the price but cleaner/professional install.
Awesome product worked well.
Would be a good idea to extend the wire to the passenger side. Then it would be 10/10
Solid wiring kit. Worked well and was relatively easy to install.
It’s working like it should
Great job Dalon! Excellent customer se rvice.
Easy install and a quality product!
It worked very well very pleased
The hitch is great and works fine, a great fit as well ,easy to install. The wiring leads could be a bit longer
great service very fast delivery
Installed on 2009 Honda Accord with V6. Piece of cake to install. I just use it for a bike rack that I already had. But note that I had an identical car with the 4 cylinder and I purchased the corresponding wiring harness and installed at the same time as a hitch on that vehicle as well, and I pulled a small trailer with a dirt bike for a couple of years. It worked out just fine. Never had any issues. High quality hitch and components. etrailer has always been really good to me.
Wire too short to reach the other side of tail light. Even though this is consider custom fit to my car, but I had to retrofit it to make it work.
Jenny N.
6/7/2024
To be honest, it is not the first time we have heard of this. The manufacturer is aware of it however has not yet added to the length. If you have any other questions about the harness please let me know.
The harness leads to the tail lights are just plain too short. Install is impossible, so I will be making a return.
Jenny N.
3/19/2024
I know that the harness for the 2023 Kia Optima is tricky to install with fish wiring the wiring through the tail lights. I took a look and I do not have a harness that would install differently. I do have a video install on a 2023 Kia Optima that can help. Please see the link below.
Wires are too short and it really makes installation a pain. Both "legs" of the wires that lead to the rear light assemblies of the car are not long enough, especially the single green wire going to the passenger side. But the driver's side is also about 6"short, or at least another 6" would make it easier to install.
Running the power wire to the battery was easier than I anticipated. The toughest part was getting it up from the ground into the engine compartment.
Finally, if you're going to have to splice wires that are exposed, provide heat shrink butt splices so you have a chance of eliminating water and corrosion.
When ordering the wiring harness I asked about installation. They told me it is a custom harness that just plugs in line with the vehicle brake lights. I received the harness and this is not the case. The rep that initially spoke to me about the harness clearly did not know what they were talking about. Still not that complicated but significantly more complicated than getting an OEM 4 pin connector kit.
Overall, I am satisfied with this wire system. It worked without a real problem. Please know that the instructions are vague and there’s still no videos out there that I have found for the 23’ Kia Sportage. The plug and play connectors are great and make the job easy. My only complaint is that the wires aren’t long enough. The left side connector doesn’t allow for the module to be mounted anywhere because the wires are too short and I’d doesn’t hang down far enough. As a result the flat trailer light connector is also a little short. It reaches only because I have a lot of wire connected to my camper. The right side taillight wires are again too short. It barely reached the taillight connection, it works, but the wire is stretched tight. Let’s hope it doesn’t break. They should really consider adding more wire to each connection. It took me 1.5 hours total. I ran the power wire inside the car under the kick plates to the engine compartment. I didn’t feel like crawling under the car to run it.
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Alan
10/17/2025
I ordered the wrong part and they fixed it for me. It was totally my mistake, and I contacted them, and explained my problem. I expected it to be a lot of problems to correct, but they simply sent the correct item and credited once I return the wrong one. I saw someone else say the same thing in these reviews that a wiring harness is pretty basic I would order from these people again because of the customer service