Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2018 Mini Cooper
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2018 Mini Cooper
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Wiring a trailer normally means diving into your vehicle’s wiring, but not with this harness. The Curt T-Connector plugs right into the existing tail light connectors to create a 4-way flat trailer connection. No wire cutting or splicing—just plug it in behind each tail light and it’s ready to power your trailer’s lighting signals.
The powered converter draws power directly from the battery instead of the vehicle’s lighting circuits. That keeps your factory wiring protected from overloads or shorts that might happen on the trailer side. It also ensures that your trailer lights get a consistent, full-power feed so they stay bright and dependable every time you tow.
This harness works great with standard bulbs or LED trailer lights, so you don’t have to worry about compatibility. The converter handles the difference in load so your signals stay in sync with your vehicle lights whether you’re running incandescent or low-draw LEDs.
Once installed, you get a standard 4-way flat connector that powers running lights, brake lights, and turn signals on your trailer. It’s the essential setup for small and mid-size trailers and can easily be expanded to a 7-way connection later using an adapter kit if you decide to add electric brakes or a charge line.
Customer Satisfaction Score:
96% were satisfied with this product
4% of customers were not satisfied
Ratings & Reviews
Mike L.
10/26/2025
There are a couple of good benefits of having the taillight converter being directly connected to the vehicle's battery. For one, it helps keep the tow vehicle's wiring system isolated from the wiring on the trailer. If a short circuit happens in the trailer wiring, the harness/converter will prevent the vehicle's wiring from being damaged. Secondly, the taillight wiring harnesses of most never vehicles aren't capable of handling the power requirements of both the vehicle and the trailer taillights. A direct power draw from the vehicle battery is very necessary. I hope that helps explain it for you....
Brooke M.
6/5/2025
I know you probably haven't installed it yet, but we would love to know what you think once you have, too :)
Michael
5/2/2023
Product is great. Not a single problem after over a year. I installed the 7500lb hitch with the above wiring harness. Figured to go a little over max tow capacity to ensure a great towing experience.
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Mike L.
2/22/2026
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