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Wiring a trailer usually means cutting into factory wires, but this harness skips that. The Curt T-Connector plugs right into the existing tail light connectors to give you a 4-flat trailer plug. The powered converter takes its signal from the tail lights but draws power directly from the vehicle battery, so the trailer lights don’t overload the vehicle circuits. It’s a clean install with plug-in connections and a dedicated power wire for reliable output.
Many vehicles can’t handle extra load on their tail light wiring. This harness avoids that problem by pulling power straight from the battery while using the tail light circuits only for signal. That setup prevents shorts or heavy current draw from damaging sensitive electronics and keeps everything protected. The power wire must be run to the battery to maintain full circuit protection and warranty coverage.
Whether your trailer uses LEDs or standard bulbs, this harness has enough output to keep them shining bright. It delivers 3 amps per circuit for stop and turn lights and 6 amps per circuit for tail lights. Because LEDs draw less current, there’s room to add extra fixtures if needed without overloading the system.
With its 4-pole flat connector, this harness provides all the basics—running lights, turn signals, and brake lights—ready for most small to mid-size trailers. It’s also easy to expand later with an adapter if you need a 5-way or 7-way plug for more advanced setups like brake controllers or reverse lockout solenoids.
Good grounding is key for trailer wiring, and this harness includes a white ground wire that must be attached to bare metal free of paint, dirt, or corrosion. A proper ground helps prevent signal loss or flickering lights so everything functions consistently once connected.
Do not connect the power wire to a 12-volt accessory outlet; doing so can overload the circuit and void the harness warranty. Power must be drawn directly from the vehicle’s battery to maintain circuit protection and ensure proper functionality.
Customer Satisfaction Score:
95% were satisfied with this product
5% of customers were not satisfied
Ratings & Reviews
John S.
3/24/2018
Still very pleased with hitch and wiring kit a year later.
Dan M.
9/9/2014
No problems using it and I like that it stores inside the vehicle when not in use, which is most of the time.
Dan
1/19/2018
Easy hook up, very dependable.Thank you for a good product for my Daughters Mazda 3.
Bob K.
10/19/2018
After contacting Curt, they sent a new harness. It has worked perfectly ever since. I’m completely happy with the kit.
Bruce
4/20/2019
Great
Greg
5/9/2022
Excellent
Dan S.
7/27/2016
Yes still have all of the items, working awsome. Saved us a few hundred bucks installing ourselves. Will definitely order again on our next vehicle.
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Pascal
10/11/2026
Still great.