This trailer wiring guide comes complete with a color coded trailer wiring diagram for each plug type, including a 7 pin trailer wiring diagram, this guide walks through various trailer wiring installation solution, including custom wiring, splice-in wiring and replacement wiring. If your vehicle is not equipped with a working trailer wiring harness, there are a number of different solutions.. This is how to wire up a 7 pin and 4 pin connector on a Toyota Tacoma. If you are looking to make your vehicle look OEM, then this is the way to do it right.
1. Feed your Yellow wire through the factory 4pin harness loom. This serves to protect the wire. **optional, it's kind of a pain but it looks better. 2. Install the factory 4 pin harness. We will use the factory 4pin harness that Toyota sells, because why not use what they make available! 4pin installation instructions 2005-2010: 08921-04960.pdf. Toyota 4Runner Installing Trailer Wiring Harness How to Install Trailer Wiring Harness Use your 4Runner to its full potential. This article applies to the Toyota 4Runner (1996-2002). It is an amazing thing that.