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  1. Custom Fit Vehicle Wiring
  2. Hopkins
  3. Trailer Hitch Wiring
  4. 4 Flat
  5. Custom Fit
  6. No Converter
Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Item # HM42115
Our Price: $31.90
Custom Fit Vehicle Wiring

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Custom Fit Vehicle Wiring HM42115 - 4 Flat - Hopkins
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Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring - no cutting or splicing required. 1-800-940-8924 to order Hopkins custom fit vehicle wiring part number HM42115 or order online at Free expert support on all Hopkins products. Great prices and Fastest Shipping for Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
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  • Reviews (47)
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Hopkins Custom Fit Vehicle Wiring - HM42115

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

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring - no cutting or splicing required.


  • 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
    • Locate connection points behind rear bumper
    • Plug in connector
  • Protective connection terminals resist corrosion
  • Comes with dust cap for 4-way flat connector, cable ties, and terminal grease packet for electrical connections
  • 90-Day limited warranty


This custom-fit T-connector plugs into your vehicle's wiring harness, which is located behind your rear bumper, on the driver's and passenger's sides.

Once installation is complete, the 4-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 4-pole connector itself - to help prevent corrosion.

42115 Plug-in Simple Hopkins T-Connector with 4-Pole Trailer Connector

Installation Details HM42115 Installation instructions

This Product Fits The Following Vehicles

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - HM42115

Average Customer Rating:  4.8 out of 5 stars   (47 Customer Reviews)

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring - no cutting or splicing required.

2000 Dodge Ram Pickup

I am giving this rating based on the lack of clarity in the instructions. Some illustrations would also have been helpful, or perhaps a youtube video. I have not installed it yet. The green wire appears too short and I will need to strip it off the main harness. When I attmepted this on another Hopkins harness the attached wire pulled the insulation off. So we'll see how that goes.

1998 Dodge Ram Pickup

fits and performs perfectly



I use my small trailer 10-15 times a year. the wiring works flawlessly. It was a simple easy install

2001 Dodge Dakota

Worked perfect on my truck.

2000 Dodge Dakota

As easy as they said to install. And they look great. I showed it to a friend of mine and he like them and he's going to get him for his truck.



It works great..easy installation good product.. recommend. I just ordered another one for my 2004 Dodge Dakota should be getting it today...

2002 Dodge Dakota

Installed with ease, just enough grease for the job and self tapping screw for the ground, zip ties and a cover!

1999 Dodge Ram Pickup

I needed this wiring harness right away and paid almost $11.00 extra for USPS Priority Mail with 2 to 3 day delivery instead of the $2.99 standard delivery. It was sent by ground UPS which was problem since I live on the other side of the country, UPS are slow as snails. I called customer service and they admitted it was a mistake. They refunded my shipping costs which is nice but the late arrival of my item really messed up my trip. Mistakes happen, they handled it as best they could...all is well.



Working fine after 1 year. Thanx


It was a super simple to install!! Just unplug factory plug and plug it into hopkins wiring harness. Then plug in the factory plug that runs to the rear brake,and turn signal throw couple zip ties to make the wiring look clean. Then mount the 4-pole flat trailer connector into 4-pole flat bracket holder which they sell here at etrailer well worth the $5 dollars it cost

1995 Dodge Ram Pickup

This product was so easy to use took me less than 5 minutes to hook it up I just put some electrical Grease in the plugand plug it in that easy

2001 Dodge Dakota

Product fit as it was supposed to do. There was no problem attaching the wiring harness to my vehicle.
It was delivered on the date stated and in great condition.

Thank you for your timely delivery and the product you sent.


This was exceedingly simple to install! I would highly recommend this product to anyone looking to add a wiring harness.

1999 Dodge Dakota

Perfect fit to my 99 dodge Dakota. Sport ext cab 4x4. Note to self for future installations....wear glasses or googles to avoid dirt in eye when you get under for those connections.

1998 Dodge Ram Pickup

Easy to find the exact harness for my 98 Dodge P. U. Received it in a timely fashion. Works perfect for my boat trailer.

2001 Dodge Ram Pickup

Exactly what I ordered. OEM spec on 2001 Dodge Ram 1500 direct connect trailer light hook up. Arrived early.


Easiest install of any wiring harness I have ever used. Highly recommend. Installed in less than 10 minutes.


Excellent wiring harness very easy to hook up

1998 Dodge Ram Pickup

Makes wiring for 4 pole connector super simple. Just plug into factory wiring, ground it, and your all set.

1997 Dodge Ram Pickup

Great harness kit, gives you everything you need, with diagrams. Installed it on a 1997 dodge ram 1500. Couldn't been easier. Thank you.

2001 Dodge Ram Pickup

great product fast and easy shipping only took 10 minutes to plug and go..thanks

1999 Dodge Ram Pickup

Pluged right in just like expected, no cutting wires needed. Just screw the ground wire down and thats it . 5 minute intall

1999 Dodge Ram Pickup

Pluged right in just like expected, no cutting wires needed. Just screw the ground wire down and thats it . A 5 minute intall





It is working fine, no problems.

1999 Dodge Dakota

awesome place to do parts ordering, Quality products and easy install

1998 Dodge Dakota

Product as ordered and fast shipment. Thank You.



Still working great


An excellent product, well made and at a very reasonable price for a custom made product.
It was exceptionally easy to install and has worked without issue ever since.


Good Quality Product. Great Fit. Prompt service. Thanks

Show More Reviews

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

  • How Does Hopkins Trailer Wiring Harness Install on a 1997 Dodge Dakota
    There is no cutting, splicing, or soldering required. To install trailer wiring harness # HM42115 on your 1997 Dodge Dakota you will first locate the vehicle factory tail light wiring harnesses behind the rear bumper. These harnesses should have the same connector ends as the Hopkins Wiring Kit. Disconnect both vehicle factory connectors by lifting up on the release tab located on top of each housing. One is located on the driver’s side, one on the passenger side. Plug the Hopkins vehicle...
    view full answer...
  • Installing a 7-Way Trailer Vehicle Connector on a 1999 Dodge Ram 2500
    The Pollak Replacement 7-Pole, RV-Style Trailer Connector Socket for Dodge/Chrysler # PK11893-11933 will fit 1999 Dodge Ram 2500's that came with a 7-way connection from the factory. The 7-way socket will require drilling of new holes as it does not match the OEM bolt pattern. If your Ram did not come from the factory with a 7-way you will need the Hopkins Plug-In Simple Vehicle Wiring Harness # HM42115 along with a Universal Installation Kit for Trailer Brake Controller # ETBC7. This...
    view full answer...
  • How to Activate Reverse Light Circuit of Reverse Lock Out with 4-Way HM42115
    The # HM42115 is a 4-way which does not carry the reverse light circuit like what the part # T4748800 needs for activation. What you'd need to do is use a 4 to 5-way adapter like part # 20036 so that you'd have the fifth circuit available to run to the reverse light circuit of your vehicle. You'd have to tap into the reverse light circuit of the vehicle by tracing the wires that lead to the reverse lights and testing the wires for voltage when the reverse lights come on.
    view full answer...
  • Adding a 7-Way Trailer Connector to a 1998 Dodge Ram Pickup Laramie V8 Magnum
    I did some checking and the part of # PK11893-11933 with the square connector is not listed as a fit for the 1998 Dodge Ram trucks. The way to add a 7-Way would be to use # HM42115 to first add a 4-Way and then use # ETBC7 to add a 7-Way, retain use of the 4-Way, and have the wiring and accessories needed to install a brake controller if needed. I have included some links that show and explain the ETBC7 installation for you. If you also want to add a brake controller I recommend # 90885...
    view full answer...
  • 7-Way Trailer Wiring Recommendation for 2002 Dodge Ram 1500
    We have just what you need. For a replacement 7-way that is designed to fit the factory wiring of your 2002 Dodge Ram 1500 the Hopkins kit part # HM42190 would be an excellent option.
    view full answer...
  • Parts Needed to Install Curt Brake Controller on 2001 Dodge Dakota without Tow Package
    We do have everything you need to install your Curt Venturer Brake Controller # C74VV to your 2001 Dodge Dakota without the factory tow package. If you don't yet have a trailer connector at the rear of the truck, you will need to start with a 4-Way connector. For this I recommend the Hopkins Plug-In Simple Wiring Harness # HM42115. This custom harness is confirmed to fit your Dakota and will install by plugging directly into factory ports behind the rear bumper. I have attached the installation...
    view full answer...
  • What is Needed to Install Curt Echo Brake Controller in 1998 Dodge Ram?
    There are a number of things you will need in order to install the Curt Echo Brake Controller # C51180 on your 1998 Dodge Ram. It does not sound like you had a factory connector so you will need to start with 4-Pole Flat Trailer Connector # HM42115, and then Installation Kit # ETBC7L, which includes the necessary wiring, circuit breakers and 7-way and 4-way connector to hook up the brake controller. Your Ram is not going to require any type of relays, and as for diagrams, I have linked...
    view full answer...

Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Jeff D
Installed by:
Jeff D
Employee Alexander C
Written by:
Alexander C

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