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  1. Custom Fit Vehicle Wiring
  2. Tekonsha
  3. Custom Fit
  4. 4 Flat
  5. Trailer Hitch Wiring
  6. Powered Converter
T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector

T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector

Item # 118278
Retail:$92.72
Our Price: $50.91
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Custom Fit Vehicle Wiring

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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 OEM tow package harness - no cutting, splicing or tapping required. 1-800-940-8924 to order Tekonsha custom fit vehicle wiring part number 118278 or order online at etrailer.com. Free expert support on all Tekonsha products. Great prices and Fastest Shipping for T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
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  • Reviews (147)
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Tekonsha Custom Fit Vehicle Wiring - 118278

  • Custom Fit
  • 4 Flat
  • Trailer Hitch Wiring
  • Tekonsha
  • Powered Converter

Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into OEM tow package harness - no cutting, splicing or tapping required.


Features:

  • Provides a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights
    • Designed for use with a factory tow package
    • Compatible with 5-pole, 6-pole, and 7-pole adapters (sold separately)
  • Connects quickly and easily - no cutting or splicing of wires
    • Locate connection points in rear cargo area
    • Plug in T-connector
  • 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
  • 1-Year limited warranty


Installation

This custom-fit T-One connector plugs into your vehicle's factory tow package wiring harness, which is located in your rear cargo area. You will have to remove the rear threshold plate and interior paneling to access this harness.


Once installation is complete, the 4-way connector will be stowed beneath your vehicle, near the trailer hitch. A mounting bracket (sold separately) is recommended to keep the connector secure.


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.



118278 Tekonsha T-1 T-Connector - OE Replacement - 4-Way

Installation Details 118278 Installation instructions

This Product Fits The Following Vehicles



California residents: click here


Customer Satisfaction Score:


Customer Reviews

T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector - 118278

Average Customer Rating:  4.9 out of 5 stars   (147 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 OEM tow package harness - no cutting, splicing or tapping required.

by:
2023 Mazda CX-9

etrailer! Is the best when it comes to adding a tow hitch and wiring to your vehicle! Prices are superb and if you’re a diy’er it’s wonderful!

Jon

1/29/2024

Works perfectly! No issues with it



by:

I ordered this unit to install on a 2024 Mazda CX-9, to tow a small teardrop trailer, and it has worked very well. Installation was easy and took less than 2hours, taking your time. I really like that there are videos on etrailer’s web site to aid in the installation process. I did buy a class3 hitch with a 2inch receiver and a separate bracket for the four pole flat connector for this install. One year later, it’s still doing great.

Ca

5/2/2024

Still going strong. Correction: it is a 2023 year Model CX-9.



by:
2021 Mazda CX-9

Mazda made this install no fun at all, but the ETrailer installation video made this possible for me to do. I never would have found the trailer wiring plug without it. Only issue I have is the 4 pin did not come with a bracket to attach to the steel bracket on the hitch.



by:

I’ve installed three hitches and used several other etrailer products. Everything is of very high quality, fits well, and comes with thorough instructions. This wiring kit was easy to install and works perfectly.



by:

All products were delivered in a very timely manner. The folks at E trailer are all excellent folks that are pleasure to deal with. If they have the product you were looking for you’re crazy not to purchase from them price is very competitive, and the customer service is outstanding.



by:

Fast shipping. Everything you need included in package. Watch the videos online, it is that easy.



by:

Shawnee E was very helpful and knew just what I needed and offered a suggestion on a part I hadn't thought of. The order arrived within a few days, and the online videos offered by Etrailer made the installation very easy. I would definitely check with Etrailer for my next purchase of equipment.



by:

Purchased for use with 2021 CX-9 Grand Touring. Harness works for trailer lights but doesn't disengage SCBS so car auto brakes when reversing if you don't manually turn it off.



by:

Package and harness arrived as advertised . Installation was straight forward. Strongly advise on getting a helper. Installation will be faster. Fit and quality was excellent.



by:
2016 Mazda CX-9

If you have a 2016 MAZDA CX-9 - this kit WORKS. It appears all 2016 Mazda CX-9's have the trailer wiring harness already installed. It is located behind the rear passenger side interior panel - the Tekonsha instructions show you how to get to it.

You do NOT need to get a "generic" wiring kit as many of the other responses are suggesting. Just plug this one in and it works.

I have submitted pictures below of the installation on my vehicle. I also installed the 76020 Draw-Tite Class 3 Trailer Hitch Receiver which fit nicely.



by:

Simple and easy to install. Quality is exceptional.



by:

I guess I thought the hitch had a mounting bracket to mount the 4pin bracket to. No biggie, I just drilled a couple holes and mounted. Maybe I didn’t do right? Regardless, this will work. Thank you



by:

Easy to install and everything works as it should. Hauled a camper about 4 times with this harness installed. All lights still working good.



by:
2016 Mazda CX-9

Nice product and easy to install the "Draw-tite Max-frame Trailer Hitch Receiver" with T-One wiring harness for Factory Tow Package- 4 Pole Flat Trailer Connector...



by:

Bought this about a year ago. I installed it with very few tools by myself. Ive been using it to tow my 1996 21 ft bayliner trophy. This is a great product and i would recommend it a million times!!



by:
2019 Mazda CX-9

Super fast, next-day free shipping to Nashville TN! All of the parts look good.



by:

The hitch looks so nice and durable
They
shipped so fast And the price are fair
I will recommend to anyone who is looking for a great hitch



by:
2022 Mazda CX-9

This is the second time I have ordered a trailer hitch, wiring harness, and ball mount. Once again, the installation instructions, especially the videos, were excellent, and everything was a perfect fit for my vehicle. Thanks very much!



by:
2023 Mazda CX-9

This is my second time ordering from etrailer. Both orders shipped within 24-hours and were delivered 2-days later. Great service and great products.



by:

So far so good. Have yet to trailer anything. Wiring harness is pretty straight forward but takes a little patience taking off panels.



by:

I installed the hitch with out any problems. I still need tl install the wire harness.



by:
2016 Mazda CX-9

This is in reference to a 2016, Mazda CX9. This comment adds to the 2 previously posted comments. It deals with getting the interior panel to release. There are 2 screws that must be removed before attempting to remove the panel. One screw is at the top of the panel under the black plastic hook.The other screw is under a piece of plastic trim that must be removed where the lower chrome anchor is. Then remove the jack, and the other plastic parts near the jack. Once everything is removed, carefully start popping the trim panel off with a trim panel pry tool. Keep prying until you can reach the plug that part #118278 goes into.

Marty W.

10/7/2017

It is only a 4-wire harness. I really need a five wire for my boat trailer. I wish ETRAILER had a five-wire.



by:
2016 Mazda CX-9

The hitch receiver is easier to install than the wiring harness, but that is only because I hate taking apart all the snap fasteners on interior panels. But, once removed, this simply plugs in and you are good to go. Like in the video, I secured the ground on the 10mm bolt. One tip is to pull out the trays straight up and with some good force to pull out the white retaining pins. Otherwise, you will have to pry them out using a forked interior panel pry bar, like the one in the video. Overall, this is a great product.

R. U.

10/4/2018

Awesome thank you!



by:
Mazda

Would have liked a hole in Mazda big enough to accept a 4-plug since there was a place on the receiver to receive it and mount it.



by:

Website with installation videos and good quality materials is just great. Never a problem.


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Show More Reviews

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