Trailer Wiring Harness Installation - 2017 Kia Sorento How to Install a Trailer Wiring Harness on a 2017 Kia Sorento. Today, in our 2017 Kia Sorento, we'll be having a look at and installing the Curt T connector vehicle wiring harness for factory tow package vehicles with a four pole flat trailer connector; part number C56151. 2017 Kia Sorento OE Wiring Harnesses & Stereo Adapters Kia Sorento 2017, Aftermarket Radio Wiring Harness by Metra®, with OEM Plug. For aftermarket stereo. Metra preassembled wiring harnesses can make your car stereo installation seamless, or at least a lot simpler.