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Say goodbye to the mess of cutting and splicing wires! The T-One Vehicle Wiring Harness is specifically designed to seamlessly fit a wide range of vehicles, plugging into your existing wiring setup with ease. It's an ideal solution for those who want a quick, hassle-free installation process, turning what once seemed like a daunting task into a straightforward DIY project. With no complicated wiring, you can maintain your vehicle's integrity and get on with your adventures much faster.
Worried about overloading your vehicle's electrical system? The built-in ModuLite power module ensures your trailer lights are powered without straining your car's circuits, drawing power directly from the battery. This savvy integration means you can connect your trailer with peace of mind, as it safeguards against electrical shorts and unwanted surprises. The result? A reliable, safe, and efficient trailering experience every time.
Dust, dirt, and the elements can be tough on electrical components, but with the T-One Harness, you’re covered. Equipped with a durable 4-way flat trailer connector inclusive of a dust cap, this harness is built to withstand the harshest environments, keeping your electrical connections clean and secure. Whether you're towing through heavy rain or dusty trails, rest assured your connection remains rock solid.
This trailer wiring harness isn't just limited to basic setups. It can seamlessly operate with 5-pole, 6-pole, and even 7-pole adapters (sold separately), making it extremely versatile for various trailering needs. Whether you're towing a small utility trailer or a more complex setup, this harness is ready to adapt, giving you the flexibility to hook up to a wide range of trailering solutions as your needs change.
Durability is never out of style. Constructed with high-grade 16-gauge bonded wire, the T-One Vehicle Wiring Harness is designed to endure the rigors of trailering without faltering. This robust build means fewer worries about wear and tear over time, giving you a dependable setup for countless journeys ahead.
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It works!!! I have a 2021 Lexus RX450h F-Sport WITHOUT the tow package (there is a different product if you have the tow pkg). Step 1: If you need help installing a CURT hitch, go to [online] and look at the videos. (I removed the bar and installed *w/o* cutting into my trim by buying some spacers from Metal Masters). Step 2: Connect the grey tip wiring harness underneath the driver's side undercarriage (see photo); I store everything underneath & did not mount. Step 3: Inside the trunk, pull up the cover over the spare; remove the passenger side storage compartment (the carpeted area picks up easily; press the push pin to release the button and pop it out); connect the white 10-pin (see photo); replace everything. Step 3: Open the large fuse box in the engine compartment and put in a 30 amp mini-fuse (see photo). Step 4: Test. Note: I used a probe detector and it does not work on trailers; Instead, connect it to the actual trailer or go to [online] and have it tested. Would have taken me less than 30 min. had I known all this! THANK YOU, ETRAILER!!!
Still waiting to take car to Lexus for them to tell me where to connect. My Lexus,22 RX 350 primers does not allow to connect into connector in back trunk area. There is another connector already plugged into it.
Jenny N.
2/22/2024
It is possible that your Lexus has a tow package. Were you able to install the second part of the harness that has the 4 flat connector at the connection point behind the bumper? If not, please go ahead and then test the 4 flat for the signals. You can do that using a circuit tester or you can plug into a trailer. If it has the tow package then all you will need is the connecter harness that has the 4 flat on it.
Joe L.
2/22/2024
Took the car to Lexus. Knowledgeable guy said 2022 RX 350 comes pre wired for towing. All that should be necesssry is your pigtail that connects under the left rear under the car to the flat 4 wire connector. However this is not the case. Checked fir the fuse under the hood, all good. Checked the fuse under the dash, all good. No power to plug under car. Tech found out there is a converter box inside car under back floor that is in line with power out to the flat connector. Going back tomorrow to hopefully figure things out. Just thought you guys needed to kniw
Joe
2/14/2025
Could not install product. Nowhere in trunk area was there a harness that Icoukd plug in to. Took it to Lexus and they installed a similar part somewhere , I never found out where, and charged me $300. A mystery.pig tail from under car to trailer hitch worked fine. Would like to return the part that did not fit anywhere as instructed.
Kate F.
2/14/2025
Wiring harness custom fit for my Lexus RX350 was plug and play. Just plugs into connectors which are already in place by the manufacturer. Literally ten minutes to install. Trailer lighting immediately worked.
I wrote detailed installation instructions for this kit, and I can tell you that I am very happy a year later. We gave installed them on both of our RX450h's even though the dealership wouldn't. Their reasoning is that if you didn't have the tow package, the hybrid shouldn't be hauling weight. I can understand that, but we needed bike racks & to haul small trailers. Love that it was easy to do & works great!
Installation instructions were great and the hitch fits and works perfectly. Additionally, everything is snugged up out of sight and appears to be a factory installation.
James
11/23/2024
Absolutely no issues since installation. Couldn’t be happier.
This website is terrific! There was a video to demonstrate the product I was buying which I appreciated. They provided detailed tracking information and fast shipping.
I know I’m supposed to review the product but couldn’t skip the above. Product works as expected.
Gwendolyn Y.
12/12/2024
Hey Melissa. Thanks for sharing all this with us! It truly means a lot and I'll make sure my to give everyone a fist bump for you.
am enclosing 2 pictures of my T-one wiring harness with 4-pole flat trailer assemblies for your records. This is regarding my order and I was requested by your office for a review and pictures of the installation. All went well, connected right up and as you can see the power cord unit was installed inside right well underneath the cargo holder where there was already the other connector to attach your harness. If there are any questions you can reach me on my e-mail. Thanks for everything.
etrailer is only place I was able to get the information I needed to add towing to my Lexus RX 350. This kit worked perfectly and your installation video was exactly what I needed to instal myself. The kit is plug and play and your video allowed a non-technical person like me to work like a pro. I truly appreciate and value your through product knowledge, it's what sets you apart and why Etrailer is the only place to go to.
Antonio
5/9/2024
Wow a year already, time flies for sure. The product is working perfectly. I am very impressed with it and with e-trailer. Honestly you have the products I need for towing, biking, storage etc. Great product, great service and thank you for following up.
Mike L.
5/23/2024
Product was exactly what I needed to make my towing lights get power. Easy hookup.
I recently purchased a hitch and wiring harness for my 2015 Lexus RX350. The hitch came as promised and I installed it in under 2 hours. I could have done it faster, but I just took my time and triple checked everything.
I had planned on installing the wiring harness at the same time, but it seemed to have gotten misplaced during shipping. Late Friday afternoon I sent an email to Customer service asking about the status of the wire harness. They emailed me back within about an hour and told me it had already been shipped and asked if I would double check to make sure it was not just placed in the hitch packaging.
I did another check and responded back that it was not there. They quickly replied back to me that they were sending out another harness. This all happened on a Friday Evening between 6:00 and 9:30 PM.
The next morning, I received confirmation from them with tracking information. The harness arrived the next week as promised.
They were fantastic to deal with it. Many thanks to Paula T in Customer Service.
Easy online purchase and installation on a 2022 RX450H. Highly recommend doing it yourself and purchasing from etrailer.com.
Gwendolyn Y.
4/21/2025
Hey Richard. Install looks great! What are you going to be carrying with your RX450H?
2016 RX 350. This kit is excellent. Installs easily on the 2016 RX. Remove the trunk cover to expose the spare tire area. Remove the first aid kit (velcro) from the passenger side rear wall. On inside corner cover, pry up the center of black plastic fastener and remove. Reach under the cover with small plier and squeeze hidden second fastener's prongs to pop the cover loose. The white connector for the kit's 10 pin adapter, located in the passenger side rear location will have a black rubber sheath. It is located slightly up and out of sight toward the rear of the vehicle. Secure the adapter to prevent rattling. I used the tab with hole on the adapter with a cable tie to an existing sheet metal hole and some duct tape to restrain the wires. The four-way cable connects to an existing grey connector under the driver side rear underside near the bumper. Loosen the locking tab with a small screwdriver and remove the connector cover. Connect the cable and use cable ties to strain relieve the harness at your desired location.
Shipping and customer service was great. I can’t speak to the product as it ended up not being needed
It took an hour to install this item, not complaining since I tend to move slower than most shade tree mechanics. It was fairly simple to do and it works just as advertised. Would recommend this product to others for sure.
Just remove the aft plastic, pull up the side covering and you will see the connector right there. I went ahead and secured the device using a sheet metal screw in a bracket that I drilled under the floor by the side container. See pics.
Did not need the trailer hitch wiring as this came with the Curt hitch. I now have a spare if needed.
The harness was well built and super easy to install
Excellent prompt personal service.
Website made it easy to select the correct components for my particular SUV.
Was kept informed throughout the delivery process, I knew exactly where my package was and when it would arrive.
Would certainly recommend using etrailer - a great and professional service.
Fitting the wiring was a breeze, once the appropriate socket for the trailer module was located (hiding behind the rear R/H side fascia panel)
Great service!
Just what I needed!
Delivered on time and in good condition.
Hitch was super easy to install, wiring was easy to install, the plastic cover on my Lexus needed more modifications then the video suggested. I was able to do but, was not expecting it.
Very easy to install. Works great
I’m not sure this is the correct harness for my vehicle. I cannot find definitive information about installation
Brooke M.
2/16/2024
It looks like this is a fit for your 2022 Lexus RX 350 if you dont have the factory tow package. If you do, then you would need part # 118252.
Both hitch and wiring went on flawlessly. However the right angle adapter to hitch frame assembly is difficult to install in the socket, likely will leave it in place due to difficulty locking in place.
Where my finger is point is where the connector is at. I just zipped tied this as you can see. Works awesome
Very informative video to help identify what parts I need. Parts installed as advertised and trailer lights work great!
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Mischa
12/3/2023
Love it! Works like a dream!