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

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

Item # 118538
Our Price: $58.86
Custom Fit Vehicle Wiring

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Tekonsha Trailer Hitch Wiring - 118538
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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. Powered ModuLite reduces strain on wiring system. 1-833-496-1390 to order Tekonsha custom fit vehicle wiring part number 118538 or order online at 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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  • Reviews (31)
  • Q & A (0)
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  • Why etrailer?

Tekonsha Custom Fit Vehicle Wiring - 118538

  • 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. Powered ModuLite reduces strain on wiring system.


  • 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
    • Locate connection points behind tail lights
    • Plug in T-connector
    • Run hot lead to car battery
  • Includes ModuLite to ensure that your vehicle's wiring matches that of your trailer
    • Powered module 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


  • Maximum amperage:
    • Stop/turn lights: 2.1 amps per circuit
    • Tail lights: 5.6 amps per circuit
  • 1-Year limited warranty


This custom-fit T-One connector plugs into your vehicle's wiring harness, which is located behind the driver's-side and passenger's-side tail lights. You will have to remove the tail light assemblies to access this harness.

T-One Connection Location Points Behind Tail Lights

Once you've plugged in the T-connector, run the hot lead up to your car battery. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery and insert the provided fuse.

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 Powered Tail Light Converter

A ModuLite power module is built into this T-One 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 your trailer. This power module functions as a tail light converter to combine 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.

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.

118538 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite

Installation Details 118538 Installation instructions

This Product Fits The Following Vehicles

California residents: click here

Customer Satisfaction Score:

Customer Reviews

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118538

Average Customer Rating:  4.7 out of 5 stars   (31 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. Powered ModuLite reduces strain on wiring system.


excellent plug and play set up. Hardest part is running Power wire from battery to rear of vehicle. removing taillights and installing Y harness was easy and makes connecting your trailers lights easy. I would leave the pig tail in the spare tire compartment until needed and then just run out the tailgate to connect to trailer when needed


Everything bolted up and went together as advertised. Hitch and wiring harness. Would definitely recommend


I've had them on my vehicle for a year and used it for two cross country moves towing a trailer and everything has held up beautifully!


Worked out great thanks


The wire harness fit perfectly, and was very easy to install.

2013 Mitsubishi Outlander

Hi, I finally got around to installing the trailer hitch and wiring set-up on my 2013 Outlander Sport. The weather was a factor as I have to work outside and at 78 years old I do not do good in the cold. Let me tell you what a pleasure it is to get something that installs and works like it is claimed to do. The hitch went on very easy( longer than 30 minutes tho because I move slow) and the wiring took a little longer but the instructions were very clear on both. I needed the hitch on my spouses vehicle to carry my mobility scooter. I put one on mine last year(also ordered from you) This will do the job. Thank you for the great service and products. JKH

2015 Mitsubishi Outlander Sport

husband laughed when I told him I ordered a wire kit for the trailer hitch he's old school and always just spliced in well he used the kit took about 45 minutes he was amazed it worked right the first time lol I think I said told you so would reccomend


Excellent customer service, Anna called to make sure I knew the name brand of the wiring harness would be different than I expected. Plus she was watching the order to make sure it went on the shipping truck right away because I needed it ASAP. When the product arrived it was easy to install and fit perfectly, I could not be happier.

Thank you so much, I will recommend you when ever I have a chance.


2012 Mitsubishi Outlander

Well, I had my doubts when U-Haul and my Mitsubishi dealer said that no wire harness was available for my 2012 Outlander Sport. Thank G for the internet. Their you were. With my wire harness. U-Haul was nice enough to install it for me and it's all good. Going sailing this weekend!


This Tekonsha Trailer Wiring Kit worked great. It came with everything that I needed to install it and had very good instructions.

2017 Mitsubishi Outlander Sport

Great product with well written instructions and all needed parts to install. It took a bit more time running the power wire on the inside of the vehicle but that was my choice as i did not want it on the outside. The only thing that I did which I think improved it was I used shrink tube over the supplied connectors for a cleaner and more protected connection.

2018 Mitsubishi Outlander Sport

First time order from etrailer. Just have to say etailer was a pleasure to deal with!! Great communication!! I will recommend to anyone! Thanks for the great service

2012 Mitsubishi Outlander

Installation took about 3 hours. The hardest parts were routing under the body of the car and removing all the interior pieces. Not the kits fault, just not the easiest tasks to do. The connectors for the tail-lights fit perfect, just like OEM. Be very careful when prying out the interior pieces of the car. The foam pieces surrounding the tire do not need to be removed on a 2012 Mitsubishi Outlander Sport.

2011 Mitsubishi Outlander Sport

The sales staff are more than a 5 star took there time and explained how it would be installed. Received the kit have not installed it yet opened up the kit and everything was exactly what the sales person had explained. I was told if i have a problem to call them with their fast shipping you can't beat it. Can't wait to start this plug and play project.

Mitsubishi Outlander

Product arrived on time and works well. The actually installation on an outlander sport isn't as easy and expected as you have to remove all interior panels in the back on the car... But still a good product and would do business again.

2015 Mitsubishi Outlander Sport

I was greatly impressed with the haste at which my order was recieved and processed. The product visually looks very well built and I'm excited to install it. I was very happy they were able to work with me in getting this part shipped to Alaska, now I gotta fly to the east coast install on my new car and drive it home with the new trailer I purchased as well.

Thanks again for your awesome customer service.


Install could not have been easier, everything is basicly plug and play. Total install time was about 30 min with basic tools. Could not be happier with this product.

2015 Mitsubishi Outlander Sport



Product arrived on time and in good condition. Product had good instructions and installed properly. Product works perfectly, as advertised. Thank you.

2014 Mitsubishi Outlander Sport

getting hitch installed monday . never had a problem good service and good products


My shipment arrived in a timely manner.
Installation took about 30 minutes couldn’t be more pleased


Thank you for the great service and fast shipping!!!
Tommy you were awesome!!!!


Received parts as ordered and on the date specified. Very happy with the product as it is very well constructed. Thank you for a great product.



Show More Reviews

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

  • Where to Connect the Power Cable For Trailer Wiring on a Mitsubishi Outlander or RVR
    The 12 volt power cable for the T-One Wiring Harness, # 118538, should be attached to the clamp that holds the battery cable on the positive post of the battery. I attached a photo showing this type of installation on another vehicle that should be helpful. I also attached a link to instructions and a video that should help out. The vehicle in the video is different but the wiring principle is the same. You would not want to attach the power wire to any other power source other than the...
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  • Routing Power Wire for Powered Trailer Wiring Harness Tips
    I attached a help article that covers how to route the power wire of a powered harness like the part # 118538 up to the battery of the vehicle. If you cannot find a hole in the firewall you can drill one or you can route wire to the outside of the vehicle in the rear of it and then run the wire up along the underside of the vehicle to the battery. If you drill a hole you will want to seal it so that you don't leak water into your vehicle. I had a similar problem with an older car and it...
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  • Which Wire is Ground Wire on 4-Flat Harness for 2016 Mitsubishi Outlander Sport?
    The ground wire of Wiring Harness # 118538 is going to be the white wire. As per the linked instructions, you are going to need to drill a 3/32" hole and secure that wire with the included eyelet and screw. The ground location should be on bare metal that is free from any type of rust.
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  • Mitsubishi Outlander Sport Trailer Wiring Recommendation
    Yes, the Tow Ready wiring harness part # 118538 will fit your 2015 Mitsubishi Outlander Sport so it would work well for you. The Curt Harness part # C56127 that you referenced also fits the 2014 and 2015 models.
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  • Will Draw Tite Hitch for 2014 Mitsubishi Outlander Sport Tow Small Utility Trailer
    For your 2014 Mitsubishi Outlander Sport the Draw Tite hitch part # 76098 would fit and work well. I check out the trailer you mentioned which is pretty lightweight and this hitch would easily work well with it. For wiring you'd then want the part # 118538 which is also a fit. If you wanted to do some towing you might be interested in etrailer ball mount kit # 989900. It comes with 2 ball mounts; one with a 3/4 inch rise or 2 inch drop and one with a 2-3/4 inch rise or 4 inch drop. It...
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  • Will 4-Way Connector of Wiring Harness # 118538 Fit Curt 4-Way Bracket # C58001
    Yes, the 4-way connector of the T-One kit part # 118538 that you referenced will fit the 4-way bracket of the Curt Easy Mount Bracket # C58001 that you also referenced since this bracket essentially fits all standard 4 and 5-ways.
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  • Trailer Wiring Harness for 2018 Mitsubishi Outlander Sport
    I have a much easier trailer wiring solution for your 2018 Mitsubishi Outlander Sport with the Tekonsha kit part # 118538 which plugs inline with the taillight connectors of the vehicle. I attached a link to the install instructions for this kit that shows exactly how it installs as well.
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  • Is Curt Trailer Hitch # C13079 Hidden Behind the Bumper on a 2012 Mitsubishi Outlander Sport
    All of the available trailer hitches for the 2012 Mitsubishi Outlander Sport will have the cross tube and the receiver visible beneath the rear bumper of the vehicle. I have included a link to the installation instructions for Curt hitch # C13079. It contains some good pictures that will show you what the hitch will look like once installed. The round tube design tends to blend more with the vehicle. If you plan on doing some towing, I recommend etrailer Ball Mount kit, # 989900, which...
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  • Recommended Wiring Harness for 2015 Mitsubishi Outlander Sport
    In order to connect the lights on your trailer to your vehicle you will require a wiring harness. If you do not have LED tail lights, I recommend the # 119250KIT ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit. This wiring harness is a universal fit and will allow you to control the signal lights on your trailer. If you do have LED taillights, I recommend the # 118538 T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. This...
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  • Hitch Recommendation for 2015 Mitsubishi Outlander Sport
    Good news! I was able to look up in your owners manual your vehicle's capacities. Your gross vehicle weight rating is 4,343lbs, your vehicle capacity weight is 827lbs and your maximum roof capacity is 176lbs. You can also look at the sticker in the driver's side front door jam. The sticker should list the GCWR, gross combined weight rating which represents the max weight of the tow vehicle + the trailer. If you subtract the weight of the vehicle (curb weight plus weight of passengers...
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  • Trailer Hitch Recommendation for 2018 Mitsubishi Outlander Sport
    For a 2018 Mitsubishi Outlander Sport the Draw Tite hitch part # 76098 is a confirmed fit and will work well. This is a 2 inch hitch which means it has higher capacities and has more accessories made for it. For trailer wiring you then would want the part # 118538 if you have LED lights or part # 119147KIT if you do not. If you wanted to do some towing you might be interested in etrailer ball mount kit # 989900. It comes with 2 ball mounts; one with a 3/4 inch rise or 2 inch drop and...
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  • Trailer Hitch Installation On 2015 Mitsubishi Lancer GT
    The Draw-Tite Sportframe Trailer Hitch Receiver - Custom Fit - Class I - 1-1/4" # 24885 is a confirmed fit for your 2015 Mitsubishi Lancer GT as long as you don't have the dual exhaust. There is no drilling required to install this hitch. The installation instructions state you will need a jig saw, cut-off wheel, or die grinder for enlarging the hole already present in the frame for the carriage bolt and block on the passenger side. I've attached the installation details which state...
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  • Wiring Harness Compatible with 2010 Mitsubishi Lancer SE
    If you had the 2010 Mitsubishi Lancer hatchback then there would be a plug in option using wiring harness # 118538, however since you stated having a SE we know you have a sedan and there isn't a factory plug connection for that vehicle. There is a great harness that is easy to install but it will require using quick splice connectors. It is the Tekonsha # 119147KIT. I've attached the installation instructions as well as a video to assist.
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  • Recommended Trailer Wiring Harness for a 2015 Mitsubishi Outlander Sport W/O Factory Towing Package
    The correct wiring harness for your 2015 Mitsubishi Outlander Sport without the factory towing package will depend on if you have LED or incandescent lights on the vehicle. If you have LED lights on your Outlander Sport, you will need the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118538. This will be a plug and play option, but you will need to run a line up to the battery for added power. If you have incandescent lights, you will need the Tekonsha Upgraded...
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  • What is the Difference Between CURT Trailer Hitch # C13079 and # 13581, 2011 Mitsubishi Outlander
    Basically, the trailer hitches you are looking at fit 2 different vehicles. The CURT Trailer Hitch, # 13581, is designed to fit NON-Sport models of the 2011 Mitsubishi Outlander. If you have a Sport model, you would need CURT Trailer Hitch, # C13079. The vehicles have different mounting points and dimensions so they require different hitches. I have included a link to the installation details for both hitches for you to view. With either hitch, I recommend etrailer Ball Mount kit,...
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  • Ground Clearance on 2011 Outlander with Curt Class II Receiver # C12048 Installed
    As we have not yet had the opportunity to install that particular hitch on a 2011 Outlander, I do not have any exact measurements available for you. However, Curt tells me that when the # C12048 is installed, the top of the receiver will be within 1/2 an inch of the bottom of the fascia under the bumper (see photo). The outside dimension of the class II receiver is 2 inches, therefore the bottom of the receiver will be approximately 2-1/2 inches below the bottom of the fascia. To determine...
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  • Trailer Hitch Recommendation for 2019 Mitsubishi Outlander Sport
    Yes, the Curt hitch part # C13079 is a confirmed fit for your 2019 Mitsubishi Outlander Sport and would work well as it's a 2 inch hitch with plenty of towing capacity. If you have LED taillights the trailer wiring kit you need is the part # 118538. If you wanted to do some towing you might be interested in etrailer ball mount kit # 989900. It comes with 2 ball mounts; one with a 3/4 inch rise or 2 inch drop and one with a 2-3/4 inch rise or 4 inch drop. It also includes a 1-7/8 inch...
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  • Will Curt Hitch for 2011 Mitsubishi Outlander Sport Work For Towing
    The Curt Trailer Hitch Receiver part # C13079 is indeed a fit for a 2011 Mitsubishi Outlander Sport and offers a 3,500 lbs towing capacity though keep in mind you will be limited by the vehicle if lower. In order to complete your setup you'll need the following: etrailer Ball Mount Kit for 2" Hitches part # 989900 T-One Vehicle Wiring Harness part # 118538 (LED Taillights) or part # 119147KIT (No LED Taillights)
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  • Recommended Trailer Hitch And Trailer Wiring For 2013 Mitsubishi Lancer Hatchback
    The trailer hitch I recommend for your Lancer is the Curt Trailer Hitch, part # C11479. This is a Class l hitch and it has a 1-1/4 inch receiver opening. The shipping weight of this hitch is 20 lbs. This trailer hitch measures 40-3/4 inches long, 19-1/2 inches wide, and 6-1/2 inches tall. Per Curt a stabilizing strap like part # 18050 is required for all non trailer loads or it will void the warranty. The ball mount I recommend is the Sportframe, part # 3592. This ball mount features...
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  • Recommended Vehicle Wiring for Trailer Connection on 2013 Outlander Sport
    For your 2013 Mitsubishi Outlander Sport the wiring kit you need is dependent on whether your tail lights have light bulbs or if it has a bunch of the little bubble/small dot lights. If you have the large bulb lights, then you will want the Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector # C59236. If you have a bunch of the small dot style lights, then you will want the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118538. If you cannot...
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  • Recommended Trailer Hitch For 2017 Mitsubishi Outlander Sport
    It looks like you are interested in the Curt trailer hitch # C13079 for your 2017 Outlander Sport. This is a Class lll hitch and it has a 2-inch receiver opening. Per Curt, all non-trailer loads (bike racks, cargo carriers, etc) must be supported by stabilizing straps, such as part # 18050. For that reason I recommend the Draw-Tite Max-Frame # 76098. This is also a Class lll hitch with a 2-inch receiver. If you plan on doing some towing you might be interested in etrailer ball mount...
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  • Parts to Add 7-Way to 2019 Mitsubishi Outlander Sport for Brake Controller
    So there isn't a plug-in option for a 7-way for your 2019 Mitsubishi Outlander Sport, which means to add a 7-way you will need to start with a 4-way connector and then add the 7-way adapter to utilize a brake controller. Here are the parts you'll need for this, and please note the correct 4-way for your '19 Outlander Sport will depend on if you have LED taillights or not. - With LED Taillights: T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118538 - Without LED Taillights:...
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  • Best Trailer Wiring Harness for 2017 Mitsubishi Lancer
    All the trailer wiring harnesses we offer for the 2017 Mitsubishi Lancer would install in the same manner. The harnesses would all connect inline at the connection of the vehicle's taillight harness and the taillight assemblies. You'd then need to run a wire under the vehicle to the positive battery terminal to power the trailer lights. I'd recommend the Tekonsha # 118538, as I've found over the years that their taillight converter/trailer wiring harnesses work the best with the fewest...
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  • Recommended Trailer Hitch Receiver and Other Parts to Tow with a 2016 Mitsubishi Outlander Sport
    The trailer hitch receiver I recommend for your 2016 Mitsubishi Outlander Sport is the Draw-Tite # 76098. This is a Class III hitch with a 2 inch receiver opening. I suggest the Draw-Tite over the Curt because the Curt requires you use Support Strap # 18050 if you're carrying a non-trailer load, like the bike rack. Also, a Class III hitch receiver has a 2 inch opening. The 2 inch accepts a larger variety of bike racks and other accessories than a 1-1/4 inch will. If it turns out you...
    view full answer...

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