Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2027 Subaru Ascent
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2027 Subaru Ascent
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Wiring a trailer can be tricky, but this Curt T-Connector makes it simple. It plugs directly into existing tail light connectors, so there’s no need to cut or splice factory wiring. The plug-and-play setup gives you a 4-flat trailer connector ready for basic towing functions—running lights, turn signals, and brake lights.
Some vehicles can’t handle the extra draw from trailer lights. This harness uses a powered converter that connects directly to the battery, keeping the vehicle’s electrical system isolated from the trailer. That design prevents overloading sensitive circuits and ensures reliable lighting every time you tow.
The built-in 4-pole flat connector is the standard hookup for most light-duty trailers. It provides the three essential lighting functions—turn, brake, and tail lights—plus a ground wire for consistent signal return. With solid terminals and weather-resistant construction, it’s built for long-term use on the road.
This hidden plug-in harness tucks neatly behind interior trim and along factory grommets for a clean install. Once in place, only the 4-flat plug is visible when you need it. When not in use, it stays out of sight, keeping the look of the vehicle clean and uncluttered.
If your vehicle didn’t come equipped with trailer wiring, this harness fills that gap. The included power lead and connectors provide everything needed to run independent trailer lighting safely—no factory tow package required. It’s a straightforward way to get full towing function without modifying your vehicle’s wiring system.
Customer Satisfaction Score:
92% were satisfied with this product
8% of customers were not satisfied
Ratings & Reviews
Easy install
I brought this to the ford dealer and had them do it in a jiff! saved a lot with already having what I needed.
Great product, it's worked well for me for a year.
With some help from a friend we installed this in 15 minutes, on my 2013 Ford Focus St. All cables and connections have held up well for the year I’ve had it, and I’ve used it a lot. I would recommend this product.
Easy to install works well
Everything was as advertised. The instructions were easy to follow and all went well.
All works just like it should. Good job
just got it and have not installed it yet, however the kit looks really good and im hoping it works as good as it looks.
Exact fit, all attaching hardware, good instructions, works perfectly!
Easy install if you ever done car wiring. As simple as wiring subs. Didn’t enjoy popping the taillights out but worth it.
hooked up easily and worked just fine.
Easy installation, with one exception. To correctly run the wires from the control relay to the light assembly without running them directly beside the rubber - which puts wire on sharp edge steel, instead of through the grommet, I cut the wires, ran them through the grommet and spliced together. This is much better. Curt mfg. should install inline connectors to make this easier.
The wire harness made it simple to put a trailer connector on my focus and works great for when I need to tow a trailer. I would highly recommend this product.
Fantastic service! Quality product, and easy to follow instructions. The installation video really is informative and we'll done. Everything still working great after 1 year. I got a perfect fit,too! The plug end curls perfectly around the hitch and tucks inside it, underneath the car, staying in place and hidden out of sight until needed. A++
Easy to install. Could have a better way of getting the inline plugs through the existing grommet easier, i.e. having quick connects so there is no need to cut the grommet. Other then that it was fairly simple to install barring the vehicles interior panels. The pigtail hides nicely under the drivers side rear window where there is an existing hole for access to one of the wing nuts for the tail light.
Everything is still working as it should...
It doesn't matter if it's our Kayak trailer or our small utility trailer the lights always work like the should.
Good easy to follow directions and a reasonably simple install.
Definitely would recommend!
Black box has something shorting out in it . Trailer lights worked good at first went to Minneapolis and back I problems . One day I come out and my right turn signal on my car is on . I had to unplug the fuse from the power wire to have my turn signals work normal . Hasn't worked right ever since
Plugs into factory wiring harness for the car with no issues, everything works great still after a year of use multiple times a month. Perfect for adapting my car to towing a motorcycle trailer.
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William J.
12/31/2014
All of the products are working as advertised. Had no problems with installation and they all are still working perfectly! Thanks for having such great products and such great prices!Happy New Year !!!!