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  1. Custom Fit Vehicle Wiring
  2. Tekonsha
  3. Custom Fit
  4. 4 Flat
  5. Trailer Hitch Wiring
  6. No Converter
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

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

Item # 118451
Retail:$62.18
Our Price: $52.05
You Save: 16%
Custom Fit Vehicle Wiring

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Tekonsha Custom Fit Vehicle Wiring - 118451
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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 - no cutting, splicing or tapping required. 1-800-940-8924 to order Tekonsha custom fit vehicle wiring part number 118451 or order online at etrailer.com. 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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Tekonsha Custom Fit Vehicle Wiring - 118451

  • Custom Fit
  • 4 Flat
  • Trailer Hitch Wiring
  • Tekonsha
  • No Converter

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 - 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
    • 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 behind tail lights
    • Plug in T-connector
  • Constructed of 16-gauge bonded wire
  • Comes with dust cap for 4-way flat connector


Specs:

  • Maximum amperage: 7.5 amps per circuit
  • 1-Year limited warranty


Installation

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 installation is complete, the 4-way flat 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.



118451 Tow Ready T-1 T-Connector - 4 Wire

Installation Details 118451 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 - 118451

Average Customer Rating:  4.9 out of 5 stars   (171 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 - no cutting, splicing or tapping required.

by:

Received product really quick package n icely



by:

The product was installed very easily and I have had no issues since installing it. Would purchase trailer supplies from here again.



by:

As always---prompt and courteous service followed by products that fit well. I don't know if the wiring harness works with a trailer, but I am confident it will. The hitch fit perfectly. Fast delivery.

John S.

9/29/2018

All is well with my harness and hitch after one year. No issues whatsoever.



by:
2011 GMC Acadia

The quick connects definitely helped reduce the time required to wire in the trailer light accessory. The quality of the product was top notch!

Ian M.

7/22/2016

I have only had to use it a couple of times but it works great and Im happy I made the investment. All parts are holding up well too!



by:
2010 GMC Acadia

I installed this on my 2010 Acadia. It fit perfectly and was easy to install.
The connectors are oem quality. The entire installation took about 1 hour.
Very satisfied.

Joe N.

7/25/2017

It still works just like it was brand new even after 1 year.No problems. Good product.



by:

Got my hitch very quickly even with the shipping delays going on with delivery services due to covid-19. As soon as the wiring kit was hooked up all the lights worked on the trailer without having to mess around with it. So far I am loving my purchase and wish I would have gotten one sooner.

According to my husband it was a very easy installation for both the wires and the hitch on my GMC Acadia.



by:
2012 GMC Acadia

I ordered a hidden hitch, wire assembly and mount for the four pole flat wire block that mounts onto hitch. The order was shipped together and arrived ahead of schedule. The hitch and wire assembly installed in a little more than an hour. Everything looks professional and factory. No issues with lights blowing fuses or any other concerns that I read. I will be recommending eTrailer to anyone who asks about my install.



by:
2012 GMC Acadia

Thank you so much. With the helpful videos and complete instructions the installation was a breeze. Both the hitch and light kit were a perfect match for my 2012 Arcadia. Sturgis here I come!
When I finished, my first thought was, "How easy was that!!"
I will have no problem recommending your site to anyone.
One note from my installation. The wiring and the plug ends fit through a space above the bumper support. With a little help from my pull wire, they ended up no where near the exhaust.
Thanks again,
Terry



by:

This is a high quality made wiring set. The price cannot be beat. Any local trailer store wants much more for a wire harness and it is not a complet ready to go set like this. It makes it so simple to plug into your existing tail lights and it is the perfect length to go from one side to the other and have a little bit extra for tucking and going around corners. I would highly recommed this.



by:
2009 GMC Acadia

I bought the T-One Vehicle Wring harness for my 2009 GMC Acadia. Installation was a breeze and the product works perfectly. After I received my harness I spent a few minutes reading the instructions and getting familiar with the parts. Within 20 minutes I had the harness completely installed and was ready to hook up my trailer and roll. I would highly recommend this to any one looking for an easy solution for adding a trailer lighting option to your vehicle!!



by:
2011 GMC Acadia

Recently installed the Draw Tite hitch and the wiring harness on my 2011 Acadia. Both units installed without a problem, it couldn't have been simpler. the only coment I have is that the hitch bolts to the frame were 18mm not 3/4 inch. The bolts to the cross member were 3/4. As mentioned in another review the wire ties could be longer, 11 inch worked pretty good. One addtional comment to future customers is to make sure to watch the videos, they're great.



by:

The etrailer products were very easy to install, in a matter of 30 minutes I had the hitch and wiring completely in place. The directions that were provided were very clear and the quality of product is great. Etrailer was very friendly and reliable, they even upgraded my shipping at no cost! I will certainly use etrailer again and will recommend them to anyone!



by:
2001 GMC Acadia

I used the trailer connector on my 2001 Acadia while pulling my motorcycle from NC to FL recently. The connector performed just as I thought it would even in the rain. I would suggest some type of case for the receptacle that attaches to the hitch. When the connector is not in use, the receptacle just hangs in the air (not pretty). Overall, installation was simple, trailer hook-up was easy, and I couldn't be happier.



by:

Very easy harness. It only took 1 hour to put on the hitch with the harness. If i can do it anyone can. Its so easy because its dummy proof, you really cant put it on wrong and thats why i like this product. I recommend this along with one of etrailers hitches to make the whole job easier.



by:
2007 GMC Acadia

My Vehicle did not come with a tow package, i need lights to my trailer. My Acadia was wired but dead lights coming out of the connector.
The T-1 took care of all my problems my trailer is tow ready!
The T1 item #118451 is the best solution. I'm very happy with this product.
Thank you e.trailer!!!



by:
2011 GMC Acadia

Hitch was great for my 2011 Acadia. Customer rep’s advice on electrical wiring package, etc. was invaluable. Hitch came in 2 days. I will definitely be ordering from them again.



by:
2010 GMC Acadia

This product went on just like they said it would. It took me about 30 min but that was because I kept looking for a better way too run the wires. One thing that I really like about e-trailer is the videos. This wire harness was for multiple year GMC Acaida's so there were many different videos. I watched each Visio and learned little tricks that helped me install the harness with easy.



by:
2011 GMC Acadia

Hitch was great for my 2011 Acadia. Customer rep’s advice on electrical wiring package, etc. was invaluable. Hitch came in 2 days. I will definitely be ordering from them again.



by:

This harness was easy to install. it took me maybe 30 minutes total time to install. I do wish it came with had a mounting bracket for the plug to mount to the vehicle though. it may be a separate item though.



by:
2010 GMC Acadia

The product I order arrived quickly and was exactly what I ordered. It was high quality and fit my vehicle perfectly. The installation of both the hitch and wiring harness were quite easy with the assistance of the instructions provided.



by:
2012 GMC Acadia

I purchased this T harness for our GMC Acadia. Installation was easy, and the instructions were thorough. It was a little challenging getting the connectors fished through behind the body panels, but all in all it was an easy job. I definitely recommend this over the cheaper kits with crimp on wire splices.



by:

I had a great experience with my purchase. Etrailer.com shipped me my wiring harness very quickly and it was a breeze to install. I just watched their installation video and it told me exactly how to do it. Very pleased !!!



by:
2012 GMC Acadia

I've purchased all of my hitch mounting equipment through etrailer and it's been perfect. The instructional videos that are tailored for a specific vehicle are easy to follow and make installation a breeze.



by:
2011 GMC Acadia

It was easy enough to install. The installation videos are great on etrailer. I've installed two trailer hitches and wiring and all four videos have been excellent. The wiring itself is a pretty simple install.



by:

I bought this product and was able to install it very easily. I am happy with the great quality of the product and the awesome video provided to show you how to complete the installing from start to finish. I also found the installation video for the hitch very useful too. I will not hesitate to come back to etrailer.com for my towing part needs.


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Show More Reviews

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

  • No Running Lights With T-One 4-Pole Harness # 118451 on 2009 Acadia XLT with Tow Package
    The wiring harness you referenced, T-One 4-Pole Harness # 118451 from TowReady, uses plug-and-play connections to your Acadia taillight assemblies to generate lighting signals for your trailer. This harness provides trailer lighting signals on its included 4-pole connector that are completely independent of any factory tow package wiring that may be in place. Please take a look at the linked video which shows installation of this harness in your same year/make/model vehicle. The written...
    view full answer...
    Image 1 for
  • Trailer Running Lights Will Not Work with 2009 GMC Acadia XLT with Tow Package
    First you are going to want to make sure that the running light circuit is working on the trailer connector on the 2009 GMC Acadia. Use a circuit tester such as # PTW2993 to test the running light circuit. If it is not working, then check the vehicle owner's manual for the fuse location for the tow package running lights to check/change it. Also check the owner's manual for any relays that might be needed for the tow package wiring. I do not recommend tapping into the running light wire...
    view full answer...
  • Troubleshooting Trailer Brake and Turn Signals Not Working with Tekonsha T-One Harness on Acadia
    The Tekonsha T-One Vehicle Wiring Harness # 118451 that you referenced plugs in-line with the tail light circuits on your GMC Acadia via factory ports behind the tail lights themselves. The harness and the power it receives from your vehicle should be completely separate from any tow package, as it simply gets power from the factory light circuits. There aren't any fuses related to this harness or its ability to send power back to the trailer lights unless the lights on your Acadia aren't...
    view full answer...
  • Wiring for a 2009 GMC Acadia
    The correct T-One wiring harness for your vehicle is the 118451. Our site lists this harness as being okay for all models – it will work with all LED lights. Please note the tech tip: "Do not splice into the vehicle's wiring system to wire a trailer connector, use only the t-connector that plugs into existing connections." Despite what your dealer indicates, we sell many of the kits, which are then self-installed. I will attach an installation video for your reference below for this product....
    view full answer...
  • How to Install a Trailer Wiring Harness on a 2011 GMC Acadia
    The plug you are referring to in the photo will not be used to install a trailer connector on your 2011 GMC Acadia. The correct way to install a trailer connector on your Acadia would depend on if you have the factory tow package or not. This is an important distinction to make and in order to be sure you know exactly what you have, you will need to obtain your VIN and contact the manufacturer directly. If you do not have the factory tow package then the connections you will need to make...
    view full answer...
    Image 1 for
  • Troubleshooting Wiring on Trailer Towed by 2009 GMC Acadia With Tow Package
    Since you did not find any blown fuses, my suspicion is that the problem lies somewhere in the wiring of the trailer, so let's begin by isolating the problem to confirm that the problem lies in the trailer wiring. Use a circuit tester like part # PTW2993 on the trailer connector as each lighting function is activated. Activate the right turn signal, then test the pins on the connector. Do the same for the left turn, brake and running lamp. If the trailer connector checks out okay, then...
    view full answer...
  • Tail Lights on 2008 GMC Acadia Stop Working when Trailer is Connected
    Let's start with the easy stuff. Make sure the white ground wire on harness # 118451 is attached to a clean bare metal surface on your 2008 GMC Acadia. There can be no coating or paint and it works best if the wire is grounded by itself. If that doesn't help then what is probably going on is the trailer lights draw more power than the vehicle wiring system can handle. You can test this by removing the connections to some of the lights. Then, if everything else starts working, including...
    view full answer...
  • Troubleshooting Running Lights Not Working On Two Trailers Towed by a 2006 Jeep Commander
    This could definitely be a ground problem. Without a proper ground, the circuit cannot be completed which can cause light failure and/or malfunction. You will also want to make sure you are using the correct wiring harness. For a 2006 Jeep Commander with no factory package, you will need to use Tow Ready Custom Fit Vehicle Wiring, # 118408, instructions linked below. With a tow package, you would use Tow Ready Custom Fit Vehicle Wiring, # 118381. I have included a link to the installation...
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  • Trailer Lights do not Work with the Tow Ready T-One Harness # 118451 on a 2010 GMC Acadia
    The Tow Ready T-One Wiring Harness, # 118451, does not require any additional fuses or relays. As you said, this harness provides power to the trailer lights from the vehicles tail light circuits. The only time you would need to install a fuse is if one of the taillight fuses were blown on the vehicle. This would mean your taillights, turn signals or brake lights were not working on your Acadia. If you are positive that you have a good ground and the T connectors are installed correctly...
    view full answer...
  • What is the Correct Trailer Wiring Harness for the 2011 Kia Sorento
    A vehicle specific wiring harness is the best way to get the trailer lighting to work on your 2011 Kia Sorento. If your vehicle has the factory tow package wiring installed you will need the Tow Ready Custom Fit Vehicle Wiring, item # 118451, which will connect to existing connectors located along the frame on the passengers side near the rear tire. The instructions, see link, show pictures of the connectors you will need to use. If your vehicle does not have the factory tow package wiring...
    view full answer...
  • Troubleshooting Tekonsha T-One Trailer Harness Not Working on 2012 GMC Acadia
    The Tekonsha T-One Wiring Harness # 118451 that you ended up installing is the correct harness for your 2012 GMC Acadia and it will work whether or not you have the tow package so you made the right choice there. If you happen to have your trailer on hand, the first thing I recommend doing is simply hooking it up to the Acadia and plugging in your connectors. Sometimes those LED testers can be a little finicky so it's possible that the harness works perfectly and the tail lights on the...
    view full answer...
  • Adding a 5-Way Flat Trailer Connector to a 2012 GMC Acadia
    In order to install a 5-Way flat trailer connector on your 2012 GMC Acadia you will need 2 items. First, since your model does not have the factory tow package, you will start by installing a 4-Way # 118451. With the 4-Way installed you will just need the second item which is a 4- to 5-Way adapter, # 20036. The adapter has an extra wire that will need to be spliced into a reverse light wire. You may be able to find a reverse light wire behind one of the tail lights by probing the wires...
    view full answer...
  • Troubleshooting Passenger Side Trailer Lights Not Working Until Trailer Is Hitched To Truck
    Based on your description it sounds like if the trailer is not hitched to the truck but the wiring harness is plugged in the passenger side trailer tail lights do not work, but if the trailer is hitch to the truck that the lights starting working. If this is the case then there is a ground issue on either the truck or trailer. I recommend starting with the main trailer ground on the tongue of the trailer making sure it is securely connected to clean corrosion free metal. If those grounds...
    view full answer...
  • Troubleshooting No Trailer Turn/Brake Signals with 2007 GMC Acadia
    I do agree that the wiring issue you are experiencing is somewhere on your Acadia. You mentioned that the Acadia didn't come with the tow package but it does have the trailer wiring and hitch. This means you likely have a T-Connector wiring harness installed such as the Tekonsha # 118451 that plugs into factory ports behind the tail lights. What I recommend doing is checking the white ground wire coming from the harness. Make sure this is still securely attached to a clean, bare metal...
    view full answer...
  • Recommended Wiring For A Trailer With Brakes For A 2011 GMC Acadia
    For your 2011 GMC Acadia, I recommend you start with the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118451. This will give you a 4-way flat as you mentioned. Then you will need the Universal Installation Kit for Trailer Brake Controller # ETBC7. This kit will give you the wire, connectors, and circuit breakers you need to connect a brake controller to a 7-way for a trailer with brakes. For your brake controller, I recommend the Tekonsha Prodigy P3 Trailer Brake...
    view full answer...
  • Will Adding a Trailer Hitch to a 2010 GMC Acadia Damage the Frame
    That's ludicrous, you can absolutely install a trailer hitch on a 2010 GMC Acadia without damaging the frame. The etrailer Trailer Hitch Receiver part # e98863 is what I recommend, it offers a bolt-on fit without any drilling or welding. It's covered under a lifetime warranty as well. It installs in the same manor as the factory hitch that would have come on the vehicle if equipped with the factory tow package from the factory. There isn't any sort of extra bracing on models with the factory...
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  • Does T-One Harness Part # 118451 for 2008 GMC Acadia need Other Parts due to LED Tail Lights
    I spoke with one of our installers who has installed T-One harness part # 118451 on a 2008 GMC Acadia, and he said you should have no problems. If a T-One harness needs a converter, it will have one built in, but in this case it does not. We also have a video of this part being installed on a 2008 GMC Acadia and I will add a link to it below.
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  • How To Install The Draw-Tite Class III Hitch # 75528 On A 2009 GMC Acadia Without Existing Weldnuts
    When installing the Draw-Tite Class III 2 Inch, part # 75528, on a 2009 GMC Acadia, some of the vehicles will not have the weld nuts on the front two mounting holes of the bumper. What you will need to do if you are missing the weld nuts is to use the included handle nuts that will come with the hitch. The handle nuts are used in many trailer hitch installations because of the limited space that is available for installing mounting bolts. The handle nuts are a nut with a handle attached...
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  • Troubleshooting No Power On T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118451
    I would start checking fuses and relays on the power block in the engine bay. The cover should have a map or listing of all the fuses. Check all of the fuses that have anything to do with taillights or tow circuits. I have added a link to a wiring FAQ page that shows which pins should serve which function. Use the circuit tester like # PTW2993 to make sure everything is on the correct pins.
    view full answer...
  • Installing Brake Controller and 7-Way Wiring on 2012 GMC Acadia without Tow Package
    It can seem really random what vehicle manufacturers decide to include and exclude on vehicles without tow packages in terms of circuits they do install and those that aren't there. So you for your 2012 Acadia you have the brake controller power, ground, and stoplight circuit but basically everything else is non-existent. So what you are going to need to do is install the 4-way kit part # 118451 to give you the taillight circuits you'd then need to wire to your 7-way directly after cutting...
    view full answer...
  • Trailer Wiring Recommendation for a 2014 GMC Acadia
    For a trailer wiring kit confirmed to fit your 2014 GMC Acadia you would want the Tow Ready harness part # 118270. It will not require you to run a power wire up to the battery as it comes with fuses and relays to complete the circuits.
    view full answer...
  • Troubleshooting Left Stop/Turn Signals on Trailer Towed by 2007 GMC Acadia
    You have already started the troubleshooting process to find the cause for your trailer's left-side turn and brake lights not working. Since another vehicle has no issue with this trailer this does tend to suggest that the issue is on the Acadia. Since both 4-pole and 7-way trailer wiring setups combined the left stop and turn signals onto one wire, typically a yellow one, what I suggest is that you start a close inspection of this circuit/wire at the trailer connector itself. You can...
    view full answer...
  • 4-Way and 7-Way Trailer Connector for 2010 GMC Acadia
    I have a solution for you, and you will not need to cut into any wires. If you do not have a factory tow package on your 2010 GMC Acadia, you will first need to install a 4-way wiring harness. I recommend the Tow Ready T-One Vehicle Wiring Harness # 118451. This wiring harness will plug directly into the back of your taillights, into your vehicle's current wiring system. I have attached an installation video of this harness on a 2011 GMC Acadia. The wiring harness has a 4-way flat connector,...
    view full answer...
  • Trailer Lights Malfunction on a Small Utility Trailer Behind a 2009 GMC Acadia with Factory 7-Way
    Vehicles with LEDs will have problems with standard trailers unless a powered tail light harness is used, or there is a factory tow package. If your 7-Way on your Acadia is indeed a factory connector, you should have no problems with LEDs vs. incandescent lights. Most small utility trailers do not have a 7-Way. 7-Ways are used on larger trailers that have electric brakes, or hydraulic systems powered by a battery, or boat trailers with hydraulic actuators with reverse lockouts. If your...
    view full answer...


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