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

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

Item # 118618
Retail:$114.94
Our Price: $76.81
You Save: 33%
Custom Fit Vehicle Wiring

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Shipping Weight: 1.94 lbs
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Custom Fit Vehicle Wiring 118618 - 4 Flat - Tekonsha
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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. Powered ModuLite reduces strain on wiring system. 1-800-940-8924 to order Tekonsha custom fit vehicle wiring part number 118618 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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  • Reviews (67)
  • Q & A (0)
  • Photos

Tekonsha Custom Fit Vehicle Wiring - 118618

  • 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 - no cutting, splicing or tapping required. 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 - no cutting or splicing of wires
    • Locate connection points in cargo area
    • Plug in connector
    • Run hot lead to car battery
  • 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: 4.2 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 your cargo area, behind the tail lights on both the driver's side and passenger's side. You will need to remove the access panel doors to access this harness. Once you've plugged in the T-connector, run the hot lead with the attached fuse holder up to your car battery. Connect the fuse holder to the positive terminal on the battery and insert the provided fuse.


T-One Connection Location Points Behind Tail Lights

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 an out-of-the-way location within your 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.



118618 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite

Installation Details 118618 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 - 118618

Average Customer Rating:  4.7 out of 5 stars   (67 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. Powered ModuLite reduces strain on wiring system.

by:

I have never installed a wiring harness that had a power pack. It was definitely more involved than a standard trailer, wiring harness, but the end result is definitely nice. The trailer lights are much brighter than they are when plugged in to my pick up truck, which has just the standard pigtail attached to the truck lights.



by:
Dodge Ram Pickup

This was very easy to install. One of our younger team members did the installation on our Ram Pro Master, quick and easy!



by:
Ram ProMaster 2500

Terri was so much help. The trailer hitch is on my promaster with the wiring all hooked up .
Thank you
Joe Restaino



by:

Incredibly easy to install. The videos were great. I installed the receiver hitch and wiring harness in about an hour. I just wish I would have ordered a mounting plate for the flat 4



by:

Hitch mounted up nicely, very happy with your product. Also the wiring harness was very easy to install. I will recommend your products to anyone who is looking to install a hitch on their vehicle.



by:

Easy installation and perfect fit plus excellent customer service! Can't say enough good things about etrailer.com



by:

a whole lot more work than other trailer plug wiring harnesses, having to pull a wire all the way to the battery in the front of the van, but that may be the van manufacturer’s (RAM) fault for not giving enough amperage allowance on the the tailight circuit to begin with. I would suggest getting this modification installed from the factory or the dealer if you have that option.



by:
Ram ProMaster 2500

The trailer hitch for a Promaster cargo van and the wiring harness I ordered with it are exactly as I expected, nice.
But the shipping, specifically the packaging was a problem. I found a very large box at my door that was split wide open, probably form the hitch smashing through from the inside. There was one small piece of cardboard stapled to the inside that was intended to keep the heavy steel hitch locked in it's corner, it failed. Luckily the UPS people were able to keep the unmarked wire harness box together with the hitch. The fasteners for the hitch were taped into the receiver so they stayed in place. This proves that one size box doesn't fit all. Hope you are listening etrailer?



by:
2018 Ram ProMaster 1500

Pretty easy install. Wires could have been a little longer. I mounted the module high enough to rout the tail light connector to the opposite side (Promaster high roof) then had to lengthen the trailer connector wires about a foot to get the plug located where I wanted it. Even with that though, the hardest part was getting the power wire discreetly routed to my battery. I have installed splice-in kits before, but this plug-and-play version was more convenient, even with the wire length issue.



by:
2014 Dodge ProMaster 3500

I have had no problems with my purchases. I bought a wiring harness and a trailer hitch. Both have worked out well. The hitch is a classA receiver hitch. It fit as expected and the wiring has kept the lights working right.



by:
Dodge Ram Pickup

The Curt trailer hitch receiver was so easy to install on my Ram Promaster 1500 that I was sure I had missed something as it only took about 20 minutes to install. It looks great also.
The customer service and shipping are probably the best I have come across in dealing with any company.



by:

Got the part, thank you!! Just need to install it been busy.



by:
2016 Dodge Ram Pickup

Lightning fast delivery! Perfect fit for my 2016 Ram Promaster 1500 Base. I opted to use wire nuts instead of the butt connectors for my installation.I ran the hot wire starting at the battery and worked my way back.and up into the top channel on the drivers side...



by:
2014 Dodge ProMaster 2500

Trailer hitch and wiring kit.
Not yet
installed. The hitch looks solid.
The wiring kit lacked instructions. None.



by:

A year later, no issues. I installed the harness through the inside of the van as opposed to outside along the frame. Much cleaner with maybe 15 minutes more install time. Check [online] for videos.



by:

The plug and play wiring harness was an easy install and works great.
Thanks



by:

Amazing product! Great customer service!
installed
on my customers vehicle and sent it down to FL, customer couldn't be happier!!!! the people at etrailer really care about you as a customer and they are really on top of their game. the only place i will ever use for vehicle products!



by:

Plug and play simple install.

James

3/4/2019

Still working great with no issues to date.



by:

After a year it's still holding even with extreme cold winter weather ..



by:
Ram ProMaster 2500

Ordered it and it arrived on time. Directions were easy with minor wiring knowledge required (crimping, wiring layout, securing).

Literally plug and play for the Promaster I drive. Worked first time!



by:

Perfect fit and easy installation. Easy follow instructions



by:

the product kit was thoroughly thought out and complete. The video instruction and personal service at etrailer make this business the best in the world



by:
2020 Ram ProMaster 2500

Great quality, perfect fit, easy instal lation.



by:
2014 Dodge ProMaster 1500

The hitch I buying is really excellent short and easy to install with a good explanation for the installation I'm satisfied a100% with the purchase



by:
2014 Dodge ProMaster 1500

The hitch I buying is really excellent short and easy to install with a good explanation for the installation I'm satisfied a100% with the purchase


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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 Jeff D
Installed by:
Jeff D
Employee Jacob T
Video Edited:
Jacob T
Employee Laura H
Updated by:
Laura H
Employee Wilson B
Updated by:
Wilson B
Employee Alexander C
Updated by:
Alexander C
Employee Isabelle B
Updated by:
Isabelle B
Employee Dustin K
Video by:
Dustin K
Employee Bradley B
Test Fit:
Bradley B

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