To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.
Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.
Error submitting comment. Please try again momentarily.
Adding trailer lighting doesn’t have to mean chasing wires or cutting into factory harnesses. The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector simply plugs into your vehicle’s existing wiring, giving you a clean, plug-and-play setup. It’s designed for vehicles without a tow package and includes a powered converter so the trailer lights run off a direct battery feed instead of pulling power from the vehicle circuits.
With its built-in powered converter, this harness draws power straight from the battery to operate the trailer lights. That means steady, dependable current for running lights, turn signals, and brake lights—even when towing a fully loaded trailer. The converter isolates the vehicle wiring from the trailer load to prevent shorts or overloads that could damage the factory lighting system.
Starting with a solid 4-way connection makes it simple to add more capability later. This harness gives you a standard 4-flat plug that handles all the basic lighting functions and can be converted to a 7-way using an adapter like part #37185 or part #ETBC7. That makes it ready for brake controllers or trailer charging circuits when you need them.
Once installed, the wiring tucks neatly out of view thanks to its hidden plug-in layout. The leads route through existing spaces so there’s no need for drilling or exposed wires hanging below the vehicle. The finished look stays clean, while the weather-resistant connectors protect your signals from moisture and corrosion over time.
Customer Satisfaction Score:
98% were satisfied with this product
2% of customers were not satisfied
Ratings & Reviews
ALL WAS GOOD, WITH THE HITCH. THE ONLY ISSUE WAS THE EXHAUST ACCESS--HAD TO CUT AND FIT EXHAUST UNDER/BEHIND
Simple with good instructions. The way it should be! Nice work!
Worked perfect. Pretty easy install. Neat to have these t connectors for correct connection.
A true plug and play nobproblem on theninstall part worked perfect
Order came quickly and the part was correct. Staff at etrailers kept me informed by email concerning the status of the order
Worked well for the first 6 months. The installation was plug and play, very easy.
After that it stopped working for some reason. The electronics are sealed for water protection so no way to troubleshoot. Ended up ordering another one. Happy with it overall but I may just have gotten a bad one
The wiring was simple to install. I took a little extra time to put wiring loom over all the wires and routed them along the vehicle harnesses to protect them from damage. I haven't had any issues with the system and would buy again if I had to install another hitch.
Very easy installation. Great customer support
Easy install for mechanically inclined individuals. Everything worked great
Easy to install. Instructional video was very helpful. Reasonable price.
Installed easy and worked great!!
It works great for my 2023 Promaster van that did not have a factory trailer package
Well made. Seems like a quality item. Works for me.
Seem like a lot of wearing, but got it done. It worked great.
Very easy to install! Ask the parts needed were provided, thanks!
Easy install. Wires are just the right length.
Just what I needed.
Very easy to install again that video was very helpful. Highly recommend.
Very easy DIY project to do very explanatory on the website on how to do it.
Good product, thank you e trailer for the prompt delivery
Plug and play with easy picture instruc tions.
Install went smooth. everything was plug and play.
Fit my 2026 Ram Promaster perfectly. Video installation guides are super helpful.
Do you have a question about this Custom Fit Vehicle Wiring?
Info for this part was:
At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.
Uglyvan
10/15/2024
All went well with install and still working great.