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Wiring up a trailer connection doesn’t have to mean cutting into factory wires. The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector plugs directly into existing factory plugs behind the tail lights. It’s a clean, plug-and-play setup that gives you a fully functional 4-way flat connector for running, turn, and brake lights without any wire splicing.
If you plan to add a brake controller or a 7-way connector later, this harness gets you started. Once the 4-way is installed, you can simply use an adapter such as part #37185 or the Universal Installation Kit part #ETBC7 to add those circuits. It’s the straightforward first step when you’re setting up for towing trailers with brakes or on-board batteries.
The built-in converter adapts vehicles with separate turn and stop signals to standard trailer wiring, combining them into a single two-wire system. That means it handles both incandescent and LED trailer lights correctly, maintaining the right resistance so signals operate as they should.
A pre-attached ring terminal makes grounding simple—just secure it to a clean metal surface. The included double-sided tape mounts the small black converter box neatly out of the way. Once connected, the harness stays protected from the elements, giving you reliable lighting every time you hitch up.

Customer Satisfaction Score:
97% were satisfied with this product
3% of customers were not satisfied
Ratings & Reviews

Chris
1/6/2022
Absolutely no issues with this harness at all. I am amazed at how many Dodge truck owners I have had this conversation with, where they bought and installed it with the same success.

Daniel M.
5/22/2021
A year later this harness fixed all the problems which seemed to be steming from human error in wiring. With this harness,I have not looked back.. Thank you..

Laura E.
6/1/2017
Dakoda, thanks for the reminder! Dielectric grease is available under our related parts tab found on the product page or individually as part # 11755.
Helpful Links

Harry P.
4/18/2017
it is a good product i recommend it

Rian M.
7/12/2014
Hi Bob H. Saved you a small fortune. Did you use this kit to bypass a problem with factory 7 pin connector? My left turnbrake on 7 pin is not working and Dodge dealer wants $1200 to replace power distribution center fuse box under hood. Thanks in advance for any help.


Bob H.
10/25/2014
This unit has been in regular use since I installed it about a year ago. I tow 8 to 10 thousand miles a year, and reliability is extremely important to me. Ive had exactly ZERO PROBLEMS with this system. Its an excellent product.
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Zach E.
9/13/2017
Still works great!