T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
(244 reviews)
Price: $49.94
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
Our Price: $49.94
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- All Info
- Reviews (244)
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Tekonsha Custom Fit Vehicle Wiring
- Custom Fit
- Trailer Hitch Wiring
- 4 Flat
- Powered Converter
- Tekonsha
Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required. Powered ModuLite reduces strain on wiring system.
Features:
- Provides a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights
- Compatible with 5-pole, 6-pole and 7-pole adapters (sold separately)
- Connects quickly and easily - no cutting or splicing of wires
- Tow harness with 4-way connector plugs into port behind rear bumper
- ModuLite connects in rear cargo area
- Includes ModuLite power module that connects directly to battery to avoid overloading vehicle's electrical system
- Constructed of 16-gauge bonded wire
- Comes with dust cap for 4-way flat connector
Specs:
- Maximum amperage:
- Stop/turn lights: 2.1 amps per circuit
- Tail lights: 5.6 amps per circuit
- 1-Year limited warranty
Installation
This custom-fit T-One connector plugs into your vehicle's wiring harness. The connection point for the ModuLite power module is located behind the interior trim panel in your rear cargo area. The 4-way tow harness plugs in just behind the rear bumper. Once you've made the required connections, insert the included fuse into the in-line fuse holder.
Once installation is complete, the 4-way flat 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 plugs on your automobile and the 4-pole connector itself - to help prevent corrosion.
ModuLite Power Module
A ModuLite power module is built into this T-One connector. With a ModuLite, your trailer's lights will be powered without overloading your vehicle's electrical system. Because the module draws power directly from your car's battery and bypasses the electrical routes that are used by a basic wiring harness, there is virtually no draw on your tail light circuits.
118255 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite
Item # 118255
Installation Details
This Product Fits The Following Vehicles
- 2010 - 2022 Lexus RX 350 without factory Tow Package
- 2010 - 2022 Lexus RX 450h without factory tow package
California residents: click here
Customer Satisfaction Score:
96% were satisfied with this product
4% of customers were not satisfied
- Wrong item was ordered
- Product did not meet expectations
- etrailer mistake
Customer Reviews
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118255
Average Customer Rating: 4.8 out of 5 stars (244 Customer Reviews)
Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required. Powered ModuLite reduces strain on wiring system.by: Mischa12/02/2022
2021 Lexus RX 450h
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!!!
by: Michael11/09/2023
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.
by: Joe02/13/2024
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
by: Edward 02/05/2024
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.
by: Dave03/24/2024
Very informative video to help identify what parts I need. Parts installed as advertised and trailer lights work great!
by: William02/10/2024
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.
by: Kerry03/19/2023
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.
by: Bob R03/08/2024
Super easy to install, video was very helpful. Will be ordering again from eTrailer. Live CSR call was great, they want to make sure everything is correct for your vehicle the first time. Great experience!!!
by: James11/23/2023
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.
by: Marshall03/03/2024
2017 Lexus RX 350
Super fast shipping. Great quality. Kept me informed from order to delivery. Will use again for my trailer needs. Good people and easy to work with.
by: Jim 03/30/2024
2017 Lexus RX 350
Great quality and easy installation.
by: David B.11/02/2017
2016 Lexus RX 350
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.
by: Jeff12/26/2018
2011 Lexus RX 350
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.
by: Christopher 09/10/2023
This product worked as described. My car now has a hitch with lights.
by: M10/01/2023
Plug n Play. Easy Peasy! It makes you wonder if that's all there is to it. I mounted the module using EZ-Pass type Velcro. I'm not real hip on drilling holes into my car.
I've never met Justin B. in person but Im pretty sure that he has big hair and wears leather pants because he's definitely a Rock Star!
He was very helpful in processing a return as well as expediting the shipping of a previous order I had placed.
by: Antonio05/09/2023
2013 Lexus RX 350
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.
by: William 03/31/2024
The item arrived when promised, and has worked great.
by: Hyler06/20/2023
If I would have known I needed the ten wire plug in harness as well as the four wire, I would have ordered from you first.The product came and took me all of twenty five minutes to pull panels and install.Afterwards had the voltage I needed.
Quality products
Thank you
by: Don06/09/2022
Fantastic service. Item purchased was exactly what I needed. Cost was 1/4 of what my car dealer would charge. Totally pleased with this company.
Don
6/10/2023
Wiring harness continues to work flawlessly. Glad I found this item saved money and does the job just fine.
by: Bob 02/24/2024
Worked great. Make sure when ordering you check to see if you need the power module, Some cars already have it installed and some do not.
by: Joseph 03/19/2024
Awesome product, w EASY install.
by: Paulo 03/29/2023
2017 Lexus RX 350
Hitch and wiring work great! I had my mechanic install. Hitch went on easy. The wiring harness took some time. Lexus advised I had the tow package. But the plug ended up being underneath the SUV. My mechanic had to reroute the plug up inside the SUV rather than have the whole wire harness dangle under the SUV. The whole job took 3 hours, which included an oil change.
by: BobA10/23/2020
2010 Lexus RX 450h
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)
by: Gary 04/05/2023
Product is exactly what was needed to make our trailer lights work properly but an addition to the instructions would help a lot. The connector in the vehicle was hidden & I almost gave up looking for it. The instructions led me to believe that the trailer harness was already hooked up to the vehicle and your harness listed above was not required.
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Show More Reviews
See what our Experts say about this Tekonsha Custom Fit Vehicle Wiring
- Installation of Tow Ready T-One Vehicle Wiring Harness 4-pole # 118255 on a 2012 Lexus RX450HTo install the Tow Ready T-One Vehicle Wiring Harness 4-pole # 118255 on a your 2012 Lexus RX 450H, the white plug that has a small black box attached to it plugs in to the vehicle wiring harness. This attachment point is located in the rear cargo area of your vehicle, and is on the passengers side. Then the gray plug that has the trailer 4-pole at one end will plug into the connection point underneath your vehicle. There is also a 10 amp mini-fuse included in this kit and that will have...
view full answer... - Trailer Wiring Recommendation for 2016 Lexus RX 350 without Tow PackageYes, for your 2016 Lexus RX 350 that does not have the factory tow package the correct trailer wiring kit you need is the part # 118255.
view full answer... - Trailer Wiring Recommendation for 2017 Lexus RX 350 without Tow PackageSince Lexus wanted to sell you a trailer wiring harness that includes a converter that would mean that your vehicle does not have the tow package. So for a wiring kit you would want the part # 118255 which is a confirmed fit for your vehicle and does have a converter.
view full answer... - Trailer Wiring Harness Recommendation for a 2011 Lexus RX450H without Tow PackageSounds like your 2011 Lexus RX450H does not have the tow package so there is a missing harness needed to activate the 4-way wiring. Because of that you would want the Tow Ready Wiring harness part # 118255 that you referenced as it comes with the converter harness needed and will activate the 4-way wiring port.
view full answer... - Why Would Known Working Trailer Lighting Not Work with Functioning Vehicle Trailer HarnessThe T-One harness part # 118255 that you installed taps in to the trailer wiring circuits of your 2013 Lexus RX 350. Most likely what is happening is that your trailer wiring circuits on your vehicle can't handle the amperage load of your trailer's lighting. Is there a significant number of lights on your trailer that are incandescent? Typically in those situations we have to recommend converting to LED lights. I attached a link to our page that has all of the LED trailer lights we offer...
view full answer... - Troubleshooting Dim Brake Lights on Boat Trailer after 4-Way Vehicle InstallWas your tow vehicle on? If the battery of the tow vehicle was drained from having the interior lights on because you had doors open on the vehicle to install the T-One Connector part # 118255 that would explain the dim lights. Other than that the problem would most likely be the grounds of the light assemblies. You will want to make sure the lights are grounding to a clean metal surface. Some assemblies ground through the mounting hardware so you will need to make sure they are installed...
view full answer... - Installing Trailer Wiring Harness for a 2010 Lexus RX 450hIf you haven't plugged in the converter box portion of wiring harness # 118255 (the part with the yellow fuse holder) then the 4-Way will not work until you do. Inserting the fuse in the fuse holder would be the last step. This harness is circuit protected. This means that if there is a short on the trailer it will not damage the vehicle wiring or electronics. You should not have to have the vehicle computer flashed or reprogrammed to use the harness.
view full answer... - Installation Instructions for T-One Wiring Harness on a 2018 Lexus RX 450h LYes we do have the instructions for the T-One Vehicle Wiring Harness # 118255 for your 2018 Lexus RX 450h L. I am linking the written instructions for you to check out as well as pictures of the instructions that you can reference. Since you're needing wiring for trailer lighting I'm guessing you plan on towing with your Lexus. In this case you'll also need a ball mount and hitch ball. I have attached our selections for you to filter through as well as a helpful article to help you determine...
view full answer...
- 4-Way Vehicle Wiring Harness For a 2022 Lexus RX 350 Without Factory Tow PackageWith your 2022 Lexus RX 350 not having the factory tow package you are going to want to use the T-One Vehicle Wiring Harness # 118255. I have linked an installation video at the bottom of the page for a 2021 RX 350 where we installed this same harness in our shop so you can see where to find the connectors.
view full answer... - Does Wiring Harness 118255 Fit 2015 Lexus RX 350 Without Factory Tow PackageYes, the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118255 will fit your 2015 Lexus RX 350 that does not have the factory tow package.
view full answer... - Will Tow Ready T-One Wiring Harness Fit 2011 Lexus RX450h Not Equipped With Tow PackageI contacted our representative at Tow Ready about the Tow Ready T-One Wiring Harness # 118255. The representative at Tow Ready informed me that the # 118255 will fit your 2011 Lexus RX450h that is not equipped with tow package. The # 118255 is a circuit protected harness which is designed to protect the vehicles sensitive wiring harness against shorts.
view full answer... - Added Running Lights to Trailer But they Will Not Light UpThere could be a couple of issues here. The more lights you add, the more power they draw. If the combined amperage draw of the lights exceeds the amperage rating of the vehicle side wiring system then either some lights will not light up or you could blow a fuse on the vehicle side. The solution is to switch everything over to LED lights which draw only a fraction of the power of incandescent lights. The other possible issue is a bad ground. You mentioned the lights you want to add have...
view full answer... - Finding 10 Pin Connector on 2018 Lexus RX 450h L to Install Trailer WiringFinding the 10-pin connector to install the Tekonsha trailer wiring harness part # 118525 that you mentioned on a 2018 Lexus RX 450h L is sometimes a bit challenging but we've had some customers come back and give us tips on where to find it. One customer said: "It is tucked up under the rear deck plate under the passenger taillight side. I used a mirror and flashlight to find it but realized that one I knew where it was I could feel it and pull it down just enough to plug the converter...
view full answer...
- Troubleshooting Install of Trailer Wiring in 2019 Lexus RX350 Where Pins Don't Seem to MatchJudging by the picture you sent in it looks like you are trying to use the wrong connector to install the # 118255 in your 2019 Lexus RX 350. I attached a picture to this page as well that shows your connector pictured very close to where the # 118255 plugs in so I can see how it would be easy to find the wrong one.
view full answer...
- How to install the T-One Vehicle Harness with 4-Pole Flat Trailer Connector 118255I attached a set of install instructions for the trailer wiring harness part # 118255 that you referenced below. In it you'll see a guide that will walk you through the process with pictures as well.
view full answer...
- Can't Find Plug To Connect Tekonsha Trailer Wiring 118255 To In 2017 Lexus RX 350The T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector part # 118255 is designed for a 2017 Lexus RX 350 without a tow package. Since the vehicle does not have a tow package there should be a 10-pin connector located behind the rear interior trim panel. It looks like you have found it but it is already connected to something which makes me think you already have a tow package if that is the correct 10 pin connector. If that is the case you should be able to plug the wire...
view full answer...
- Troubleshooting LED Tail Lights On U-Haul Trailer Dim With Tekonsha 118255 On 2016 Lexus RX 350When a harness like the Tekonsha T-One Vehicle Wiring Harness # 118255 on your 2016 Lexus RX 350 is causing the lights on a trailer to be dim, it is usually a ground issue. Since your harness does not have a ground wire that you need to ground to the frame, I recommend checking all of the connectors on the harness to make sure they are fully seated in the vehicle connectors. If they are fully seated then remove them and look inside the connectors to see if any debris go in, or if there...
view full answer... - Troubleshooting Installation of Tekonsha Wiring Harness 10-Pin Connector on 2019 Lexus RX 350Aside from what you already found, the best advice I can offer comes from another customer who installed the # 118255 on an RX 350. On the inside corner cover, pry up the center of the black plastic fastener and remove it. Reach under the cover with small pliers and squeeze a hidden second fastener's prongs to pop the cover loose. The white connector for the 10 pin adapter will have a black rubber sheath. It is located slightly up and out of sight toward the rear of the vehicle. I'm not...
view full answer... - Trailer Wiring Recommendation for 2017 Lexus RX 350 without Tow PackageWhile we don't have an install video yet for the Tekonsha trailer wiring harness part # 118255 which fits your 2017 Lexus RX350. I did attach a picture that covers the install with pictures where you'll find the harness. An additional wire needs to be ran to the vehicle battery as well. I attached a help article that covers how to do that too.
view full answer...
- Recommended Wiring Harness for 2015 Lexus RX350 Without Factory Tow PackageThe Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector # 56083 is only a fit for a vehicle with the factory tow package. If you have the factory tow package, then you may have fuses that are missing or bad. The dealer should not need to do anything. If you don't have the factory tow package, then that harness will not work. You will instead want the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118255. This harness has...
view full answer... - 4-Way Flat Vehicle Wiring Harness For a 2022 Lexus RX 350For your 2022 Lexus RX 350 the Curt T-Connector Vehicle Wiring Harness # 56083 will connect to the factory tow package with no other parts required. This will give you a 4-way flat trailer connector on your Lexus. Currently the T-One Vehicle Wiring Harness # 118255 is only confirmed to fit the 2010-2021 RX 350 that has the factory tow plug. It is possible for your Lexus to have the tow plug but not have came with the factory tow package.
view full answer... - Troubleshooting Blown Tail Light Fuses with a Non-Powered Tail Light Harness on a 1999 Lexus RX300Sounds like your trailer is overdrawing your tail light circuits and that is why the fuses are getting blown. Having a powered unit does make a big difference for this issue. A powered unit will basically only use the tail light wiring as signal wires and then draws all the power for the trailer tail lights directly from the battery. This protects the delicate tail light wiring and prevents problems like what you are experiencing. I think your best option at this point would be to install...
view full answer... - Troubleshooting No Power at Factory Port on 2017 Lexus RX 350 without Factory Tow Package If your 2017 Lexus RX 350 didn't come with the factory tow package then an additional harness with a powered converter is needed to actually activate the plug that you used to install the Tekonsha T-One Vehicle Wiring Harness # 118252. This Tekonsha harness is designed for vehicles that came equipped with the factory tow package. Unfortunately, the converter harness is not available as a separate item from the manufacturer so your only option is to get the Tekonsha T-One Harness # 118255...
view full answer... - Trailer Wiring for 2019 Lexus RX 350We have two really great and easy to install trailer wiring harnesses that fit your 2019 Lexus RX 350. We have the Tekonsha kit part # 118255 for if you do not have the factory tow package, or if you did have the tow package part # 118252 which is just the 4-way connector of the # 118255. Most reliable and efficient way to determine if your vehicle has the tow package is to contact a Lexus dealer with your VIN and they'll be able to look up what options the vehicle came with.
view full answer...
Do you have a question about this Custom Fit Vehicle Wiring?
Info for this part was:
Expert Research:
Mike L
Expert Research:
Michael H
Expert Research:
Reno H
Expert Research:
Jameson C
Expert Research:
Adam R
Expert Research:
Rachael H
Installed by:
Jeff D
Video by:
Kathleen M
Video by:
Cooper S
Updated by:
Laura H
Updated by:
Wilson B
Updated by:
Alexander C
Updated by:
Isabelle B
Test Fit:
Randy B
Test Fit:
Bradley B
Video Edited:
Chris R
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Mischa
12/3/2023
Love it! Works like a dream!