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  1. Custom Fit Vehicle Wiring
  2. Tekonsha
  3. Custom Fit
  4. Trailer Hitch Wiring
  5. 4 Flat
  6. Converter
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

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

Item # TK77FR
Retail:$146.00
Our Price: $100.68
You Save: $45.32
Custom Fit Vehicle Wiring

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TK77FR - Custom Fit Tekonsha Trailer Hitch 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 existing wiring. Powered ModuLite reduces strain on wiring system. 1-636-306-4830 to order Tekonsha custom fit vehicle wiring part number TK77FR 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.
  • All Info
  • Reviews (19)
  • Q & A (0)
  • Photos
  • Why etrailer?

Tekonsha Custom Fit Vehicle Wiring - TK77FR

  • Custom Fit
  • Trailer Hitch Wiring
  • 4 Flat
  • 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 points in rear cargo area
    • Plug in T-connector
    • Run hot lead to car battery
  • Includes ModuLite power module that 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 in the rear cargo area. You will have to remove the plastic threshold cover, side panels, cargo trays, and interior trim panels to access this harness.


Once you've plugged in the T-connector, run the hot lead up to your car battery. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery and insert the provided fuse.


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 Power Module

A ModuLite power module is built into this T-One connector. 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.



118823 Tekonsha T-1 T-Connector - 4 Wire - Modu-Lite Converter Included

Installation Details TK77FR 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 - TK77FR

Average Customer Rating:  4.9 out of 5 stars   (18 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.

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plug and play with no issues, everything you need in this kit.




by:

Worked perfectly plug and play no complaints at all.




by:
2018 BMW X3

Great video on how to install, complete kit with everything you need.




by:

We are happy with our whole package including hitch, receiver, wiring and ball mounts.




by:
2018 BMW X3

The video is direct and helpful.




by:

Looks good, hopefully it is plug & Play




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Great price and very fast shipping




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2019 BMW X3




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Very easy




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19
19

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

  • Recommended 4 Flat Trailer Wiring Harness for a 2021 BMW X3 M40i
    You are correct in that your 2021 BMW X3 M40i isn't actually from the actual M division, so it does make the correct wiring look difficult to locate. However, the 2021 model year makes life significantly easier as the Tekonsha T-One # TK77FR will fit both the M and non-M models, so this is definitely the harness I recommend for you. Other than a wire that will need to be run up to the battery for needed power, it will be a plug and play option. It is always a good idea to reset the vehicle's...
    view full answer...
  • Recommended Plug And Play Trailer Wiring Harness For A 2020 BMW X3 M
    The Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat # TK77FR will definitely fit your 2020 BMW X3 with the M package. Though you do need to run a wire up to the battery for needed power, this will be a plug and play harness, so it is a lot easier to get installed than some other ones. With that said, not having done an install with this on a 2020 as of yet, I can't really say if there will be any difference between the video we have on the 2019 and your 2020. With it being plug...
    view full answer...
  • Custom Wiring Harness for a 2022 BMW X3
    Yes, the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector item # TK77FR has been confirmed to fit all models of the 2022 BMW X3 except for the BMX X3 M's.
    view full answer...
  • Does My BMW 2022 x30i Need to Be Recoded After Installing the Wiring Harness
    No, the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector item # TK77FR does not require you to have your car recoded. It is a good idea to disconnect your battery and then reattach the battery to your system after the install is completed. This will not affect your bumper sensors.
    view full answer...
  • Does The T-One Wiring Harness Activate Trailer Mode On A 2018 BMW X3
    When installing The T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # TK77FR on your 2018 BMW X3 once the harness is installed and plugged into the trailer, trailer mode is activated. The trailer wiring harness has a simple plug and play installation that plugs behind the driver and passenger side tail lights externally. The wire is constructed of 16-gauge bonded wire. I attached an installation video link below.
    view full answer...
  • Trailer Hitch and Wiring Recommendation 2022 BMW X3
    For your 2022 BMW X3 M40i the Draw Tite hitch part # 76226 is a great option. This hitch has great towing capacities and is mostly hidden since only the hitch opening hangs below the rear bumper which allows better ground clearance as well. If you needed trailer wiring the Tekonsha kit part # TK77FR would be a really great option as it installs easily and has a very reliable converter box.
    view full answer...
  • Curt Trailer Hitch Receiver Install on 2019 BMW X3
    The Curt Trailer Hitch Receiver # C13387 comes with everything needed to install on your 2019 BMW X3. If you are planning on towing with your vehicle, you will need a trailer wiring harness made for your vehicle. I recommend the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # TK77FR as it does not require splicing into your factory harness, which makes for a clean install. I included the install video for the Curt # C13387 and a video for the Tekonsha Harness...
    view full answer...
    Image 1 for
  • Trailer Hitch Recommendation for 2022 BMW X3
    Yes we do have a hitch for your 2022 BMW X3. I would recommend the Curt hitch part # C13387 which is mostly hidden and has the best towing capacities. I attached an install video and a picture of what it looks like installed. If you need trailer wiring too you'd want the Tekonsha kit part # TK77FR which installs easily and has a very reliable converter box.
    view full answer...
    Image 1 for
  • Recommended Trailer Hitch Receiver for Towing With 2022 BMW X3 M40i
    For a hitch to tow with your 2022 BMW X3 M40i I recommend the Draw-Tite Max-Frame Trailer Hitch Receiver # 76226. This hitch has a concealed cross tube so you will only see the receiver tube hanging down at the back of your vehicle. It is a Class III hitch with a 2" receiver. It also has a max gross trailer weight of 5,000 lbs and tongue weight of 750 lbs. It features a bolt-on installation and a limited lifetime warranty. For the most reliable wiring harness, you need the Tekonsha T-One...
    view full answer...
  • Trailer Wiring Recommendation for 2012 BMW X3
    For your 2012 BMW X3 we only have universal style trailer wiring harnesses available like the ZCI kit part # 119250KIT which does not require splicing as it uses sensors instead. I attached an install video that shows a similar kit install on an X3 like yours to show you how to find the correct wires.
    view full answer...
  • Hitch and Trailer Wiring Recommendation for 2021 BMW X3
    The Curt Hitch part # C13387 is a great option for your 2021 BMW X3 31i for towing a small trailer and since Curt has the most durable powder-coat it would be the best option to prevent corrosion as well. Then for trailer wiring you'd also need the Tekonsha kit part # TK77FR would be the way to go as it's easiest install and most reliable.
    view full answer...
  • Installation Location for Draw-Tite Max-Frame Trailer Hitch Receiver on 2020 BMW X3
    You can find a local installer using the link I have added below. Our product pages also have a "Locate installers near me link" that allows you to find results based on your zip code. I went ahead and added Albany, NY to the link so you can find someone to install the # 76226 on your 2020 BMW X3. If you want wiring installed as well for towing, you will also need the T-One Vehicle Wiring Harness # TK77FR. If you need a ball mount, check out the etrailer Ball Mount Kit # 989900. This...
    view full answer...
  • Recommended Trailer Wiring Harness For A 2021 BMW X3 xDrive 30i
    When it comes to installing a trailer wiring harness onto your 2021 BMW X3 xDrive 30i we do offer The Upgraded Heavy Duty ModuLite Circuit Protected Vehicle Wiring Harness with Installation Kit # 119190KIT as a splice in wiring option. This harness will work on vehicles and trailers with either LED, incandescent, or standard bulb tail lights. I would still recommend The T-One Vehicle Wiring Harness # TK77FR over the splice in option. This harness will plug into your vehicle's wiring harness,...
    view full answer...
  • Availability Of Trailer Hitch Receiver For 2022 BMW X3 M40i
    There sure is! For your 2022 BMW X3 M40i you will need to go with the Draw-Tite Trailer Hitch Receiver # 76226 as it is compatible with your M40i model where the # C13387 you were looking at is not. This hitch is a great choice for your vehicle as its hidden crosstube design makes it so only the receiver itself is visible once installed as you can see in the included picture. It looks like you were looking at towing accessories so if you will be towing a trailer with your X3 you will...
    view full answer...
  • Compatibility of Draw-Tite Hidden Hitch Trailer Hitch Receiver With Hands Free Liftgate 2018 BMW X3
    You will still be able to use the hands free liftgate feature on your 2018 BMW X3 M40i with the Hidden Hitch by Draw-Tite Trailer Hitch Receiver # DT56GR. We tested the hands free feature on a 2021 X3 with the similar Draw-Tite Max-Frame Trailer Hitch Receiver # 76226. I have linked the video below and you can see it operate at the 4:00 minute mark of the video. As these two receivers are made by the same manufacturer with similar placement you will have the same result with your receiver. I...
    view full answer...
  • Trailer Hitch Fit for BMW 2021 X3
    According to the linked installation instructions, no reprogramming is required to install the Draw-Tite Class III hitch, part # 76226. The hitch is a fit for all models of the 2021 BMW X3 xDrive 30i and M40i. Sometimes, if a dealer installed trailer wiring harness is installed, the vehicle computer will need to be re-flashed, but the same isn't true for aftermarket trailer wiring which are designed to stand alone. If you'll be towing with the hitch, you'll also need a trailer wiring...
    view full answer...
  • Hitch Install for 2021 BMW X3
    We actually have a feature on the web page for the Draw-Tite # 76226 that can be used to locate a local installer. Simply use the provided link and input your zip code. The Draw-Tite # 76226 is a fit for selected 2011-2022 BMW X3 models. If you'll be using the hitch for towing purposes, you'll also need a trailer wiring harness like part # TK77FR which is compatible with the 2018-2022 BMW X3. You'll also need a ball mount like # D-28, a hitch pin like # PC3 and # 19260 for a 1-7/8 or #...
    view full answer...
    Image 1 for
  • Recommended Trailer Hitch Receiver and Swing Away Bike Rack For a 2021 BMW X3
    I recommend going with the 2" mounts whenever possible. The 2" hitch has a larger selection of options for you to get the bike rack that you prefer. The RockyMounts BackStage Bike Rack # RKY10002 has what you are looking for. It comes with a swing away built in so you will be able to move your bikes to access the rear cargo area. It uses a wheel mount so it will not risk any damage to your carbon frames. If you are in need of a receiver for your 2021 BMW X3, I recommend the Draw-Tite...
    view full answer...
  • Trailer Hitch and Wiring Recommendations for a 2019 BMW X3
    We do have some trailer hitch and wiring options for your 2019 BMW X3. For a hitch I recommend using the Draw-Tite Class III # 76226 as it fits all models of your X3. Then for wiring you'll need the T-One # TK77FR which tees in behind your tail lights and gives you a 4-Way for basic lighting. To add the correct 4-Way and 7-Way connectors we will need to determine the purpose of having those sockets. We can mount the sockets to our receiver using the Easy Mount Bracket # C58000, but you...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jameson C
Expert Research:
Jameson C
Employee Kathleen M
Installed by:
Kathleen M
Employee Chris R
Video Edited:
Chris R
Employee Wilson B
Updated by:
Wilson B
Employee Alexander C
Written by:
Alexander C
Employee David F
Test Fit:
David F
Employee Thomas T
Video by:
Thomas T

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