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  1. Custom Fit Vehicle Wiring
  2. Mazda
  3. CX-9
  4. 2018
  5. Tekonsha
FITS 2018 Mazda CX-9
T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector
Tekonsha

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

Part Number: 118278
In Stock
$54.86
Retail:$79.32
You Save: 31%
Custom Fit Vehicle Wiring
Confirmed to Fit
2018 Mazda CX-9

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The best technical support and full custom fit vehicle wiring installation instructions. Great price CX-9 custom fit vehicle wiring and expert service. Mazda CX-9, 2018 custom fit vehicle wiring by Tekonsha are available from etrailer.com. For expert service call 1-800-940-8924 to order your T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector part number 118278, or order online at etrailer.com.
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  • Reviews (157)
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2018 Mazda CX-9 - T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector

Highlights

  • Quick and easy installation: The T-One connector plugs into the OEM tow package harness.
  • ModuLite power module: Converts brake and turn signals for trailer compatibility.
  • Corrosion prevention: Use a small amount of grease on electric connections.
  • Powered directly from battery: Avoids overloading the vehicle’s electrical system.
  • Custom Fit: Designed specifically for Mazda CX-9 models from 2016 onwards.
  • 4-Way flat trailer connector: Supports multiple trailer light functions seamlessly.

Features to know about

Effortless Installation: Plug-and-Play Wiring Harness

Installing trailer wiring can often be a daunting task, but the T-One Vehicle Wiring Harness from Tekonsha makes it a breeze with its plug-and-play design. No need for cutting, splicing, or tapping into your vehicle's wires. Just plug the T-One connector directly into your Mazda CX-9's factory tow package harness found in the rear cargo area. In less than 20 minutes, you'll have a fully functional 4-way flat trailer connector, ready to power your trailer's signal lights.

Reliable Signal Conversion: ModuLite Powered Converter

Running into compatibility issues between your vehicle's wiring system and your trailer? The built-in ModuLite powered converter seamlessly transforms your car's separate brake and turn signals into a two-wire system that trailers use. This means your trailer's lights operate properly without straining your vehicle’s electrical system. Enjoy the peace of mind that comes with knowing your lights are powered correctly without overloading your circuits.

Tailored Fit Just for You: Custom Fit for Mazda CX-9

Frustrated with products that claim to fit a wide range of models but end up being a compromise? This T-One harness is specifically designed for the Mazda CX-9, ensuring a perfect match and easy installation. Whether you own a 2016 or a 2023 model, each component is crafted to fit seamlessly and function flawlessly, reducing installation time and potential confusion.

Secure and Weather-Proof Connections: Prevents Corrosion

Trailer wiring should last through all kinds of weather and terrain, and corrosion can be a major concern. This T-One wiring harness recommends using a small amount of dielectric grease on all electrical connections, including the 4-pole connector. This simple measure significantly protects the wiring from moisture and corrosion, extending the life and reliability of your connections.

Versatile Compatibility: Works with Multiple Pole Adapters

Need to connect to different trailer types? The T-One Vehicle Wiring Harness is compatible with 5-pole, 6-pole, and 7-pole adapters (sold separately), offering flexibility in towing various trailer setups. Whatever your towing needs, this harness can adapt to keep you connected and on the go.

Seamless Integration: Factory Tow Ready

Concerned about disrupting your car's design? Mazda CX-9 vehicles often come pre-equipped with a trailer-ready connector, meaning little to no modification is required for hitching up your trailer. This harness effortlessly integrates with your car's existing features, maintaining the vehicle’s aesthetic while adding functionality.

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

Installation Details 118278 Installation instructions

California residents: click here


Customer Satisfaction Score:

Ratings & Reviews

4.9

157 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 MazdaCX-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 profile picture

Jon

1/29/2024

Works perfectly! No issues with it



by:

Fast shipping. Exactly as listed. Easy direct installation. Perfect plug and play wiring harness. Thx.



by:

Easy installation and great video on website for help



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 profile picture

Ca

5/2/2024

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



by:
2021 MazdaCX-9

Electric cable install was pretty easy. Make sure that you have a set of plastic rivet removers. The kit is completely plug and play very easy to install with the Mazda CX-9. Make sure you have a little little silicone when dropping the cables through the rear light.



by:

Great customer service. I told William what I was going to be pulling he made sure I had everything I needed. Easy to install just watch the video had it completed in about one hour. Thanks again William



by:
2016 MazdaCX-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:
2021 MazdaCX-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:
2016 MazdaCX-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:

I'm very satisfied with your time and promise great



by:

Great product simple to install, I also like your follow up!!’



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:

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:

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’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:

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:
2016 MazdaCX-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. profile picture

R. U.

10/4/2018

Awesome thank you!



by:
2016 MazdaCX-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. profile picture

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:

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:

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



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:
2018MazdaCX-9

Straightforward installation with the etrailer video. Nice quality harness. Plug and play simplicity.

Thrones profile picture

Thrones

3/26/2020

Working flawlessly after a year.



by:
2019 MazdaCX-9

This kit installed seamlessly on our 2019 Mazda CX-9. The instructional video from etrailer perfectly walked me through step-by-step which was very reassuring, since I'd probably have been a LOT more delicate removing the necessary side panels in the back of the SUV without it. Just like the trailer hitch I purchased, the instructions were spot-on and made installation of this wiring harness an absolute breeze. etrailer has definitely set the bar on installation and support for their products.



by:
2016 MazdaCX-9

I purchased the wiring harness and drawtite class III receiver trailer hitch for a 2016 Mazda CX-9. These are detailed instructions that are missing from the pkg. Wiring harness requires removal of some of the rear back bottom and passenger side cargo inside panels. A couple bolt screws that hold the strap and cargo nets and the clips that require you to pressure the panel out or upward. Plug in and screw grd strap, route cable to rear bottom where the spare is housed. I used one of the black rubber grommets in bottom of the trunk and sliced a hole to allow the trailer hookup plug to be near the trailer hitch. I sealed the grommet with clear silicone.
The trailer hitch bolts are easily installed using the wire fish bolt method that is provided. You screw the wire on to the bolt and thread the rectangular washer onto the wire and feed thru the back larger hole to the front hole then holding the wire, insert the bolt and washer up thru the back hole and guide the bolt thru e washer and back down so threads are showing. I used a floor jack to support the muffler system. You have to drop it to install the hitch. Four hands to bolt up hitch would make if easier. Hope this helps.
Great product and price.


25
157
Show More Reviews

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

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  • Hands Free Lift Gate Disabled with Hitch Install on 2020 Mazda CX-9 Grand Touring?
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  • How To Power Curt Echo Mobile Brake Controller on 2019 Mazda CX-9
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