T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
(112 reviews)
Price: $52.39
In Stock
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
Item # 118790
Retail:$62.57
Our Price: $52.39
You Save: 16%
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- All Info
- Reviews (112)
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Tekonsha Custom Fit Vehicle Wiring - 118790
- 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.
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
- Locate connection point 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
- Comes with dust cap for 4-way flat connector
Specs:
- Maximum amperage:
- Stop/turn lights: 5 amps per circuit
- Tail lights: 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 inside your trunk, behind the rear interior trim panel on the driver's side of the rear cargo area. You will need to remove access panels, threshold, trunk floor panels, and trays to access the harness. Once you've plugged in the T-connector, pull back the interior trim panel on the driver's side and locate the ground stud. Loosen the bolt, place the screw eyelet on the stud and re-tighten the bolt.
Once installation is complete, the 4-way flat connector will be stowed in your 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.
118790 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite
Installation Details
This Product Fits The Following Vehicles
- 2019 - 2024 Subaru Ascent
- 2019 - 2024 Subaru Ascent
California residents: click here
Customer Satisfaction Score:
97% were satisfied with this product
3% of customers were not satisfied
- Wrong item was ordered
- etrailer mistake
- Defective
Customer Reviews
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118790
Average Customer Rating: 4.9 out of 5 stars (112 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.by: Greg01/05/2024
The product had all the necessary instructions and parts to make the installation very easy. The harness is very simple to use.
by: Jennifer09/22/2022
All parts arrived in a speedy manner and in great condition! Big thank you to Brent J for all his hard work and extremely fantastic customer service!! Easy to follow install videos for tow hitch and electrical components. Thanks etrailer Team!!
by: Linda09/29/2023
Solid product. Very clear and accurate installation instructions customized exactly to my specific vehicle year and model.
by: Sean 01/10/2023
2019 Subaru Ascent
Fit perfect and the DIY video was spot on
by: John03/24/2021
Easy install. Bought this with the Curt Class III hitch. All components match up and install without a struggle. The Tekonskha Custom Fit harness incorporates turn signals, running lights and brake lights.
by: Steven04/20/2022
2022 Subaru Ascent
Very easy installation, I followed the video online and got it down very quickly.
Great instructions and installation!
Steven
4/21/2023
It’s been a year already?!, time flies and it works great! Doing some remodeling and had to hook up my old harbor freight trailer to haul the deconstructed 10x20 shed to the dump. Wiring was fine!
by: Beau02/22/2022
Subaru
This worked well on my 2020 Subaru Ascent. The only reason for 4 stars instead of 5 is due to there not being a clamp or something to hold the final cable in place. It isn’t a big deal, you can tuck it into the bumper and that seems to be fine but would have liked a better setup there. Overall great harness and pretty easy to install.
Beau
2/23/2023
Been great over the past year. Used it on a few different trailers and uhauls. No issue and the harness hasn’t fallen out so no issue there
by: TW05/16/2023
Best experience I have ever had buying car parts! Sales person (Melissa) was competent Delivery was 2 days (a day ahead of schedule), instructional videos were concise and clear. Trailer hitch and harness were well made and fit perfectly. Installed cost was less that a fourth of OEM quote.
by: Aaron 04/18/2023
2020 Subaru Ascent
This harness was super easy to install and run down through the grommet to the hitch for easy access. I ended up adding some plastic wire loom for protection under the car but was highly satisfied with all of the components in the kit. Watch the video clip for some tips and order with confidence!
by: Joseph 03/15/2023
2021 Subaru Ascent
Received my order in a timely manner. Very pleased with the hitch and wiring. Installation went smooth due in part to excellent videos.
by: Randall06/11/2023
2019 Subaru Ascent
Super simple to install, and the video was very specific to my vehicle.
by: Jeff 06/01/2023
Etrailer had what I needed a good price and came a day earlier
by: John 04/30/2020
Subaru
I purchased this for my 2019 Subaru Ascent along with a Drawtite hitch 76253 and a brake controller with a dash mounted control knob so that the actual controller is hidden near the steering wheel shaft hidden under the dash. All three items were installed and we enjoyed a great summer of RV trailer camping in the summer of 2019.
John
5/1/2021
I had an RV service professional install it because I am too claustrophobic under my Ascent and I am very happy that it is hidden behind with only the control button visible and it works great!
by: Benjamin06/15/2022
Works perfectly. Easy install.
Benjamin
6/16/2023
No problems, no regrets!
by: Russ11/25/2022
I’m very pleased with the wiring harness and tow bar. Both were very easy to install. It only took about 3 hours and no cutting or drilling was needed. I’d buy again
by: Allyson05/05/2022
Super easy to install.
Allyson
5/6/2023
Continues to work great. Really happy with this purchase.
by: Daniel05/28/2022
Great product. Works perfect and was very easy to install and disappears when not in use.
by: Charles 01/07/2023
2021 Subaru Ascent
Very simple to install. Instead of letting the wire hang out out of trunk when using like the install video showed I tucked it under the trim and behind the bumper before I put the bumper back on after installing the hitch
by: Peg07/11/2023
Just what I needed!!
by: Travis P.03/29/2019
Arrived quickly with my hitch and, after watching the video (A must!), it installed very easily and quickly with no surprises! This can easily be installed with just the tool needed for attaching the ground wire.
Travis P.
3/30/2020
Great! Required some voltmeter testing to match the right wire to the right harness wire though.
by: Steven 09/14/2022
2022 Subaru Ascent
The product works without issue and was easy to install. The reason for 4 stars versus 5 stars is simply the fact it just hangs out your tailgate. There was no mounting options to run it out of sight.
by: Alexander07/01/2023
No complaints, easy to install.
by: Bruce 08/23/2020
Very easy to install. The only difficulty is actually getting to the place where the harness is to be placed. Instructions are easy to follow and, with a little care, the system can be installed with no issues.
Bruce
8/24/2021
Still working very well.
by: Dennis04/28/2020
I ordered this item along with the trailer hitch and a bracket. The item was packaged great and arrived in timely fashion. The company was fantastic to work with and service was outstanding.
Finally, the online tutorials on the etrailer website made putting these items in place easy.
I am 150% satisfied with everything this company has done!
by: Brian 07/17/2021
2020 Subaru Ascent
I have been using etrailer.com for several years on multiple vehicle hitch and wiring projects and I have always been very pleased with the product and my experience. This time was no different. I needed to install a hitch and wiring harness for a 2020 Subaru Ascent. The parts that were matched with my vehicle online fit perfectly. The instructional videos that accompany every part are outstanding. Each step is clearly explained and easy to follow. Once again, etrailer.com delivered exceptional service, prices, parts, delivery, and everything else I needed to complete my hitch and wiring project in just a few hours. I highly recommend etrailer.com and I will continue to be a customer for several decades to come.
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Do you have a question about this Custom Fit Vehicle Wiring?
Info for this part was:
Edited by:
Lindsey S
Installed by:
Jeff D
Video by:
Joshua S
Video by:
Dustin K
Video Edited:
Jacob T
Video Edited:
Chris R
Updated by:
Wilson B
Updated by:
Hannah L
Updated by:
Isabelle B
Written by:
Alexander C
Test Fit:
David F
Test Fit:
Ryan G
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Sean
1/10/2024
Still working without issue