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Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. Connector plugs into OEM tow package port - no cutting, splicing or tapping required. Converter is made using SMT to ensure superior performance.
Features:
Specs:
Installation
This custom-fit T-connector plugs into your vehicle's factory tow package wiring harness, which is located behind the driver's-side interior trim panel in your rear cargo area.
Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location within your cargo area.
It is recommended that you use a small amount of grease on all electrical connections - the plug on your automobile and the 4-pole connector itself - to help prevent corrosion.
A tail light converter is built into this T-connector. Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your vehicle's three-wire system need to be combined so they are compatible with the wiring system of the trailer. This converter combines the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights. Note: This will not affect how the tail lights on your vehicle operate.
Curt builds each tail light converter using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability and durability.
Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? Curt converters also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.
Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.
California residents: click here
Great product, Curt trailer hitch & wiring.
Decent price, free shipping arrived in 2 days!
Perfect, thank you!
Fit n works perfectly. I would Definitely recommend this company!! My hitch fit perfectly also. Thank you
Great product easiest wiring job I ever had to do just plug and play I'm beyond satisfied with with the company and product recommend it to anyone
A couple of Saturdays ago I installed the C56107 Curt T-Connector Factory wiring harness for Factory tow package on my 2004 Toyota Highlander.
The installation was very easy once I removed all of the panels in the back of the Highlander. I purchased this vehicle new in 2004. The dealer showed us how the 3rd row seating would look by setting up the third seat. Since that day I've never had the cause to open it up again.
Once all of the panels were removed I quickly located the factory plug. It only took a second to plug the connectors together. Using the two-sided tape provided I stuck the controler to the outer fender wall. I cut a hole in the side of the small bin to allow the plug entrance to the bin. If you don't have a rollup cover that fits just in front of the jack holder you might not have to perform this step. I'm not sure. From that point it was just a matter of reinstalling all of the parts removed.
All parts of the trailer lights controller worked perfectly. I tested it with a plugin tester following the install. I did have to add a 20 amp mini-fuse to the box under the hood.
I've attached several pictures that I took along the way.
Thanks for a great product. I recommend it highly.
If your Highlander already comes with the factory tow package this Curt wiring harness is the quickest and easiest to install. I used the installation video for the Tekonsha wiring harness with tow package which was great. The advantage of the Curt wiring harness over the Tekonsha is that you don't have to install the white ground wire. You simply access your factory tow wire, plug in the Curt wiring harness and that's it! And if you don't have a 20amp mini fuse already in your car fuse box in the tow spot then you will need to pop the hood and put one in which takes about 10 seconds. Best plug and play option available.
Product fit perfectly, and working well. Thank you!
Everything works very well!
Easy to install on my 2006 Toyota Highlander tow package
Always very easy to order from e traile r!!
It was a great product, it fit perfectly it's still working good. I recommend it. Thanks!
Thank you. It fit and works great.
Fit perfect easy instructions and everything I needed. Did have to add the 20 Amp fuse under the hood for Trailer.
Best, most reliable place to get what you need, for your trailer. Efficient, effective website offers perfect specifications tailored to your particular vehicle. I quickly found a custom pigtail electric harness for my old (2007) unusual (hybrid Highlander) Toyota that had a built in fuse (protecting my car fuses) and a plug-in that fit to my vehicle wiring harness exactly. Quick shipping and handling, and great personal attention when you need it! I'll be back, and highly and unconditionally recommend etrailer.

Archie
12/8/2018
Still doing great!
Wiring harness was easy to install and hook up to trailer. Has been working well now for over a year
Easy, perfect fit for my vehicle.
Everything fit perfectly on my 2007 Highlander. The receiver looks great and the wiring for the trailer lights was really easy and successful.
To be honest, I don't remember what vehicle this is for, as I have installed several hitches on friends and families vehicles.
To say the least, etrailer is THE place buy hitches and light kits, as they are the best price, the quickest shipper AND the videos they provide that explains the installation, they are a "tree-men-dus" (said with excitement!) help! All the hitches and light kits I buy and install a "stupid" easy to do! All the hitches and light kits are of high quality and will outlast the vehicle they are installed on!
We were very pleased with our trailer wiring harness for our Highlander it was very quick and easy to install since we had a connection in the back of our Toyota just plugged it in and hooked up the trailer and ready to tow our trailer. No headache of figuring out the wiring system and rewiring. Thank You so much. We are a very happy customer and will be back as a need arises.
I will never buy anything else but this product ever again. I bought this hitch and a Curt custom wiring kit for my Toyota Highlander. So easy !!! everything plug right in and bolted directly up in my driveway. NO KIDDING. I installed both hitch and wiring in 30 minutes Flat !!!! Excellent. Im no mechanic !
This installation was literally a snap to put together! All I did was snap the connections together, snap in a couple of fuses and secure the adapter to the inside of the trunk space. I had such a difficult time trying to find a wiring harness that I could install myself for my 2007 Toyota Highlander Hybrid with tow package before finally coming across the experts at etrailer! I had been thoroughly confused by the other website's wiring harness determination for my vehicle and had to return the initial one I had purchased from them because it wasn't for the hybrid even though it said it was. I was also quoted over $300 at my local Toyota dealership for the harness, wiring and labor installation. Then I was quoted over $200 from the trailer rental place, where I would have had to drive about 3 hours away for the installation. These were not ideal options for me, or anyone for that matter. I emailed etrailer after months of reading threads about how other people were having the same problems I was with locating the correct wiring harness for my specific vehicle. They were prompt in their response and very thorough in their suggestions and pertinent information for the wiring harness I needed. The part and shipping ended up costing me less than $30! I'm EXTREMELY HAPPY with my purchase!!!
Haven't used with a trailer yet, but will do so in a few weeks. Vehicle is a 2007 Toyota Highlander hybrid. Directions are not completely clear which of the three (or that there would be three possibilities) connectors in the vehicle to use. First two are much more visible, but are incorrect. After digging around in rear of vehicle, found the third correct connector. After that, it was very easy to install. Tested with multi-meter and appears to work correctly with flashers,turn signals, and brake lights.would be nice if these were labeled for the flat 4 plug connector to make testing and any troubleshooting easier.
Overall my experience was excellent. The videos helped me fit the hitch and wiring. The job was done in less than an hour. I recommend looking at videos and keeping them close especially during wiring. Not difficult but get details right first time to avoid going back!
One caveat with this. I wish it was in bold letters that hitch pin does not come with the three mounted ball. I put the whole thing together and because I did not buy the hitch pin( thought it came with three ball mount) I could not use the hitch straightaway. You would think they should add small amount of money to ball mount and throw in hitch pin in the box!!!!
Always a professional experience with etrailer. Thanks

Mark
2/10/2024
I have bought 4 hitches, and 1 bike rack. Every product arrived on time and fits and works perfectly. I recommend Etrailerr to all my friends and customers at my auto repair shop. Thanks
I tried to get the correct wiring from my local Toyota dealer, they ordered the wrong part twice! They couldn't seem to find the right part in their manuals!
I came back to etrailer where I got my hitch, and found the right part immediately. It was exactly right, came with clear installation instructions, and works great! Amazing customer service, fast shipping and accurate parts!
After spending a number of calls to a couple of dealerships trying to order a factory wiring harness for my '05 Highlander, my frustration finally met its limit! Not only was I given wrong part numbers, but it wasn't until the third call that I was informed that the part was no longer available.
Your harness was what I needed. It even has an in-line fuse! It fit the factory connectors...I am very pleased. I didn't mention that the price was much more agreeable as well.
Do you have a question about this Custom Fit Vehicle Wiring?
Condition: Like New
Notes: May have damaged packaging or minor cosmetic blemishes.
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David
2/11/2025
Still works great, no problems.