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Wiring a trailer usually means cutting into factory wires, but this Curt T-Connector Vehicle Wiring Harness skips all that. It plugs straight into existing connectors to give you a 4-pole flat trailer plug. No splicing or tracing wires—just snap it in and it’s ready to go.

The 4-flat connector covers the standard lighting functions—running lights, turn signals, and brake lights—so your trailer stays visible and legal on the road. It’s the most common setup for small and mid-size trailers and works seamlessly once connected.
This harness includes a powered converter that keeps your vehicle’s wiring safe from overload when powering trailer lights. The converter isolates the trailer circuit from the vehicle circuit, giving you steady performance and protecting sensitive factory electronics.
Not every vehicle comes wired for towing. This harness is designed specifically for models without a tow package, making it an easy way to add trailer lighting without modifying your vehicle. Plug in the connectors, run the power lead, and you’re good to tow.
This will not affect how the tail lights on your vehicle operate.
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hi everybody. Andy here with etrailer.com. And today, we're gonna take a look at this current T-connector vehicle wiring harness with four-pole flat trailer connector. Now this harness is designed to fit your 2022 Hyundai IONIQ 5. And this harness is going to give you a four-pole flat trailer connector at the back of your IONIQ to power your trailer signal lights. This is going to be compatible with five-pole, six-pole, and seven-pole adapters, and of course, those adapters are sold separately.
And this also includes this dust cap that is going to keep that four-pole flat connector clean. And so when you're not using this connector, you just need to secure that cap and that's going to be nice and clean for you the next time you're ready to use it. Now the black box that you see here on this harness is a powered taillight converter. And this is going to ensure that your vehicle's wiring matches out of your trailer. It connects directly to your vehicle's battery to avoid overloading your vehicle's electrical system, reducing the strain on your vehicle's wiring system.
By the way, Curt builds each kit converter box using surface mount technology for consistent reliable performance. It maximizes trailer light yield and intensity while producing minimal heat ensuring superior operation in rough road conditions. Now this harness is designed to connect quickly and easily. The connections with the yellow wires go to your driver side, and the connections with the green wires goes to your passenger side of your vehicle. And you will need to locate your vehicle's taillight wiring harness behind the driver side and passenger side taillights.
You're going to have to remove the hatch full of coverings under seat divider and side panels. Now once you locate the vehicle's taillight wiring connectors, then you're going to separate the taillight connectors and you wanna be careful not to break the locking tabs and you're going to insert the T-connector ends between the vehicle wiring connectors and lock them into place. These T-connectors are custom fit for your IONIQ so they're gonna match up perfectly with the connection points on your vehicle and they snap and lock together for a nice tight secure fit. Now once you have these plugged in, you are going to need to make a good ground connection. The ground wire is this white wire and as you can see here, it does have a ring terminal attached to it and it does come with a self-tapping screw.
So you can get this grounded to a suitable location such as your vehicle's frame or crossmember. You just wanna make sure that the surface is clean and rust-free. Next, you're going to want to mount this converter box to a safe, out-of-the-way location. You can do that with another mounting screw that you might have on hand or with this double-sided adhesive tape or with one of the mini cable ties that comes with this kit. Next, you are going to need to run the hot lead wire from the converter box to your IONIQ's battery. And again, that's this short black wire here that's coming out of the converter box. This short black wire gets connected to one end of this included bundle of black wire using one of the included butt connectors that you see here. Then the other end of this bundle is going to get routed to your vehicle's battery. And once you have this routed to your battery, you're going to take the fuse holder here and connect one of the wires, so you'll snip this in half and you'll connect one of the wires with the second butt connector to the routed wire. And then the other half of the fuse holder will get a ring terminal attached to it and that's going to connect to the positive post of your vehicle's battery. This does come with a 15-amp fuse and that's gonna go into the fuse holder and it has this cap to keep that fuse safe and protected. Now you can secure any excess or slack in your wiring with the included cable ties. And once the insulation is complete, this four-way connector will get mounted to the receiver tube. And I just wanted to make a recommendation for a mounting bracket, if you do not already have one. On your screen, I have our item number for a mounting bracket for a four-pole flat trailer connector and you can add that mounting bracket to your order and that's going to allow you to mount this connector nearby your trailer hitch receiver. You can just take that item number and put it in the search field of our website and it will take you to that bracket. Now the maximum amperage for the stop turn lights is 5.0 amps per circuit and for the taillights, 7.5 amps per circuit you are going to receive instructions to walk you through the installation process in more detail than what we covered today. And it is also recommended that you use a small amount of dielectric grease on all of your electrical connections like the plugs on the vehicle and the four-pole connector itself. It's designed to help prevent electrical failures caused by corrosion and moisture. So if you would like to pick that up as well, on your screen, I do have our item number for a tube of dielectric grease. And again, just put that number in our search field and it will take you to that item. Well, that's gonna conclude our brief look today. I do hope that it was helpful for you. Again, my name is Andy. Thank you for joining me.
Customer Satisfaction Score:
86% were satisfied with this product
14% of customers were not satisfied
Ratings & Reviews
Worked perfectly for my 2022 Ionic 5.
I had the wiring installed with the hitch installation. Everything seems to be working fine.
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