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Wiring a trailer harness doesn’t have to mean cutting into your vehicle’s wiring. The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector plugs right into factory connectors, so everything stays neat and reliable. It’s a true plug-and-lead design made for an easy DIY setup with no splicing required.
The integrated converter keeps the vehicle’s lighting signals working properly with the trailer lights. It balances the load between turn, brake, and running light circuits so your trailer lights operate cleanly every time you connect.
The 4-flat connector gives you all the essentials—running lights, turn signals, and brake lights. It’s the standard setup for small trailers, so once you plug in, your trailer lights will match your vehicle’s signals immediately.
The harness stays tucked away when not in use thanks to its hidden, vehicle-end connector design. You can route it cleanly through existing trim or grommets for a professional look that doesn’t leave wires hanging or exposed.
The harness includes clearly identified wire leads for each side. The yellow lead routes to the driver’s side and the green to the passenger’s side, so you always know which cable goes where during install. The shorter side is where the converter mounts for a solid fit and simple finish.
Ratings & Reviews
Pleasure to deal with this company.
Easy web site to use for order and arrived very quickly.
Perfect! Simple and fast.
easy to hook up using the instructions and the product working very well.
Excellent product.
Working perfectly, use once or twice a week.
Perfect fit. Works great. Easy to install.
Got it in, had this harness installed in my miata in less than 10 minutes, honestly it couldn’t have been easier, plug n play, no pics cause it’s hidden
Install yesterday, everything went well. Needed to buy a drill bit I didn't have but that was it. I chose not to drop the muffler, which only added about 30min. to the injstall.
Best price and fast shipping. Quality product.
eTrailer is one of the "Bench Mark" Online retailers.
Thanks to the photos, the instructions were simple. It was easy- peazy. Installation was "plug and play." It is installed in my 2006 MX-5 which I occasionally use to tow a small teardrop. This replaced a unit (same product) that was installed in 2011 which started failing intermittently. It lasted 9 years and 45,000 miles, I am OK with that.
The Miata trailer hitch is finally on. I was going to install it myself but decided that drilling the holes in the frame was not my cup of tea. So I took it to a garage that does that sort of thing and it is great. Fit perfect and looks great on the car. Love it...
Instructions and videos helped me to make the purchase and install. Removing the plastic covers in the trunk was easy since I learned where the connection points were. Absolutely no wires were exposed after install which made it look factory.
Never had any problems but traded the Miata in May 2020 for a bigger vehicle.
Didn't have one of these when I had a trailer hitch installed on my 2012 Mazda Miata MX-5 and decided to have one this time. The hitch will be installed later this week but I installed the wiring myself this time and it only took me about 20 minutes, which also included the reading of the instructions and dodging the raindrops because the little car was outside at the time.
Listed as a wiring kit for the 2016 Miata. According to my Miata mechanic the kit is a mismatch for the vehicle; for example, two connectors in the kit leading to a harness with six wires in. He refused to attempt an installation. Called etrailer product support, and their solution is to return the kit.
Had it installed, mechanic said no problems putting it on. Looks great.
Works very well.The connection was easy to do.
Very easy and quick to install, and works perfectly!
This was installed on a 2007 Miata. Very easy. Work well along with the hitch we put on to accommodate a bike rack. The bikes obscured the tail light and license. I made a strap on rack for stop and turn lights. The kit made for an easy, g reliable connection.
Fairly easy installation. Somewhat error-proof, as the plugs only go in the correct way, just be sure to follow the instructions and start on the passenger side.
Won't know how it works until my trailer gets here, but I'm confident it will be fine.
Bigote
8/13/2025
Super well. Pulls both my 2x5 box trailer and my 5x8 flat trailer with no issues.
It's great quality and works perfectly. I had to go from a 5 pole to the 4 pole. My left signal makes all lights flash. If you have a technician with a tip on how to correct this it would be greatly appreciated.
Lazer S.
3/24/2026
Glad to hear it's working well for you, Don! Well, mostly. Little odd that the left signal is causing all the lights to flash. First thing to check is your ground. Make sure it has a good clean connection and it isn't stacked with other ground sources (this is a common practice that I really don't like). If that's good, was the 5th port on the trailer for reverse lockout or something else?
I received the hitch unpacked it. Very nice hitch, etrailer sent me a list of installers also sending the local installers my name and email and text number the first one text me wanted $250 to install it. He ran a mobile installation truck. I asked him if he viewed the the video on installing it on my Miata MK five I told him I would contact him when it came then it came and you said it would take three weeks before you could get there and you’d have to install it in my driveway. I don’t have a driveway. I haven’t heard from him yet so I called RV something I don’t know their name they wanted $780 to install it something like $200 an hour 3 1/2 hours $780 wow then a third had contact me and I missed the call. I called him back was a really nice facility. They had plenty of parts for trucks and trailers and all kinds of commercial vehicles so I’m happy camper well almost I still have to buy the trailer turn it into a camper hauler and pull up behind my Mazda Miata, but I’m very happy with a hitch and I’m very happy with the service they provide in helping me to find an installer that was a really nice touch and the installer turned out to be a very good company so if you’re installing a hitch in the Sacramento, California area E trailer will probably give you their name and address. I believe they’re very good company. I probably won’t buy another hitch cause I’m very old and this is my last car but I give them five stars for the hitch and for the services they provide I swear well sometimes I swear on some kind of a book and I’m a human being and this is the honest truth that I believe each trailer is a very good company to deal with and when buying a hitch for your automobile or truck
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Gwendolyn Y.
7/25/2025
Can’t wait to hear how everything goes, what’s the arrival date for the trailer?