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 # 118497
lowest price pledge
Our Price: $58.48
You Save: 49%
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.

Orders above $99 qualify for Free Shipping
Shipping Weight: 1.7 lbs
In Stock
118497 - Powered Converter Tekonsha Custom Fit Vehicle Wiring
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

In Use/Installed

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. 1-800-940-8924 to order Tekonsha custom fit vehicle wiring part number 118497 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 (5)
  • Q & A (0)
  • Videos (3)
  • Photos
  • Why etrailer?

Tekonsha Custom Fit Vehicle Wiring - 118497

  • 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 within your trunk or rear 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.

118497 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite

Installation Details 118497 Installation instructions

This Product Fits The Following Vehicles

California residents: click here

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

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Trailer Wiring Harness Installation - 2012 Buick LaCrosse

Today on our 2012 Buick Lacrosse, we'll be installing the Tow Ready T1 Connector, part number 118497. First, we'll open up the rear cargo door on our trunk and then we'll need to access the wiring behind the tail lights. To access the tail lights, we'll first remove the spare tire cover and rear threshold. To remove the rear threshold, we'll gently pry out on the bottom and then pull up, popping all the fasteners free from the sheet metal. Next, we'll go ahead and remove the pushpin fasteners securing the carpet behind the tail lights. Now, we can pull the carpet away.

You can see we can access the four fasteners securing the tail lights into position. We'll go ahead and remove the plastic wing nut fasteners, then we can pop the tail light free. Next, we'll press on the locking tab for the tail light wiring and remove it, setting the tail light aside. Now, we'll need to run the brown and yellow wire connector out. We'll use the manufacturer's grommet.

We'll push the grommet out of its position and use a pair of side cutters to cut a slice in the grommet. We'll run the wire through the hole and then through the slice in the grommet, reinstalling the grommet. Now, we can go ahead and connect it to the manufacturer's wire and the other end to the tail light assembly plugging in line with the manufacturer's wiring. Now, we'll go ahead and reinstall the driver's side tail light assembly. Next, we'll go ahead and take the white wire coming from our converter box with a pre-attached ring terminal.

We can attach it here to the manufacturer's ground stud. We'll go ahead and remove the stud, securing the stud. Install the ring terminal and then re-secure the ground stud nut. Now, we can go ahead and take the red and green wire connector and route it over the passenger's side, repeating the same process of removing the carpeting and tail light assembly, routing the wire out to the grommet plugging in line with the manufacturer's wiring. Now, we'll go ahead and take a black zip tie and secure the wire to the manufacturer's wiring.

Next, we'll take the red wire from our converter box and attach a yellow butt connector. Then we can take the black wire from our install kit. Strip back one end and attach it to the butt connector. This will be the power wire that we'll be running to the engine compartment and attaching to the battery. I recommend to wrap up this butt connector connection as it will assist in keeping out moisture, dirt and debris that can build up over time. To get our power wire routed outside the vehicle, we'll go ahead and use the manufacturer's grommet here in the center near the spare tire well. We'll go ahead and take a utility knife, cut a slice in the grommet and then feed our wire through and pull the excess wire underneath the vehicle. Now with all our wires run, we can go ahead and peel back the two-way adhesive on our converter box and attach it to a clean flat surface. Here behind and below the driver's tail light assembly is the perfect location. Now with our wires run, we'll go ahead and use some of the black zip ties provided with our install kit to secure our wiring. To clean up our install look, we'll go ahead and trim off the excess from our zip ties. Now, we can go ahead and reinstall the interior trim components here in the trunk. Next, we'll start routing our power wire up to the engine compartment. Keep in mind when routing your wire to stay away from excessive heat such as exhaust or moving components such as steering or suspension. As we route our wire, we'll also secure it with a black zip tie. Now that we've got our wire routed up into the engine compartment, we'll go ahead and take a black zip tie and secure it. Next, we'll go ahead and remove battery cover and terminal cover so we can access the positive battery terminal post. As you can see, there is a positive battery terminal post and stud that we can attach our ring terminal to. However, the nut on this post is not designed to be removed but only loosen. Next, we'll go ahead and prep our fuse holder to prepare to add it to our power wire. Cut the fuse holder in half and strip back both sides. We'll add a butt connector to one end and ring terminal to the other and then we can go ahead and cut off the excess from our power wire and attach the yellow butt connector. A quick tech tip: I recommend going ahead and take some black electrical tape and wrap up the butt connector connection. This will help to keep out dirt, dust, debris and moisture. For this application, the positive battery post nut is not designed to be completely removed but only loosen. We'll go ahead and take a pair of side cutters and cut a small slit into the ring terminal and feed it over the stud. Now, we'll go ahead and secure it with the stud nut. Now with our power wire attached, we can go ahead and reinstall the battery terminal cover and secure our wiring. Now, we can go ahead and install the fuse in the fuse holder and cover with the cap. Next, we'll go ahead and cut off any excess from our zip ties and then reinstall the battery cover. Now with everything reinstalled, let's go ahead and show you how to use your new 4-pole connector. We'll simply take it out of the spare tire well and drape it out over the trunk threshold. Be careful to stay away from the latch as pinching off in the latch can harm the wire. However, the weather stripping is thick enough that it won't simply close the trunk on the wire. Then once we're finished using our new 4-pole connector, we'll go ahead and wrap it up and store it down with the spare tire. That will complete the install of our new Tow Ready T1 connector, part number 118497, on our 2012 Buick Lacrosse.

Customer Reviews

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118497

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


I’ve never done this type of install before. With this in mind, and, help from my brother Inlaw, the product here works very well. Smile face here!
Thank you very much

Continued success with this product keeps me smiling. I’m completely satisfied with having my wife smiling also, It’s her stuff, I just installed it.
David W - 07/09/2022

2013 Chevrolet Silverado 1500

The unit was installed in about 2 hrs. I used 2 drive on wheel lifts and a creeper. The unit is installed on a 2013 Buick and I have a 1500 cap. trailer. I also installed a light system that is problem free.

2014 Buick LaCrosse

I bought a hitch kit and the wiring conversation kit and was very pleased with both. They arrived sooner than estimated and were easy to install. The video instructions provided were extremely helpful too. Thank you etrailer!


Works great. Not too bad to install.


Works as it shoukd.


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

  • Tips for Routing a Power Wire from the Battery to Trunk for Trailer Wiring on a 2011 Buick Lacrosse
    There are a few methods that people use when they need to run a power wire from the vehicle battery to the rear of the vehicle. One method involves routing the wire as much as possible through the frame. What you would need to do first is determine if the frame has a hole in which a wire can be run and if there is space enough for it. You would need a long rigid and skinny object, like a coat hanger to run through the frame, tie off the wire to it, and then pull it back through. This...
    view full answer...
  • Trailer Hitch Receiver for a 2015 Buick Lacrosse FWD
    The Draw-Tite Class II # 36538 or Curt # C12115 are a custom fit for your 2015 Buick Lacrosse FWD. The specific Draw-Tite hitch receiver you referenced will not fit your 2015 Buick Lacrosse FWD. With either option, if you will be towing a trailer you will additionally need a ball mount. I recommend # 36061 which comes with the pin and clip. You will still need a hitch ball like # 19258 for a 2 inch coupler or # 19257 for a 1-7/8 inch coupler. Then the wiring you will need for your hitch...
    view full answer...
  • Trailer Hitch and Wiring for a 2011 Buick LaCrosse CXL
    Curt trailer hitch # C12115 has a capacity of 3,500 pounds gross trailer weight and 350 pounds tongue weight. But I checked the owner's manual online for your 2011 Buick LaCrosse and found that it has a towing capacity of 1,000 pounds so you are limited to that even though the hitch is rated higher. If the gross trailer weight is under 1,000 pounds then you can pull it with your LaCrosse. A 17 foot boat and trailer is likely heavier than that though. The recommended ball mount for this...
    view full answer...
  • Trailer Hitch and Bike Rack Recommendations for a 2011 Buick Lacrosse CXS
    Some companies prefer to be more cautious with their product ratings than others. Curt requires the use of stabilization straps, # 18050, on all of their Class I and II trailer hitches, regardless of tongue weight capacity, in accordance with their warranty requirements. The Draw-Tite and Hidden Hitch trailer hitches do not require a strap, but a strap can still be used and would not be a bad idea in any application using a larger bike rack. I would recommend the Curt Trailer Hitch, #...
    view full answer...
  • Curt Trailer Hitch Receiver Compatibility With a 2015 Buick LaCrosse With Dual Exhaust
    You will not have any issues mounting the Curt Trailer Hitch Receiver # C12115 on your 2015 Buick LaCrosse with the dual exhaust. Since this receiver fits a large selection of Buick, Chevrolet and Cadillac vehicles the installation notes will cover all the different vehicles but some steps like lowering the exhaust will not always be necessary. For your LaCrosse I do not see any need to lower the exhaust. Curt recommends using their Cam Buckle Stabilizing Strap # 18050 for any hitch mounted...
    view full answer...

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

  • Why

    At we guarantee:
  • Highest quality custom fit vehicle wiring for the best price.

    Our Lowest Price Pledge ensures you will never overpay for the parts you need.
  • 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 Joshua S
Video Edited:
Joshua S
Employee Nicholas E
Test Fit:
Nicholas E
Employee Randy B
Test Fit:
Randy B
Employee Brent H
Test Fit:
Brent H
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 Zach D
Video by:
Zach D

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.