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Wiring for a trailer usually means hacking into factory wires, but this harness skips all that. The Curt T-Connector plugs directly into the existing taillight wiring to give you a 4-flat trailer connector. There’s no splicing or tracing wires—just plug it in behind the rear lights and you’re ready to go.
Instead of pulling from the taillight circuit, this harness runs a dedicated power wire to the battery. That isolates the vehicle’s sensitive electronics and keeps your trailer lighting from overloading factory wiring. The converter box does the work of combining and regulating the turn, brake, and running signals so everything stays protected.
Once installed, you get a standard 4-flat connector that powers your trailer’s running lights, turn signals, and brake lights. It’s the common setup for most small and mid-size trailers, making it easy to hook up and go without extra adapters.
The harness can be kept inside the cargo area when you’re not towing. That keeps the terminals clean and safe from road grime or corrosion. When you need it, just pull the 4-flat out through the rear door seal—the thick weatherstrip cushions it when closed so nothing gets pinched or damaged.
If you ever need electric brakes or a 12-volt charge line, this 4-way serves as the foundation for adding a 7-way connector using an adapter kit like the ETBC7L. It’s a simple way to expand your towing setup later without redoing your wiring.
Customer Satisfaction Score:
95% were satisfied with this product
5% of customers were not satisfied
Ratings & Reviews

Victoria H.
1/24/2025
That does not sound fun Gary. I'm so glad this wiring harness fit your needs, and turned your experience around for you!

Gary
1/25/2026
Its has been a year and it is still performing perfectly.


Richg
10/1/2018
Nice of you guys to follow up. I was glad to write the review since I was well satisfied with the product and process. The hitch and harness have performed flawlessly. Your company will always be my first stop for anything tow related.

Brian M.
4/4/2018
They are doing fine and holding up well..satisfied. Thanks for checking.

Chris
3/12/2018
The T-Connector works beautifully. Installed easily and quickly. Ive wired many vehicles for towing and this is the way to go!!
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Evrett
8/24/2026
Still going strong! No regrets!