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Tekonsha

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Part Number: 118397

53 Reviews | 12 Questions

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$61.63

Retail:$93.35

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2004 Ford Van

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Product Images

tekonsha custom fit vehicle wiring trailer hitch end connector

tekonsha custom fit vehicle wiring trailer hitch end connector t-one harness with 4-pole flat

tekonsha custom fit vehicle wiring 4 flat plug-in 118397

tekonsha custom fit vehicle wiring trailer hitch 4 flat 118397

tekonsha custom fit vehicle wiring end connector plug-in 118397

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In Use/Installed

2009 hyundai tucson custom fit vehicle wiring tekonsha trailer hitch 4 flat t-one harness with 4-pole connector

2009 hyundai tucson custom fit vehicle wiring tekonsha end connector 4 flat on a

2009 hyundai tucson custom fit vehicle wiring tekonsha trailer hitch plug-in on a

2009 hyundai tucson custom fit vehicle wiring tekonsha trailer hitch 4 flat 118397

2009 hyundai tucson custom fit vehicle wiring tekonsha end connector 4 flat 118397

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Videos

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector-118397 Spec Review

Install: T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector on a 2009 Hyundai Tucson

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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. Circuit-protected converter guards against shorts. 1-800-940-8924 to order Tekonsha custom fit vehicle wiring part number 118397 or order online at etrailer.com. Free expert support on all Tekonsha products. Great prices and Fastest Shipping for T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.

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Tekonsha Custom Fit Vehicle Wiring - 118397

Highlights

Custom Fit for Your Vehicle: Works with your vehicle's wiring
Tow-Ready Setup: 4-pole flat connector powers trailer stop, turn, and tail lights.
Plug-and-Play Install: T-One plugs inline with tail lights—no splicing or cutting needed.
Signal Syncing: Built-in converter ensures vehicle and trailer lights match correctly.
Reliable Grounding: Metal-to-metal ground connection keeps signals steady and corrosion-free.
Prevent Overload Issues: Converter rated at 2.1 amps per stop/turn circuit for safe operation.

Features to know about

Fast, No-Splice Setup: Plug-In T-One Harness

Wiring for towing can be a hassle if you have to cut and splice into factory lines. The Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector plugs directly into existing tail light wiring. There’s no wire cutting or taping—just connect it at each tail light and it’s ready to go. Most installs wrap up in about an hour, and experienced hands can have it done in just minutes.

Built-In Converter Protects Vehicle Wiring

Trailer lighting draws more power than most vehicle circuits are built to handle. This harness includes a converter that keeps the trailer load isolated, so the vehicle’s own wiring isn’t overloaded or damaged. If the lights ever stop responding correctly, it’s easy to test the input and output sides of the converter with a circuit tester to pinpoint the issue.

Reliable 4-Flat Connection for Trailer Lights

The 4-pole flat connector provides all the basics—running lights, turn signals, and brake lights—so trailers, cargo carriers, and light-duty haulers work as they should. A solid ground keeps the signal steady and helps prevent flickering or shorts. If corrosion builds up over time, cleaning the connector restores full function quickly.

Hidden Design Keeps Wiring Out of Sight

Once installed, most of the wiring stays tucked away behind trim or panels, keeping things looking clean. The only visible part is the 4-flat plug that’s ready for your trailer connection when you need it. When not in use, it can be stowed safely inside to keep it protected from dirt and weather.

Specs

Image:
Layout:

118397 Tow Ready T-1 T-Connector - 4 Wire

Installation Details 118397 Installation instructions

This Product Fits The Following Vehicles

2005 - 2009 Hyundai Tucson
2005 - 2009 Hyundai Tucson

Customer Satisfaction Score:

92% were satisfied with this product

8% of customers were not satisfied

4.8

53 reviews

5 Stars		(47)
4 Stars		(3)
3 Stars		(1)
2 Stars		(2)
1 Star		(0)

by: Randy 05/12/2026

2008 Hyundai Tucson

I just installed the harness after watching your video, and the install was a breeze! Thank you so much!

by: Steve N - Minnesota 09/19/2013

This is the second time I have purchased from e-trailer and they provide a wonderful service before and after the sale. The ordering is very easy on their site due to the great search engine for finding the correct items for an individual vehicle.

As for the products- well installing the wiring harness too me about 45 minutes and most of that time was spent in removing/re-installing the trim panels and tail lit assemblies. As a computer professional I only wish some of the software could be as much "plug&play as these wiring harnesses are. Every this is provided in the package and instructions are very clear and concise.

I recommend e-trailer and the T-One wiring harness to everyone needing to do a new install.

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by: Kyle 03/19/2026

2005 Hyundai Tucson

Was very easy to connect to the tail lights and works perfectly!

by: Jeff G. 05/08/2013

2005 Hyundai Tucson

This,by far,was the easiest time I've ever had wiring a vehicle for a trailer.The harness for a 2005 Hyundai Tucson fit perfectly-no worries
about anything not fitting,or not enough wire to reach both sides.I was
finished in about 20 minutes and was honestly stunned.
The harness arrived faster than I thought it would,and was well pack-
aged.Thanks for the great service,and I am extremely happy with the
product.

Jeff G. One Year Later

6/9/2014

Still consider it the easiest tow wiring Ive ever done.

by: Chris K 04/17/2016 One Year Later

2007 Hyundai Tucson

I purchased a hitch receiver kit for a Hyundai Tucson about a year ago. Since I am not super car savvy, I had my local shop install the hitch for a very reasonable price. Everything turned out great and I pull my boat behind the truck fairly regularly. The product works just as it is supposed to. It was shipped out in a timely fashion, also. In addition to the hitch kit, I also purchased a lighting harness to run from the truck to the trailer. I installed that myself in about 20-30 minutes. The instructions were easy to follow and I have had zero problems with the lights. Great products and great service. I would highly recommend!

by: Sheila 04/25/2022 One Year Later

Was easy to install & works perfect. Price was for harness was reasonable & no cutting wires everything plugs in.5 stars. Also the trailer hitch,was easy to install bolts line up perfectly took my husband about 1 & half hours to harness & hitch & he took his time.

by: Wayne C. 08/20/2016

2008 Hyundai Tucson

All the way from Purchase to shipping and installation went great. I've wired a couple trailers in my day but this was the first time I traced the problem to the vehicle's connections. Once I found the part on ETrailer.com I found their installation video for my vehicle. I compared that to the existing wiring and found the manufacturer had used a similar wiring adapter when we originally purchased the car. That unit had failed. No power was coming out the adapter plug causing all the trailer lights to fail. Again using Etrailer.com's video I was able to easily unhook the bad unit and install Etrailer.com's wiring to fix the problem.
Even how to remove the vehicle panel's and rear lights came in very helpful.
If you've never removed a rear tail light on some vehicles it can be a very trying thing not trying to break connectors or other parts of the vehicle. All in all once the wiring and module was connected and hooked to the trailer I was so relieved to see the tail lights do their job again. No more towing and waiting for a ticket :)

by: Phil s 03/28/2017 One Year Later

Works as advertised, shipping was fast and instructions were super simple. Great customer service too!

Phil S. One Year Later

3/28/2018

Fantastic, no problems!

by: Ervin J. 10/03/2014

2005 Hyundai Tucson

Hi Carla M., The Curt Trailor Hitch Receiver that you recommended for my 2005 Hyundai Tucson fit like a glove. The directions were great and it took less than an hour to install especially since my good friend has a lift in his garage. Basically all you see is the 2" receiver end. It's awesome. The Wiring Harness was a little more challenging to install and fortunately my good friend had all the right tools,and as a former autoshop teacher, the knowledge to go along with them. Don't know if I could have hooked the harness up by myself.

by: Durwood 12/07/2019

With the help from your [online] video it was easy to install it took only 30 minutes. The only difference between the video and the item I received was that I had to secure the transformer box there was no double-sided tape on it but it was easy to do thank you

Durwood One Year Later

12/8/2020

Awesome

by: Jason 01/25/2012

2006 Hyundai Tucson

as I thought it was a little pricey, and figured I could splice the wires myself. Not to mention I wasn't sure how well it would "ACTUALLY" fit with the factory wiring. It could not have been a more perfect fit. Wires were plenty long enough, all connectors fit perfectly, wire seems to be a good gauge for the application. Installation took me about 20 minutes from start to finish. It was a breeze. I would buy this product again and recommend it to anyone. Thank you etrailer.... well done!

by: Lance 09/02/2016

2008 Hyundai Tucson

That was by far the easiest install I've ever done. Thanks etrailer for the great install instructions and expediting my order so quickly. I hated to pay overnight shipping but couldn't find this harness anywhere in town and was on a time crunch. All lights functioned after installing. Now off to buy my trailer! If I had any negative feedback, my kit didn't come with the double sided tape for converter. I improvised and secured it with a screw. Probably a better way to install converter anyway. Can't go wrong ordering from etrailer!

by: erin S 08/14/2013

2005 Hyundai Tucson

Very easy to install, hardest part was drilling in the ground to the vehicle. Have yet to tow anything, but the lights still work so that is always a good sign.

by: Joel S. 03/31/2015

The installation video makes installing this on your vehicle a breeze- takes 30 minutes tops, very helpful operator when ordering, all in all, etrailer makes picking out the parts you need very easy, and their service is great- I'm very pleased!

by: Tyrone S. 05/15/2012

2005 Hyundai Tucson

a little bit of patience and understanding, then you will have no problems putting this harness in. Took me just around 1 hour, and that includes cleaning everything that I removed. Instruction were good and accurate. Will buy all my trailer wire harness's from etrailer.com from here out!

by: John 03/19/2018

2007 Hyundai Tucson

Great video online on how to install the kit. Worked perfectly.

John One Year Later

3/19/2019

Still going strong! No issues! Great product.

by: Jeremy H. 04/19/2013

2005 Hyundai Tucson

This wiring harness makes hooking up wiring a breeze. I had it done in no time. I would highly stress being careful removing the tail lights. There are a couple of clips that are super thin and easy to break.

by: Tom 06/28/2009

So quick, harder to read the instructions than do the job. Took about 35 minutes. This is the only way to go. I've installed brand X, which is cheaper, but always end up trying to figure out which wires to spice into and always end up doing it wrong the first time. Brand X is always a 3 hour or more job. This system is so slick, nothing to mess up and worked right first time. This "T" connector system is terrific.

by: GMan 09/16/2011

Like that entire harness is inside the vehicle and won't get wet when not in use. Only issue is that to connect to trailer, I have to close the cargo door on the 4-wire cable. I don't want to sharply bend the cable. Must be a better way.

by: Sussanne 05/31/2007

I installed the wiring myself. It was so easy! Took less than an hour to install hitch and wiring. It really surprised me how easy it was and it works!

by: DeWayne U 10/16/2014

2007 Hyundai Tucson

Fast delivery, easy and clear installation instructions!!!

by: David 06/19/2024

Have not recieved it yet should have been delivered with the hitchat the same time

by: JJ 04/02/2014

This product was shipped quickly and very easy to install. Etrailer is the best site for your trailer needs!

by: Derek 05/26/2019

2009 Hyundai Tucson

Hitch and harness I ordered came very quick! They were exactly what I needed and the instillation was fast and easy. I would definitely order from here again.

by: Ryan 08/11/2016 One Year Later

Wiring was straight forward and direct plug in. I couldn't have asked for an easier install.

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See what our Experts say about this Tekonsha Custom Fit Vehicle Wiring

Do you have a question about this Custom Fit Vehicle Wiring?

Everything Needed for a 2005 Hyundai Tucson to Tow a Trailer
You will need five separate parts to tow a trailer with your 2005 Hyundai Tuscon. You will need a trailer hitch, a ballmount, a pin & clip, a hitch ball, and a wiring harness. You have 7 different hitch options for your Tuscon. I would recommend purchasing and installing a hitch with a 2 inch receiver opening over a smaller 1-1/4 inch hitch opening; the larger hitch will give you a lot more options for accessories. Also, we happen to have a very competitively priced Curt Class III Trailer...
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Trailer Hitch and Wiring for a 2005 Hyundai Tucson
Curt trailer hitch # C12126 for your 2005 Hyundai Tucson is rated for 300 pounds tongue weight and 3,500 pound gross trailer weight like you said. It is one of the easier installs because it uses factory weld nuts inside the vehicle frame. You will likely need to clean out the weld nuts prior to installing the hitch. I have included some links that will help with that. According to the owner's manual the vehicle itself is rated for a maximum of 150 pounds tongue weight and 2,000 pounds...
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Troubleshooting Trailer Wiring On 2005 Hyundai Tucson that Does Not Allow Turn Signals with Brake
Sounds like you may have installed a trailer wiring harness on your 2005 Hyundai Tucson that was not designed for it's taillight configuration and that's the cause of your issues. So the best solution I can give you is the correct trailer wiring harness fit for your vehicle which is the Tekonsha kit part # 118397 which will allow your taillights to keep working as well as will operate your trailer taillights as needed. I attached an install video for this kit on a similar 2009 Tucson...
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2009 Hyundai Tucson Towing Capacity and Hitch
The Curt trailer hitch part # 13526 that you referenced does fit the 4 cylinder 2009 Hyundai Tucson that you have. This hitch has a capacity of 3,500 lbs trailer weight, but it looks like your Tucson is only rated to tow up to 1,000 lbs so that would be the figure you'd need to stay under. For trailer wiring you'd then want the Tekonsha kit part # 118397 as it's our most reliable option and doesn't require splicing to install. Since you plan on doing some towing you might be interested...
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Tail Light Converter on 2008 Hyundai Tucson Keeps Shorting Out
If you have a harness that is currently acting up, you can use a circuit tester like part # PTW2993 and do some troubleshooting on it. You can activate the right turn signal, then use the tester to check the green wire on the input side of the converter box to ensure that the signal is reaching the box. Then, test the green wire on the output side to make sure the signal is leaving the box. Repeat the same test with the yellow left turn and brown running light wire, checking both the input...
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Installing a Brake Controller from Scratch on a 2006 Hyundai Tucson
In order to install a brake controller, you will first need to install a 4-Way wiring harness if your 2006 Hyundai Tucson does not already have one. You can then install the 4- and 7-Way Installation Kit, # ETBC7. For a brake controller, I recommend the Tekonsha Prodigy P2 Brake Controller, # 90885. I have included a link to the installation details below. The correct 4-Way harness is the Tow Ready Custom Fit Vehicle Wiring, # 118397. This is a T-one style connector that plugs in line...
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Recommended Trailer Hitch for 2007 Hyundai Tucson
I do have a solution for you, however the Draw-Tite Sportframe Trailer Hitch Receiver # 24757 referenced in your question is designed for certain model years of the Hyundai Sonata and is not compatible with your 2007 Hyundai Tucson. For your Hyundai Tucson, I recommend the Draw-Tite Class III Max Frame Receiver Hitch # 75561. This is custom-fit for your vehicle and will provide a nice 2 inch receiver opening and a 3,500 pound towing weight capacity. No drilling will be required during...
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Trailer Hitch and Wiring Recommendations for a 2005 Kia Optima and 2008 Hyundai Tucson
For the 2005 Kia Optima, I have included a link to the installation instructions for Curt hitch # 24709. For the 2008 Hyundai Tucson, I have included a link to instructions for Curt hitch # 13526. The Curt hitch for the Tucson is the most popular hitch option for that vehicle. The Tucson will also have the higher towing capacity of the 2 vehicles if trailer weight is an issue. For the Optima I recommend going with the Curt trailer hitch # C11216 because it installs just a little different...
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Installation Instructions for Tow Ready Trailer Wiring for a 2009 Hyundai Tucson
We have not yet had the opportunity to install trailer wiring harness # 118397 on a Hyundai Tucson yet so I do not have any pictures or a video. But, what I do have is a link to the installation instructions that do contain some pictures that will help show where the harness installs. Basically, you will need access to the wiring that goes to each tail light.
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Why Torque Specs are Not Listed and Trailer Hitch and Wiring for 2006 Hyundai Tucson
Because the manufacturer of a given trailer hitch could change the torque specs we do not publish them on the site. But the instructions we have linked for a hitch, which I have also linked for you here, always have the most up-to-date specs in them. So if you look at step 4 in the linked instructions that is what you are looking for. I have also included a link to a video showing installation for you. If you plan on doing some towing you might be interested in etrailer ball mount kit...
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Left Brake Light Not Working After Installing Cargo Box With Lights on 2006 Hyundai Tucson
If the cargo box that is on the back of her 2006 Hyundai Tucson has lights on it, then there is a possibility that something is not hooked up correctly or has come disconnected. I would start by checking the trailer wiring connector on the 2006 Hyundai Tucson, part # 118397 and make sure it is working correctly and not corroded. Also, make sure it has a good ground connection with metal-to-metal contact. Also check to make sure all the wiring points are good. If the connector is not...
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Do You have Instructions for T-One Harness 118397 for a 2008 Hyundai Tucson
We do have the instructions available for part # 118397 for a 2008 Hyundai Tucson. I have linked them below. Our installers can do these in as little as 5 minutes. I looked at the instructions and it should not take more than 1 or 1.5 hours, depending on mechanical ability and skills. Take a look at the instructions. They will give you a prety clear idea of what is involved.
view full answer...

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Info for this part was:

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Video Edited:

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Updated by:

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Updated by:

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Updated by:

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Updated by:

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Installed by:

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