bing tracking image
  1. Custom Fit Vehicle Wiring
  2. Tekonsha
  3. Custom Fit
  4. Trailer Hitch Wiring
  5. 4 Flat
  6. Powered Converter
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

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

Item # 118548
Our Price: $66.58
You Save: 34%
Custom Fit Vehicle Wiring

Will this fit?

To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.

This item qualifies for Free Shipping
Shipping Weight: 1.64 lbs
In Stock
Tekonsha Trailer Hitch Wiring - 118548
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

Need help with installation?
Locate installers near me
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 118548 or order online at Free expert support on all Tekonsha products. Guaranteed Lowest Price and Fastest Shipping for T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
  • All Info
  • Reviews (34)
  • Q & A (0)
  • Photos
  • Why etrailer?

Tekonsha Custom Fit Vehicle Wiring - 118548

  • 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 in trunk
    • 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 inside your trunk, behind the tail lights on both the driver's side and passenger's side. You will need to remove some interior trim or carpeting to access the harness. 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 within your trunk.

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.

118548 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite

Installation Details 118548 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 - 118548

Average Customer Rating:  4.8 out of 5 stars   (34 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.

2015 Ford Focus

Easy to install, except the line to battery. Took about 15 minutes to find a good path. Use it to tow a jonboat with 6 hp motor on ford focus.

Still working with no issues. Still tow the jonboat and noe a log splitter.
John - 05/17/2022


I mean the product does what it’s supposed to do, it gives you trailer lights. As far as installing the product it takes some time, especially if you don’t have a floor jack to really get up under the car, took about 2 hours to really get everything ran and tucked away neatly. Happy with it.


Super easy to install with the plug and play connectors, and that the car manufacturer designed it into the wire harness for install. Was done in about 30 mins. Would definitely buy it again.


I had a professional install the wiring, then I pulled my home-made camper from Ohio to New Orleans and back. I could not be happier with how everything worked.

2014 Ford Focus

It works. What else could you want. I ended up using an add a circuit to the fuse box in the luggage compartment for power. It's fuse F9 25amp for anyone wondering(add a circuit let's you put a different fuse in for the circuit your adding, I used a 10amp for this harness) It's for power driver seat which my se model doesn't have. Thiers also a factory ground 6 inches away that you can use to ground. Only thing is I wish the 4 pole connector had a bit more length. A foot more would have been perfect to not have any sketch factor when backing the trailer sharply. Also I soldered the splice because butt connectors work fine but they do fail and I don't want to Lose any of my lights and get rear-ended. Just more reliable.


This is the second trailer hitch I've bought from and they've done a great job both times. Thank you Josh for expediting my order!!!

Ford Focus

Great product... Installed in less than an hour. Hint: Dont folliw directions and run power wiire from your ford focus trunk to your battery. There is a perfectly fine connection for power on the left side of the trunk. Its a small fuse block with plenty of unused power ports. Been installed over a year and no problems. Recommended!!

2015 Ford Focus

Product works just like supposed to. Be careful taking off left lower trim piece. There is a holder about half way on the top that needs pulled out before complete removal. I broke mine and had to use carpet tape to adhere it back. Other than that take your time, remove pins from left rocker trim and feed it through and up to engine compartment. About 2 hours and two man job.

2012 Ford Focus

I was shocked when my order arrived in 2 days! Well boxed and exactly as ordered. The Draw-Tite sport fits cleanly between bumper and muffler, only the receiver is visible. Hitch and wire harness installed in 1.5 hours.


Very easy to install due to simple instructions! Harness made hiding wires in the trunk a breeze! Took about an hour and a half to get everything done only because I spent a lot of time hiding the wiring the way I wanted.


Fantastic company. Alex J was a pleasure to work with. He kept me informed even after I ordered incorrect parts. I will use them again and will suggest others do the same. Etrailer has made a customer for life. Thank you Alex

2012 Ford Focus

This is a product that is really plug in simple. I watched etrailer's video for my model and had no issues. The only way it would have been easier is if I had a lift. Other than that great product.


This wiring kit was way to easy to hook up! The only problem I had was what to do with all the extra time left from what I had allotted myself to get this completed

2012 Ford Focus

The receiver was as described and
instructions were good except
for the cutting of the insulating plastic and its purpose


Very easy to install, The instructions in the videos are very clear and easy to follow..I would definitely buy and recommend this site to anyone.

2012 Ford Focus

These new connector kits use separate power sources unlike the old ones, so you need to fish the power line up to the battery. It's a tougher job than it used to be to install one, therefore. However, I recognize that a separate power source will make the system more reliable and less prone to blow fuses in the taillight circuit like the old ones occasionally did.

2012 Ford Focus

Product worked great. I can't say how easy or hard it was to install because I had a mechanic do it for me. I had ordered the wrong version initially but Kelly in customer service helped get me the right product and had it overnighted to me because I needed it in a hurry. Great service and a product that worked well.


Works great. Instructions were spot on.


Unit did not work as it should. If I got one side to the would fail.
Took unit out of the car and dumbed it.
Very disappointed with this product.


The product was fine. The installation was a challenge. Not due to the product, but to the vehicle.

2017 Ford Focus

Great product, but you need to run a power line from the back of your car to the front of your car and connected to the battery. They do not tell you this in the description. Works well recommended

There is a bullet poi in the feature of our product description that indicates to run a hot lead to the battery. We do also have a help article that explains the steps on how to do this for your reference.
-- Etrailer Expert Rachael H - 07/31/2019

2016 Ford Focus

Zero problems, simple instructions that are easy to understand.

2015 Ford Focus

awesome hitch and wiring harness!!!!!! very satisfied!!!!!!!
CARL J - 04/08/2022

2013 Ford Focus

Great product. Easy install with excellent fitment. Sales personnel were very helpful and keep me informed of shipment status.


Easy to install. No issues so far

Show More Reviews

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

  • Correct T-One Wiring Kit for 2013 Ford Focus Sedan and Hatchback Models
    If your 2013 Ford Focus is a Sedan you need the T-One # 118548 but if your Focus is a Hatchback you need the T-One # 118549 instead. Both options tee in behind the tail lights of the vehicle and pull power directly from the battery via the included lead but the difference is the connectors that tee in. The Sedan and Hatchback models use different connectors for the tail lights for the OEM wiring so it is important to make sure you get the correct kit.
    view full answer...
  • Trailer Running Lights Lit All the Time w/Curt Trailer Wiring Harness Installed in 2013 Ford Focus
    Does your trailer happen to have LED lights? If so then what is happening is the little bit of power that is on wiring harness # C56138 is enough to dimly light up LED lights. This is because the wiring harness is a powered harness and LED lights draw such little power. We hear about this issue less with the Tekonsha harness # 118548. It is also possible that there is a short drawing power. Make sure the trailer connectors are clean and free of corrosion. Also check the wiring on the trailer...
    view full answer...
  • Tow Bar Wiring Recommendation for a 2015 Ford Focus
    Sounds like you are actually looking for tow bar wiring and not trailer wiring for your 2015 Ford Focus like the part # 118548 that you referenced. For lighting you can use the diode kit, # RM-15267, and not have to worry about cutting into the taillight housing. This will splice into your taillight wiring to allow your tow vehicle to control the taillight assemblies of the towed vehicle. This comes with a round 6-way connector that you will install on the front of your towed vehicle and...
    view full answer...
  • Towing Motorcycles with a 2014 Ford Focus
    I checked your owner's manual and it states the following: WARNING: Never tow a trailer with this vehicle. Your vehicle is not equipped to tow. No towing packages are available through an authorized dealer. We don't recommend going against what the manufacture says but if you decide to tow your motorcycles anyways here are the parts you will need. The custom fit hitch for your 2014 Ford Focus is # 24872, in addition to the hitch you will need a ball mount and a ball to tow the trailer...
    view full answer...
  • Trailer Hitch Recommendation for a 2014 Ford Focus
    The Draw-Tite Trailer Hitch # 24872 that you referenced would be an excellent choice for your 2014 Ford Focus. This hitch has been confirmed to fit your Sedan Focus and should work very well for you. I attached installation instructions and an install video for this product for you to check out also. If you plan on doing some towing you may also be interested in purchasing the following products to complete your towing setup: Tow Ready Custom Fit Vehicle Wiring # 118548 Draw Tite Ball...
    view full answer...
  • Trailer Wiring 4-Way Harness Recommendation for a 2014 Ford Focus
    The Tow Ready Custom Fit Vehicle Wiring # 118548 that you referenced can install on your 2014 Ford Focus without voiding the warranty of the vehicle. The connectors will plug inline with the taillight harness of your vehicle and will provide you with a 4-way for trailer taillights. I attached a set of installation instructions to the right for you to check out as well. For a hitch I would recommend the Draw Tite Hitch part # 24872, ball mount # 3593, 1-7/8 inch ball # 19256, 2 inch ball...
    view full answer...
  • Hitch Recommendation for a 2014 Ford Focus to Tow Small Trailer
    We have everything you need so that your 2014 Ford Focus can tow a trailer. For a hitch I would recommend the Draw-Tite part # 24872 as it has been confirmed to fit your vehicle. You will need ball mount number 3593. I attached an install video for you to check as well. You will also need a hitch ball to complete the connection. For that you would want the part # 19256 for a 1-7/8 inch hitch ball or part # 19258 for a 2 inch hitch ball. For trailer wiring you would want part # 118548....
    view full answer...
  • Trailer Hitch Recommendation for 2012 Ford Focus for Towing Trailer
    I wish we had a carrier solution that I could recommend, but all of the hitches for your 2012 Ford Focus like the Draw Tite # 24872 do not have the capacity for a scooter carrier like you'd need. Only possible solution would be a trailer for the scooter with the hitch. For trailer wiring you'd want the part # 118549 for if you have a hatchback or part # 118548 for if you have a sedan. For a ball mount you'd then want the part # 3593 and hitch ball # 19256.
    view full answer...
  • Hitch Fits for 2015 Ford Focus 5-Door Hatchback
    If you wish to install one of the available light-duty Class I hitches you can refer to the linked page. Use the "Select Vehicle Style" drop-down menu tool to select your hatchback version to then see compatible hitches. Draw-Tite 1-1/4-inch Class I hitch # 24872 fits the sedan version as well as the S, SE and Titanium Hatchback models. For 4-pole wiring you can use # 118548 and for a ball mount part # 3593. You would also need a hitch ball like 1-7/8-inch # 19256 or 2-inch # 19258. The...
    view full answer...
  • Recommended Trailer Hitch Receiver and Trailer Wiring Harness for 2012 Ford Focus SE
    For your 2012 Ford Focus SE, I recommend the Draw-Tite Sportframe Trailer Hitch Receiver - Class I - 1-1/4" # 24872. This is a custom fit for both the sedan and hatchback as they install the same way and I've attached a video to assist. This is a no drill installation but the heat shield underneath will need to be trimmed for fit. For your wiring, I recommend the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118548. This will install behind your tail lights...
    view full answer...
  • Trailer Hitch and Towing Setup Recommendation for a 2014 Ford Focus SE
    Grab your owners manual for your 2014 Ford Focus and it will have the towing capacities/restrictions for the vehicle listed there. The # 24872 hitch that you referenced has been confirmed as a fit for your 2014 Ford Focus and has a 2,000 lb trailer towing capacity. But that doesn't necessarily mean your vehicle has the same capacity. Overall towing capacities are only as strong as the weakest component. So you would need to go with the lowest rated component as an overall capacity. For...
    view full answer...
  • Parts Needed to Tow a Trailer with a 2014 Ford Focus
    During my research for your vehicle, I found that in the owner's manual it states that you should never tow a trailer page #202. This means that the hitch is intended to transport items like a bike rack or cargo carrier. See page #195 for more information about this. If you decide to tow anyways you will need a hitch, wiring, a ball mount, and ball to tow a trailer. The Draw-Tite hitch # 24872, you were looking at will be a fit for your 2014 Ford Focus. There are ball mounts like #...
    view full answer...
  • Hitch and Trailer Wiring Fit for a 2016 Ford Focus
    For your 2016 Ford Focus there are only Class I hitches available like the part # 24872 which would not have the needed capacity to carry a wheelchair/scooter carrier. You could use a small trailer with this hitch if you had to find a way to use this vehicle for transporting the chair though. You would need the ball mount # 3593, ball mount # 19258 for a 2 inch ball, # 19256 for a 1-7/8 inch ball, and for trailer wiring part # 118548.
    view full answer...
  • Trailer Hitch and Towing Components Needed for 2014 Ford Focus
    The towing capacities of a vehicle are typically very conservatively figured so as long as you are staying under the capacity of your 2014 Ford Focus you'd be totally fine. For your 2014 Ford Focus the Draw Tite hitch part # 24872 would be the hitch to go with. This fits sedans and hatchback models too. For trailer wiring you'd then want the part # 118549 for if you have a hatchback or part # 118548 for if you have a sedan. Tekonsha wiring kits are the most reliable so they are what we...
    view full answer...
  • Hitch Recommendation for a 2014 Ford Focus Sedan
    Since you plan on towing a small trailer you will want a draw bar so the Draw-Tite part # 24872 would be your best choice. You will need drawbar number 3593. The drawbar will insert into the hitch and will provide the attachment point for the hitch to the trailer. You will also need a hitch ball to complete the connection. For that you would want the part # 19256 for a 1-7/8 inch hitch ball or part # 19258 for a 2 inch hitch ball. For trailer wiring you would want part # 118548. I attached...
    view full answer...
  • Installing Brake Controller and 7-way Trailer Connector on 2014 Ford Focus
    If your trailer has electric brakes and a 6-or7-way trailer connector, you'll need to install a brake controller on your vehicle to actuate the trailer brakes. Before attempting to tow your trailer, I'd recommend you determine the fully loaded weight of your trailer, and ensure it doesn't exceed the towing capacity of your Focus. If your trailer weighs less than the towing capacity of the vehicle, you'd begin by choosing a brake controller. The Tekonsha Primus, part # TK90160 is a reasonably-priced...
    view full answer...
    Image 1 for
  • Installing a Trailer Wiring Harness on a 2012 Ford Focus
    It depends on what wiring harness you are using on your 2012 Ford Focus. If you are using a hardwire harness where you have to find and splice in the wires from the harness to the tail light wiring on the vehicle, you will need to use a circuit tester to find the correct wires on the vehicle. If you do not have a circuit tester you can use # PTW2993. Have someone sit in the vehicle and go through the lighting functions; turn signals, running lights, and brake lights, while you test the...
    view full answer...
  • Recommended Trailer Hitch Receiver for 2017 Ford Focus Sedan S Model
    The Curt Trailer Hitch Receiver - Custom Fit - Class I - 1-1/4" # C11158 and the Draw-Tite Sportframe Trailer Hitch Receiver - Custom Fit - Class I - 1-1/4" # 24872 are confirmed to fit your 2017 Ford Focus Sedan regardless of model trim package. Class I trailer hitch receivers are always the 1-1/4 opening. Between these two options, I recommend the Draw-Tite simply because the Curt model requires use of a stabilization strap # 18050 for any non-trailer load like a bike rack or other...
    view full answer...
  • Hitch and Cargo Carrier Recommendation for a 2012 Ford Focus Sedan
    We have hitches that would work on your 2012 Ford Focus as well as cargo carriers, but the issue you will have is that no cargo carrier setup will allow you to carry more than 200 lbs of tongue weight on your vehicle. For a hitch you would want the Draw Tite Hitch part # 24872 and then for a cargo carrier you could use the Curt Carrier part # C18110. This carrier weighs 30 lbs so you would be left with 170 lbs of tongue weight left for cargo which may not be enough but aside from using...
    view full answer...
  • Can 6-Way Connector with Separate Brake Light and Turn Signal Circuits Install on 2013 Ford Focus
    A 6-Way round connector, especially one that has separate brake light and turn signal circuits, is rare which is why you can't find one. But I can tell you how to make your own 6-Way with separate brake/turn circuits. First, you could get some 6-Wire jacketed wire, # DW04906-1 sold by the foot, and a 6-Way round vehicle side connector such as # HM48420. Then you would use a circuit tester such as # 40376 to find the functions of the tail light wires on your 2013 Ford Focus. Once you have...
    view full answer...

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

  • Why

    At we guarantee:
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate custom fit vehicle wiring information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Need to return an item? No problem. Please read our Returns Policy for more information.

Info for this part was:

Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Kathleen M
Video by:
Kathleen M
Employee Laura H
Updated by:
Laura H
Employee Wilson B
Updated by:
Wilson B
Employee Alexander C
Updated by:
Alexander C
Employee Isabelle B
Updated by:
Isabelle B
Employee Chris R
Video Edited:
Chris R
Employee Shane H
Test Fit:
Shane H

At we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.