Oyviny 4‑Pin Trailer Wiring Harness for 2004–2007 Toyota Highlander — Direct‑Fit with Powered Converter

The Oyviny 56107 is a custom 4-pin trailer wiring harness engineered to add a factory-style 4-way connector to 2004–2007 Toyota Highlanders equipped with the factory tow package.

If you own a 2004, 2005, 2006 or 2007 Toyota Highlander with the factory tow package and want a reliable way to power trailer lights, this harness provides a direct-fit, plug-and-play solution. Built with 16 AWG pure copper conductors and a powered converter module, the kit maps your vehicle’s signals to standard 4-pin trailer wiring without splicing into factory circuits. Weather-resistant caps and a fused battery feed protect the system for long-term use while preserving the Highlander’s original wiring integrity.

How does this harness connect to my Highlander?

The Oyviny 56107 plugs into your Highlander’s existing tow-package connectors—no cutting or splicing required. It uses custom-fit plugs designed to match factory sockets and a powered module that draws directly from the battery to power trailer lights reliably.

• Direct-fit connectors for Highlander 2004–2007 factory tow package
• Powered converter module with battery feed to prevent vehicle circuit overload
• Simple unplug-and-insert installation, typically no tools beyond basic access

What lighting functions does the 4-pin connector support?

This 4-pin standard flat connector transmits taillights, turn signals and brake lights from the vehicle to the trailer. The included tail light converter conditions vehicle signals so the trailer receives proper, compatible outputs.

• Tail lights (running lights) transmission
• Left and right turn signal outputs
• Brake light feed shared with stop/turn circuits via the converter

Is the wiring durable and protected from the elements?

The harness uses reliable materials to withstand road conditions and seasonal exposure. Connectors are molded from durable ABS, wiring is 16 AWG bonded pure copper for solid conductivity, and rubber dust caps shield vulnerable points from moisture and dirt.

• ABS plastic connector housings resist impact and UV exposure
• 16 AWG pure copper wires for consistent electrical performance
• Rubber dust caps on connector and fuse to reduce corrosion and short risk

How long does installation take and do I need special tools?

Installation is designed to be quick for anyone comfortable accessing the rear tow harness on a Highlander. Because this is a plug-and-play kit that uses factory-style mating connectors, no splicing or advanced tools are required—most installations can be completed in under an hour.

• No wire cutting or splicing; fits into factory sockets
• Includes fused battery connection for safe power supply
• Typical install time: 30–60 minutes depending on access and experience

Who is this for? The Oyviny 56107 is aimed at owners of 2004–2007 Toyota Highlanders who have the factory tow package and need a dependable, OEM-friendly way to add a standard 4-way trailer connector. It’s ideal for commuters who tow small trailers, campers or cargo carriers and want a clean installation that protects the vehicle’s original wiring while delivering steady trailer lighting performance.