Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
This item does not fit your vehicle
2027 Volvo XC60
These items fit your vehicle
2027 Volvo XC60
To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.
Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.
Error submitting comment. Please try again momentarily.
This harness makes wiring simple. It plugs right into the vehicle’s existing connectors, so there’s no need to cut or splice any wires. Once the panels are pulled back, the T-connectors snap in place and you’re ready to go. It’s a clean, OEM-style install that looks factory once finished.
The included powered converter keeps the vehicle’s electrical system safe by isolating the trailer lights from the main wiring. It prevents overloads and interference, which is especially important when using trailers with multiple or LED lights. That means your signals stay bright and reliable every time you tow.
The 4-pole flat connector delivers all the basic lighting functions—running lights, brake lights, and turn signals—so your trailer is road-ready. It’s the standard connection for small and medium trailers and works with adapters when you need to upgrade to a 7-way setup later on.
Grounding the harness is straightforward thanks to flexible mounting choices. You can use an existing factory ground point, a weld nut with an M6x1.0 bolt, or the included self-tapping screw if no factory option is available. Each method ensures a solid ground for reliable light function.
This custom-fit T-connector plugs into your vehicle's wiring harness, which is located behind the driver's-side interior trim panel in your rear cargo area. Once you've plugged in the T-connector, insert the included 10-amp fuse into the integrated fuse holder. Then install the 30-amp cartridge fuse and two 7.5-amp mini fuses in the rear fuse panel.
Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location within your cargo area.
It is recommended that you use a small amount of grease on all electrical connections - the plug on your automobile and the 4-pole connector itself - to help prevent corrosion.
A tail light converter is built into this T-connector. This converter is a circuit-protected, battery-powered unit that bypasses the electrical routes that are used by a basic wiring harness. As a result, there is virtually no draw on your tail light circuits.
Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your vehicle's three-wire system need to be combined so they are compatible with the wiring system of the trailer. This converter combines the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights.
This will not affect how the tail lights on your vehicle operate.
Curt builds each tail light converter using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability and durability.
Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? Curt converters also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.
Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.
Customer Satisfaction Score:
98% were satisfied with this product
2% of customers were not satisfied
Ratings & Reviews
Kate F.
11/19/2025
Glad to hear we are doing things right Mungo! One of the reasons I love working here is that we do have real humans ready to walk beside you every step of your ordering journey. Why is this so rare now a days? What do you mainly haul around using the wiring?
Nick S.
9/22/2025
I'm glad the install went smoothly, that's what sons are for! The 4 flat tester is definitely helpful to have on hand. What are you planning to tow?
Do you have a question about this Custom Fit Vehicle Wiring?
Info for this part was:
At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.
John
2/17/2026
I have had no problems. Installation was less time less than 30 minutes than previous installations.