Oyviny 4-Pin Trailer Wiring Harness for Toyota Highlander & Lexus RX 2008–2021 — Pure Copper, Plug-and-Play

The Oyviny 56217 4-pin trailer wiring harness is a direct-fit, plug-and-play wiring kit that adds reliable trailer light connections to 2008–2019 Toyota Highlander and 2020–2021 Lexus RX 350/350L models without a factory tow package.

If your Highlander or compatible Lexus lacks a factory tow package, this harness supplies a safe, OEM-style interface for trailer taillights, turn signals and brake lights. It uses pure copper conductors and an ABS housing to deliver solid conductivity and mechanical protection while keeping installation straightforward—no cutting or splicing required. The kit also includes a taillight converter and inline fuse protection with rubber dust covers to reduce exposure to moisture and debris.

Will this harness fit my specific vehicle model and year?

Yes—Oyviny designed the 56217 harness to mate directly with the factory wiring on the listed vehicles. It fits 2008–2019 Toyota Highlander models and 2020–2021 Lexus RX 350/350L that were not originally equipped with a factory tow package. Compatibility relies on the factory connector type rather than aftermarket modifications.

• Fits Toyota Highlander model years 2008–2019
• Fits Lexus RX 350 and RX 350L years 2020–2021 without factory tow package
• Plugs into existing factory harness—no vehicle cutting
• Check your factory connector before purchase for final confirmation

How difficult is installation and what tools do I need?

Installation is intended to be simple: the harness plugs into the vehicle’s factory connector and provides a 4-pin flat trailer socket. The plug-and-play design removes the need for splicing or complex rewiring, making it suitable for most DIYers. Basic hand tools and a momentary check of light functions are usually all that’s required.

• No cutting or splicing—direct plug into factory harness
• Inline fuse holder included for circuit protection
• Rubber dust covers protect connectors during installation
• Basic tools recommended: pliers, screwdriver, and electrical cleaner

What materials and protections does the harness include?

The Oyviny harness pairs an ABS plastic converter housing with pure copper wires to balance strength, flexibility and electrical performance. The 4-way flat connector and fuse are fitted with rubber dust covers to help resist water, dirt and corrosion, while the inline fuse holder reduces the chance of damage from electrical faults.

• Pure copper conductors for reliable conductivity
• High-strength ABS converter housing for durability
• Rubber dust covers on connector and fuse for moisture protection
• Inline fuse included to guard against current damage

What lights and trailer functions will this harness support?

The 4-pin flat output supplies standard trailer lighting: running lights, left and right turn signals, and brake lights. It does not provide a dedicated feed for trailer brakes or auxiliary power; those features require a 7-pin or separate brake controller wiring solution. For typical small trailers, bike racks or cargo carriers, the 4-way format covers the essential lighting needs.

• 4-way flat connector: tail, left/right turn, brake lights
• Not intended for electric trailer brakes or constant 12V power
• Works for small to medium trailers and cargo accessories
• Use a separate 7-pin kit for brakes or battery charging functions

Who is this for: The Oyviny 56217 harness is aimed at Toyota Highlander and compatible Lexus RX owners who need a reliable, factory-style trailer lighting connection without altering the vehicle’s wiring. It’s ideal for DIY installers, weekend haulers and drivers pairing small trailers, cargo carriers or accessory racks who want durable materials, pure copper wiring and simple plug-and-play setup.