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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.
Route the 4-flat to the center of the vehicle. Secure the 4-flat to the center of the vehicle in a convenient,out of the way location or the rear hitch. Use the provided cable ties to secure any loose wires.
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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The kit fit well. Plenty of wire and connectors. The ground connector could have had a larger hole for where I located it. Installed and tested. It works well.
First of all, etrailer's delivery was very fast (even though I used USPS). This unit replaced an identical unit that was just over 2 1/2 years old. The old unit had internally shorted out. Since this is powered up all of the time (like the keyless entry and computer) I'm just pulling the fuse out when I'm not towing. Otherwise, the unit works great. I think vibration and road shocks may have damaged the original unit while it was powered up. For the new unit, in addition to the included double stick tape, I screwed the unit to the car's body. I'm also going to add a strap around the control box as well.
Very clever trailer lites wiring harness! Works great!
Very easy installation. Directions were excellent. Harness works great.
This kit worked great. I ran the wire into my trunk area so that the connector does not get corroded. I have used this to connect a trailer about 4x and have had no issues.
As advertised, no problems. Tutorials helpful. Etrailer solid people.
Have done quite a bit of business with etrailer and have never been dissapointed.
Well detailed instructions helped make the installation go very well. No troubles encountered.
Worked exactly as described for towing a trailer. However, when adding towed vehicle wiring to my 2020 Cherokee Trailhawk,to tow behind my motorhome, I discovered that this connector will backfeed into the towed vehicle wiring, causing improper light operation, when the vehicle was towed behind the motorhome. If you unhook the connector to the driver’s side taillight & rehook the factory connectors, the towed vehicle wiring then operates correctly. When needing to tow a trailer, I just rehook this unit’s connector to my driver’s side taillights, and then lights on the trailer operate properly.
Pretty easy to install. I would recommend, if you have to drop muffler to install your hitch, install your wiring BEFORE reattaching the muffler. Also the directions stated to fish the wires UP through the bumper to the tail light. My arm is not thin or long enough for this. I dropped a ratchet strap down through the bumper, hooked it to the wire and pulled it up. Super easy. The power wire I ran under the wheel wells behind the plastics. Same with the undercarriage. Removed some bolts for the plastics and tucked the wire. I mounted the connector to the hitch with a cheap zip tie bracket I also bought from this site.
Internal packaging held up well compared to the shipping box
Easy to install!!! Plug and play and installed in under an hour
Easy to install. Awesome how to guide. Works like it should
Easy to install and allowed my family to tow our belongings across the country ourselves and save a bunch of money
Gwendolyn Y.
3/28/2025
Moving is never easy so I could only imagine how it was to move across country! Hope you and your family have settled in nicely in the new home :)
The installation of the Curt T-Connector Vehicle Wiring Harness went pretty smoothly. The Installation Video was a great help; I just followed along step by step, and it ended up working perfectly! I would definitely recommend this product. Having a lift would be very beneficial and cut down the installation time immensely.
Developed a “short” somewhere causing the running lights to stay on constantly. Checked ground and wiring and still can’t trace it down.
Jenny N.
5/29/2023
There could be more than one reason why the trailer lights are staying on constantly, starting with a corroded connector. What corrosion does is cause a short which can lead to the lights staying on, and when you unplug the connectors, they would, of course, turn off. So, start by checking there, and if you cannot clean the corrosion, you can replace the connectors on either the side of your vehicle or trailer. The other possibility is a short caused by damaged wiring on the trailer itself that is causing the power to remain, so you will want to check your wiring carefully looking for any damaged wires and repair or replace as needed with 10-gauge wire part # 10-1-1. I have added a link below to a help article on a troubleshooting guide for you to take a look at.
Helpful Links
Gary
5/24/2024
Still having issues with the wiring. lights are not working, took to an expert and they say its in the harness box
plugged right in
Clear instructions, works perfectly
All good. Installation video was very helpful. Took about a 1 1/2 hour to install. Everything works perfectly.
I bought this and a trailer. From the start I had issues with the lights on the trailer. After taking it to an auto-electrician, he diagnosed the issue to be with the wiring harness. I followed up with etrailer and they were of excellent help in trying to figure out the issue. Ultimately they provided me with a replacement harness.
I received the harness but the issue persisted unfortunately. Eventually I was able to find the trailers wiring connections were all loose and got everything working. Throughout the process, etrailer was of great help and did their best to resolve the issue that wasn't even theirs. Installation videos are also excellent. Good job.
Brooke M.
4/23/2025
Kudos to you for sticking with it and not giving up! It's always a good idea to check the connections like you did :)
It is a complete add on towing light kit that was easy to install and it worked perfectly. The only somewhat difficult part of the install is running the power cable from front to back and that is only because of how low to the ground my car is. If I needed another kit I would buy the same kit from etrailer.
Followed the installation video and completed installation with ease. Great addition. All working and matches to factory rear lights. The install videos are amazing.
The wiring equipment works great even a year after it was installed. We tell everyone we know to buy it here with etrailer best equipment for heavy haul moving.
Only thing I would suggest is including more butt connectors and zip ties in the kit. It's nickel and dime stuff and you can easily mess up a butt connector and have to go purchase another. Cost is minimal, and the time to go to a local store for extras is a pain. But overall, great product.
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Charlie
9/7/2025
Still working