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Adding trailer lighting shouldn’t mean cutting up factory wires. The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector plugs inline with the existing taillight connectors, creating a clean, worry-free hookup. Each side connects behind the tail lights so you get power for turn, brake, and running lights without altering the original wiring.
Some harnesses struggle to send a strong signal to your trailer lights, especially on newer vehicles. This setup fixes that by using a dedicated 12-volt power wire that runs straight to the battery. The battery feed powers the built-in converter so your trailer lights get steady current without pulling power from sensitive vehicle circuits.
Once it’s plugged in, the converter box mounts inside the vehicle where it’s protected from water and road debris. The 4-flat connector can be routed out near the hitch when you need to tow, then tucked away when you don’t. It looks tidy and keeps all wiring safe from the elements.
If you plan to tow trailers with brakes or need a charge line later on, this 4-way harness is the first step. It pairs directly with universal 7-way upgrade kits like the #ETBC7, making it simple to expand your setup for brake controllers or additional trailer functions down the road.

Customer Satisfaction Score:
93% were satisfied with this product
7% of customers were not satisfied
Ratings & Reviews

Mark
5/23/2026
Works very well. No problems

Mark
4/29/2026
Perfect!


Gwendolyn Y.
3/13/2025
Hey Brande! I'm glad Ashley was there to help find the right parts and that the install went so smoothly! We will always be here and ready to help when you need us next :)
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Michele
7/30/2025
A year later- still works as expected!! No issues! Highly recommended over going to the dealership.