bing tracking image
  1. Custom Fit Vehicle Wiring
  2. Tekonsha
  3. Custom Fit
  4. Trailer Hitch Wiring
  5. 7 Round - Blade
  6. No Converter
T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector

T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector

Item # 118271
Our Price: $62.92
You Save: 19%
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.

Shipping Weight: 1.24 lbs
Add to cart
118271 - Custom Fit 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

Customer Photos

Need help with installation?
Locate installers near me
Quickly and easily install a 7-way, RV-style trailer connector on your vehicle with this custom wiring harness. T-One connector plugs into OEM tow package wiring harness - no cutting, splicing or tapping required. 1-800-940-8924 to order Tekonsha custom fit vehicle wiring part number 118271 or order online at Free expert support on all Tekonsha products. Great prices and Fastest Shipping for T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
  • All Info
  • Reviews (174)
  • Q & A (0)
  • Photos

Tekonsha Custom Fit Vehicle Wiring - 118271

  • Custom Fit
  • Trailer Hitch Wiring
  • 7 Round - Blade
  • No Converter
  • Tekonsha

Quickly and easily install a 7-way, RV-style trailer connector on your vehicle with this custom wiring harness. T-One connector plugs into OEM tow package wiring harness - no cutting, splicing or tapping required.


  • Provides a 7-way, blade-style 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 4-pole, 5-pole, and 6-pole adapters (sold separately)
  • Connects quickly and easily - no cutting or splicing of wires
    • Insert fuses and relays (included) in engine compartment
    • Locate connection points along frame rail
    • Plug in connectors
  • Constructed of 16-gauge bonded wire
  • Mounting bracket sold separately
  • 1-Year limited warranty


This custom-fit T-One connector plugs into your vehicle's factory tow package wiring harness, which is located beneath the vehicle, near the frame rail on the passenger's side. Once you've plugged in the connectors, insert the included fuses and relays into their locations in the fusebox, which is located in the engine compartment.

Once installation is complete, the 7-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 7-pole connector itself - to help prevent corrosion.

118271 Tow Ready T-1 T-Connector - OE Replacement - 7-Way

Installation Details 118271 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 - 7-Way Trailer Connector - 118271

Average Customer Rating:  4.8 out of 5 stars   (174 Customer Reviews)

Quickly and easily install a 7-way, RV-style trailer connector on your vehicle with this custom wiring harness. T-One connector plugs into OEM tow package wiring harness - no cutting, splicing or tapping required.


Easy to plug in as advertised. Hardest part was having to remove the back bumper to route the wiring away from hot components. The eTrailer installation video was very helpful for the rest.



Still works great after a year. No issues.


Product fit perfectly to the factory connector( it was a bit difficult to access it tho.) installed rather quickly with the exception of the bracket for the plug. Awesome part!

2017 GMC Acadia

Made adding the hitch and wiring a snap to my 2017 Acadia Limited

2013 Chevrolet Traverse

Went on fairly simple. I wish it would’ve been able to mount to the hitch. This one didn’t but it works


Wiring harness was easy to install. The existing plug on the car is held up in the wheel well with a clip. Unhooking it helps to access and snap the two plugs together. I was able to re-hook the end which helps keep the harness supported at that point. Note - you should use a dialectic gel on both plug and receptacle ends. This helps to waterproof and avoid corrosion at the connection. Follow directions to avoid contact with the tail pipe and strap accordingly.
Adding in the fuses in the fuse block was easy, The only issue I had was installing the two relays. Most relays require installs in a certain direction to be certain the coil and contacts are not reversed. I did not see any indicator to tell me which direction they must be installed. The red circled relays in the photo are the ones I'm talking about. It took me about a half hour to complete the project. That time also included installing the 4/7 pin adapter receptacle that this harness plugs in to at the hitch.


I bought the trailer hitch and one of the connectors that were recommended and the connector bracket does not fit so I need a different connector. Also the angle on this hitch doesnt seem right. I bolt the 4 m12 bolts in and then the theres a gap of 1/2 inch where the 1/4 inch spacers are supposed to go.

2015 Chevrolet Traverse

Like many others stated, super easy installation of the hitch. Only took me about 30 min by myself. It took me about an hour for the wiring harness and bracket since I had to find another bolt and nut since it only came with 3. The thing that gave me the most trouble was the wiring harness. I couldn't bring the cannon plug down towards me at all so I had to do it all by feel. The mounting bracket for the wiring harness I chose to flip upside down and bend towards the rear of the car and down so I could hide the wiring and hitch completely. The other reason was because I didn't want the bracket to catch on anything because it was lower than the bumper. I ordered the supplies on Fri and they were here mid day the following Tuesday. With all the great videos, a job that might have taken me 4-5 hours only took 2 hours plus knowing where the cannon plug was helped tremendously. If I hadn't known where it was I would have prob had to do a splice job. This job, in my opinion, looks professional. Thanks ETRAILER.


Product fit exactly as described. I want to be able to tow a small camping trailer. I have family visiting from Washington State. I needed a 2nd tow vehicle ETRAILER had all the parts I needed to prepare my buick for towing.


direct fit and clear directions, I zip tied it to the hitch frame.

2016 Chevrolet Traverse

Perfect fit and length. Only issue was it does not come with a bracket to mount the plug to the hitch. I guess it has to dangle or I wire tie it up, until I get one now.

2015 GMC Acadia

This kit was very easy to install. Plug and play.


Easy installation.


Package delivered a day early!!
parts as always!


Excellent product and service from a trustworthy company. I have purchased from etrailer in the past and was not disappointed in quality and workmanship. This recent purchase was also very satisfying in the fact that with etrailers excellent customer service reps the purchase I made was the exact part I needed. When I ran into a slight problem on Saturday, just one phone call resolved the issue. I take great pride in being able to complete a project by myself other than relying on a dealership who would charge me double for the same thing. I would highly recommend etrailer to anyone looking for trailer parts and hitches. Fast curtious service and knowledgeable reps make etrailer number one place to purchase.

Gary Y.


Great works as described.


Arrived fast and installed easily, plug and play!


Fit and works perfect

2016 Chevrolet Traverse

I installed the trailer hitch and wiring harness yesterday without any problems. The great videos helped a lot. Products and service are outstanding.

Mike C.




the hardest part was getting a good grip on the truck side of the plug, not a lot of room.

2014 GMC Acadia

The trailer hitch has been fine but I have had intermittent problems with the trailer wiring for a year now ( I only use the trailer a few times each year). The left blinker on the trailer intermittently quits working. When this happens, the tail lights on the left side are brighter than the right so I believe the blinker lights are shorted to the tail lights but not connected to the vehicle blinker signal. I am able to wiggle the wires near where the cable connects to the vehicle connecter and the blinker begins working and the tail lights are the proper brightness. I can't disconnect the cable from the vehicle wiring without putting the car on a lift so I have not been able to determine whether it's a problem with the vehicle wiring or the trailer light cable without taking the vehicle to a shop which I have avoided so far. The trailer wiring is fine and works with other vehicles so I know its not the trailer. The cable is properly routed around any hot exhaust pipes so it appears to be installed correctly. I plan to take it in soon as I am tired of fiddling with it to get it to work.

2015 Chevrolet Traverse

Be careful what you order. I ordered the 4 pin but really should have ordered this 7 pin. My bad, I get it. etrailer determines the return shipping cost. The 7 pin installed no problem.



Great but it would be nice to have included stainless steel hardware

2015 Buick Enclave

Easy installation on my 2015 Buick Enclave as long as you have small enough arms to reach up under the side. One downside was there wasn't a mounting bracket included, so the wiring is hanging while I search to get one. Also, the zip ties included were not long enough to attach anywhere affectively, so I had to use some I purchased another time.

Etrailer Expert

Mike L.


We can help you with a mounting option for your trailer connector! If your trailer hitch already has a bracket on it, you can simply use part # PK12711U. If the hitch doesnt have a bracket, youll need the PK12711U and a no-drill bracket, 18136. Drilling directly into the hitch is not recommended as it can weaken the hitch.

2016 Toyota RAV4

I received excellent customer service from etrailer! They were able to guarantee arrival of the part days ahead of my local parts supply store. (The local parts supply store also tried to sell me a part that would not fit my vehicle.) The customer service representative at etrailer was very helpful, courteous, knowledgeable, and well spoken.

The Part itself, a wiring harness to add a trailer plug on our vehicle, appears to be high quality, and fit my application perfectly. I was able to simply plug the wiring harness into the existing factory plug at the rear of our vehicle.

Two things would have made the wiring harness, a Tekonsha product, better. The wiring harness did not come with any di-electric grease, which should be provided for any exterior electrical connection. I had to supply my own di-electric grease for the project. And while the part did come with four supplied zip-ties, they were too short to properly attach the wiring harness to much of anything underneath our vehicle. I had to supply my own, longer and stronger zip ties for the project.

All in all, a great product, and backed by excellent customer service from


Beyond pleased with this company. The videos they made helped so much. I would reorder if I had to do it all over again. Thank you.

2015 Buick Enclave

I installed the 7 Pin wiring harness and connector. Everything was straight forward and simple. I installed all the fuses and relays provided as instructions. Everything worked except the Backup portion. The kit included relays for Left turn/Stop and Right turn/Stop but no relay for the trailer Back/up. In the instructions, the picture provided, it does show a relay in the Trailer Back/Up socket.
I took one of the turn/Stop relays and put it into the Trailer Bk/Up position and I had power on the Backup Pin on the connector. The kit came with 2 relays but it should come with 3 relays.

2015 Saturn Relay

I sure would like to rate this wiring harness 5 stars but I had one concern about the order the colors were after installing which the hardest part was to reach the plug behind the rear tire I checked out the positions of the pins they checked out also receiving the fuses and the relays to finish the job was great I do wish the trailer brake backup light relay came with it but not many trailers have backup lights wiring was also delivered in a timely manner when I did have concern about the order they were very helpful with e-mails back and forth to me thank you

Show More Reviews

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

  • Where Is The Trailer Tow Wiring Located On 2017 Buick Enclave
    The trailer wiring on the 2017 Buick Enclave is on the rear passenger side of the Buick just to the right of the muffler. Look for an opening to the right of the muffler for wiring with a grey plug on the end. You may need to reach into the opening to find it. The protective covering needs to be removed and discarded. I have attached a photo of what the plug is going to look like. If you still cannot find it please let me know and we can troubleshoot further.
    view full answer...
  • What Gauge Wire is Used on the T-One Vehicle Wiring Harness # 118271
    The Tekonsha T-One Vehicle Wiring Harness, # 118271, uses 10 gauge wire. This vehicle wiring harness will work well on your 2016 Chevrolet Traverse and help maintain the 12volt charge on your trailer's battery. I have attached a couple videos on this wiring harness for your to review.
    view full answer...
  • Installing Tow Ready # 118270 Trailer Wiring Harness on 2015 Chevy Traverse
    According to my contact at Tow Ready, as along as all the fuses and relays included with the # 118270 are correctly installed, the trailer connector should work just fine. The # 118270 will work regardless of if the vehicle was equipped with the tow package or not, as long as the connector for the harness is in place under the vehicle. If you click the provided link, you can see the installation instruction for the # 118270 wiring harness. I've also linked you to a video showing the trailer...
    view full answer...
    Image 1 for
  • Location of a Fuse/Relay Diagram to Install Trailer Wiring on a 2014 Chevy Traverse
    The fuse and relay legend or diagram should be stamped or printed on a sticker on the underside or the top of the fuse box cover. If you can't find it there it will also be listed in the owners manual. If you lost your owners manual you can do an internet search for "2014 Chevy Traverse Owners Manual," and you should be able to download a .pdf file of the manual.
    view full answer...
  • Not All Pins On T-One Vehicle Wiring Harness Part # 118271 Have Power
    If the T-One Vehicle Wiring Harness part # 118271 is not working correctly then odds are you have an issue in the vehicle's fuse box. The trailer lights are on a separate circuit that the vehicle's tail lights so there will be separate fuses for the trailer lighting circuits. If all fuses check out then test the square pigtail on the vehicle before the signals are carried into the wiring harness. If you get power on all circuits at the square pigtail then you know the trailer wiring harness...
    view full answer...
  • 7-Way Trailer Wiring Recommendation for a 2016 Chevy Traverse
    To install a 4-way on your 2016 Chevy Traverse would require you to install the part # 118270. To install a 7-way (if you didn't have one) you would only need the part # 118271.
    view full answer...
  • How to Find the Wiring Harness on a 2017 Buick Enclave
    I sure the wiring harness is there and I get your frustration because even our installers have mentioned how difficult it is to find it. I have linked a video below for the item # 118270 4-way wiring harness. It uses the same connector as the item # 118271 you are looking to install in your Enclave. If you skip forward to the 1:35 point of the video you'll see the step. If your 2017 Buick Enclave does not have the towing package you will still have the rectangle connector needed to attach...
    view full answer...
  • Recommended Trailer Wiring for 2017 Buick Enclave
    For your 2017 Buick Enclave, I recommend the T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector # 118271 which will connect to factory wiring and includes the fuses and relays to activate the tow package even if your vehicle did not come with one. This wiring harness will be tucked up under your side panel underneath on the passenger side which is difficult to see in the attached a video of the similar Chevy Traverse. If you just want a 4-way wiring harness,...
    view full answer...
  • Troubleshooting Trailer Lights Not Working with T-One 7-Way Connector Install on GMC Acadia
    That is really interesting that you are having the same problem with the left running and turn signals on your trailer since you are seeing power on that pin for the T-One # 118271. If you check out the linked installation instructions you can see that the stop/turn and tail (running) light circuits have a max rating of 10 amps. What you might want to try doing is testing both your trailers independently of your GMC Acadia. It would make sense that the turn signal wouldn't work on one...
    view full answer...
    Image 1 for
  • Installing a 7-Way Trailer Connector on a 2011 Chevrolet Traverse with Tow Package
    The wiring harness # 118271 is for 2013 and later Chevrolet Traverses so it is not the correct part for your 2011. The harness may plug in the same but it also includes the fuses and relays which aren't confirmed as a fit. Since it sounds like your 2011 Traverse came with the tow package you can use the # 74682. According to the owner's manual for your Traverse that I found online you will not need to install any fuses however the wires for the trailer brake circuit will need to be connected.
    view full answer...
  • Will I Have A Plug For Wiring Harness In Frame Rail Of 2015 GMC Acadia Without Factory Tow Package
    It looks like the difference between a tow package and not having a tow package on the 2015 GMC Acadia is needing to add relays. Whether the Acadia has a tow package or not there will be a port to plug a wiring harness into. If you need a 4-pole flat you can use part # 118270 to plug into OEM port. It also comes with the relays to activate the towing package. If you want a 7-way connector you need 7-Way Trailer Connector Wiring Harness part # 118271 that plugs into the same plug near...
    view full answer...
    Image 1 for
  • Trailer Wiring Harness for a 2009 to 2012 Chevy Traverse
    The Tow Ready trailer wiring harness # 118450 is designed to fit all models of the 2009 to 2012 Chevy Traverse. I have included a link to a video showing installation on a 2012 Traverse for you.
    view full answer...
  • Trailer Wiring Recommendation for 2013 Chevy Traverse with Rear AC Controls
    For trailer wiring for your 2013 Chevy Traverse that has the rear AC controls you would want the part # 118270 which we have confirmed as a fit for your vehicle configuration. I attached an install video for this kit for you to check out as well.
    view full answer...
  • Troubleshooting Trailer Wiring with No Stop Lights or Turn Signals
    Sounds like a weak ground on the trailer wiring since both the turn signals are no longer working. Make sure the main ground wire from the connector on the trailer is ran to a clean portion of the trailer frame and also make sure the grounds of the assemblies are making good contact as well. They may ground through the mounting hardware so make sure they are connected to a clean metal surface. You can also run a jumper ground wire from the assemblies to the main ground circuit as well....
    view full answer...
  • Trailer Wiring Harness Recommendations for a 2016 Chevy Traverse 2LT AWD
    I will be happy to help you select a trailer wiring harness so you can get out there and get to camping! There are a couple of different ways you can add a trailer wiring harness to your 2016 Chevy Traverse: install a harness that plugs in line with the tail light wiring or use a harness that plugs into a factory location and that also provides the accessories to make it functional. The second way is the easier installation so I recommend we look at the best option in that category. If...
    view full answer...
  • Is There A Reason The Curt T-Connector Harness Comes With More Relays Than The T-One Harness
    I have taken a look at both instruction manuals, the T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector, part # 118271, and the Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector, part # C56245. Each of these wiring harnesses use only two relays during their installation. The Curt wiring harness includes an extra relay and both harnesses include an extra 30A fuse. I have included installation videos of both wiring...
    view full answer...
  • 7-Way Trailer Wiring Harness Recommendation for 2016 GMC Acadia
    The correct 7-way trailer wiring harness you need for your 2016 GMC Acadia is the Tekonsha part # 118271 which comes with all of the needed relays and fuses to activate the towing package as well.
    view full answer...
  • Why Cant a T-Connector Trailer Wiring Harness be Installed On 2013 Chevy Traverse with Rear AC
    I checked with our installers and the rear AC unit blocks the access to the right side tail light wiring. In order to install harness # C56181 on your 2013 Chevy Traverse the harness would have to be modified, basically making it more of a hardwire installation which will void the harness warranty. Instead of having to deal with that I recommend using a hardwire harness to start with, # 118271.
    view full answer...
  • 2017 Chevy Traverse Troubleshooting No Power for T-One Trailer Wiring
    The T-One Vehicle Wiring Harness # 118271 does come with all of the fuses and relays for your 2017 Chevy Traverse, but if all of those look good I'm wondering if the issue is on your vehicle side. It's definitely possible that it could be the T-One wiring but I recommend using a circuit tester like part # PTW2991 to see if the locations for the fuses are actually passing the power for the circuit. If nothing is happening at the fuse/relay positions then you'll need to take your Traverse...
    view full answer...
  • Would the Tow Ready 7-Way # 118271 fit a 2010 GMC Acadia
    What you can do is test the pins of the connector you found with a circuit tester like the part # PTW2993 and if they activate the tester with the different taillight circuits being applied the connector is active and the # 118271 would work.
    view full answer...
    Image 1 for
  • Has T-One Vehicle Wiring Harness # 118271 Been Confirmed to Fit 2014 Chevrolet Traverse
    The T-One Vehicle Wiring Harness, # 118271, does indeed fit the 2014 Chevrolet Traverse as well as the 2013 model. Glad to hear that you located the hardware kit for your Draw-Tite Trailer Hitch Receiver, # 75528. I have attached an installation video for you to check out.
    view full answer...
  • Recommended Brake Controller for 2017 Buick Enclave Without Tow Package
    You will still need a brake controller after installing the T-One Vehicle Wiring Harness for Factory Tow Package - 7-Way Trailer Connector # 118271 on your 2017 Buick Enclave. Since your Enclave didn't come with the factory tow package you won't have a plug and play adapter for a brake controller, so I recommend going with a wireless unit. The wireless controller I recommend using is the Curt Echo Wireless Trailer Brake Controller - 1 to 2 Axles - Proportional # C51180 since it lets you...
    view full answer...
  • Will the 7 and 4-Pole Trailer Connector Socket Part # HM40975 Fit a 2015 GMC Acadia
    The 7 and 4-Pole Trailer Connector Socket part # HM40975 is designed to replace the 7-way on a 2015 GMC Acadia with the factory tow package. Since you do not have the factory tow package you would need the wires that connect to the bumper in addition to the fuses/relays to active the factory tow package. For this, I recommend using the T-One Vehicle Wiring Harness part # 118271. Once this harness is installed you can then replace the included connector for the one listed above to give you...
    view full answer...
  • Can a 4- and 7-Way Connector be Used on Wiring Harness 118271 for a 2014 GMC Acadia
    The relays, fuses, and wiring harness for # 118271 are not available separately. But if you did get # 118271 and replaced the 7-Way with Hopkins 4- and 7-Way # HM40975 you would at least have a spare 7-Way should something happen.
    view full answer...

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

Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Kathleen M
Video by:
Kathleen M
Employee Zach D
Video by:
Zach D
Employee Laura H
Written by:
Laura H
Employee Cole B
Installed by:
Cole B
Employee Randy B
Test Fit:
Randy B
Employee Shane H
Test Fit:
Shane H
Employee Robert C
Test Fit:
Robert C
Employee Wilson B
Updated by:
Wilson B
Employee Alexander C
Updated by:
Alexander C
Employee Isabelle B
Updated by:
Isabelle B

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.

Product Experts Available Now!
Call 1-800-940-8924