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7-Way Molded Trailer Wire Connector - 3' Long

7-Way Molded Trailer Wire Connector - 3' Long

Item # H20042
Retail:$35.49
Our Price: $28.36
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Great Prices for the best trailer wiring from Hopkins. 7-Way Molded Trailer Wire Connector - 3' Long part number H20042 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Hopkins Trailer Wiring - H20042

  • Trailer Connectors
  • Trailer End Connector
  • 7 Round - Blade
  • Plug and Lead
  • 0 - 5 Feet Long
  • Hopkins


Trailer Connector RV Style 7-Way Blade with 3' lead

  • Pre-wired 7-Way Trailer Connector
  • Measures 3 feet long including connector
  • Wire gauges:
    • 14-Gauge - red, brown, green, and yellow
    • 12-Gauge - blue
    • 10-Gauge - white and black


Wiring Code
Molded Connector Function Usual Trailer Wire
White Wire Ground White Wire
Red Wire Left Turn and Brake Yellow Wire
Brown Wire Right Turn and Brake Green Wire
Green Wire Tail Lights Brown Wire
Blue Wire Brake Power Blue Wire
Black Wire 12 volt (hot lead) Black Wire
Yellow Wire Aux. -



20042 7-Way Molded Trailer Wire Connector, 3' Long

Installation Details H20042 Installation instructions


California residents: click here


Customer Satisfaction Score:


Customer Reviews

7-Way Molded Trailer Wire Connector - 3' Long - H20042

Average Customer Rating:  4.6 out of 5 stars   (188 Customer Reviews)


by:

I've had this in use for over a year and they don't build them like they use to. I use this on a gooseneck trailer and the piece of plastic behind the spade connector for the clearance lights and brakes has melted, allowing the spade connector to lose contact with the plug on the pickup. So the lights would cut off in the middle of the night and would have to wiggle the connection till I could fix it. I have an older Hopkins plug and never had this problem.

To fix the problem I ended up putting pieces of thin copper wire behind the spade and have done it twice since the plastic melted a 2nd time and once again the trailer clearance lights would quit working. Attached are before and after pictures.



by:

After a year doing its job well.



by:

The product works great but the color coding is off compared to the colors on the trailer. I started hooking this up matching all of the colors.( Red on Red, Black on Black, etc.) When I plugged in the trailer in it blew a fuse. So I got online and found out that the Hopkins wiring is different then normal trailer wiring. Overall it works great but the colors should match to make it easier to hook up.

Etrailer Expert

Laura E.

7/22/2017

To ensure that your trailer connector is wired properly, we recommend using a circuit tester to match pins by function. Because wire colors can vary, they are not as reliable for determining functions. Improperly connected wiring can blow a fuse or cause damage to electric components. For more information, check out this helpful article:



by:

These connectors are of very high quality and make for a professional installation and appearance when used with LE$D lights and Dexter brakes. The different color of the wiring is a very minor obstacle. Using the wiring junction box really enhances the installation of the connector.

Lwal

5/27/2015

Connector is still working very well and expect to get unlimited years of service from the connector.



by:

These plugs are made so anyone could change them.



by:

Made nicely perfect length for my trailer. The trailer I'm using it on is only a 2 place enclosed snowmobile trailer that comes with your standard 4 flat I was tired of using adapters so I changed to this plug.

Jim B.

9/24/2014

That is exactly why I just ordered two pigtails. I am converting my 4 wire flat to a 7 pin and a 6 pin to a 7 pin. tired of trying to find adapters. I have 5 different trailer types and they will all have 7 pin when I am finished converting them.



by:

I bought an adjustable Curt receiver and my trailer wiring ended up being a few inches to short, it was tight to begin with. I was going to buy an extension but they were around 7' long, which was to long for my needs. I chose this and wired it up the other day and it works great so far. Make sure you have the RV blade type like this connector not the pin type or it won't work obviously. As mentioned in other reviews, the wiring may be color coded different on your trailer, so be mindful of that or you'll be re-doing the connections. It looks like a sturdy and well built sealed connector, so it should last for years and it was reasonably priced.

Etrailer Expert

Rachael H.

6/20/2018

We always recommend to test by function before connecting any wiring using a circuit tester like part # 3808. I have also included a link to one of our help articles that shows the different wiring configuration options.



by:

As with everything I have ever bought over the last 10 years from etrailer, never question the quality and service,they have always been there with great tech advice, fast shipping, and fair pricing.



by:

Wired to my Lance Camper harness to avoid having the Lance custom socket in the bed wall when I upgraded my truck. I had to run an 8 ga 12v source from the truck battery to the rear of the bed to supply lots of 12v power for the camper fridge. I didn't use the weak 12v supply from the stock truck trailer connector.



by:

These connectors were high quality by a known manufacturer. I could have bought them locally but I wouldn't have gotten the expert advice and detailed information that I was able to get from eTrailer!. I talked to several people and each one was very knowledgeable. When the parts arrived, it surprised me because they came so quickly! I would readily order from them again if I needed more trailer parts. I used these connectors to adapt a Minn-Kota trolling motor to my fishing kayak and have attached some pictures showing it installed.



by:

Wire color scheme was totally wrong for my Tundra, it’s a poor fit in the socket and it’s a touch too short. When I first hooked it up I had my running lights as blinkers and my reverse lights controlling my brakes. AVOID

Etrailer Expert

Mike L.

7/8/2019

There is more than one accepted wiring color code, which is why we identify the wire color and each wires function in the product description above.

Daniel

7/7/2020

Color schemes aside, this connector is intermittent after one winter. No physical damage can be seen but the cable needs to be bent a certain way for connection. Still 1 Star.



by:

You get exactly what is pictured. The 12v power and Ground (black and white) are 10 gauge, the "Aux" (which is red on this harness and purple on the ETBC7 vehicle wiring kit) is 12 gauge, and the other 4 wires are 14 gauge. The 3' length is measured from the face of the plug to the stripped ends of the seperated wires.



by:

After having our extension cable stolen and realizing the plug on the trailer was worn out and due for replacement, I decided to repair the end by adding a 3 foot pigtail. This accomplished both goals of adding cable length and replacing the plug end.
I used dielectric grease, butt crimp connectors and shrink tube to seal out the elements. Great product....



by:

Wow. Very heavy duty product at a reasonable price. I purchased this for an extension harness for my pickup because the connector on the truck is located way off to the side of the hitch. I expect this product to outlast my pickup.



by:

It's been working out for me I have two of them on my trailers



by:

Looks well made. I have no idea if it is made in USA though. I wish etrailer would give country of origin (when not USA). MAGA!

Dennis

5/11/2020

Good quality. Easy to work with.



by:

Product worked fine for what I needed. Plug on my tow vehicle was further away from the ball than it was on my old one. Trailer pig-tail was not quite long enough to provide slack for turns. I put the other end on this pig-tail and extended the trailer pig-tail. Worked great.



by:

Just installed the 7-way molded 3' trailer connector on an older Wells Cargo Inline Snowmobile Trailer and it fit perfectly. The molded end is going to work great keeping out the salty mist from our Wisconsin highways. The wire colors don't match trailor wiring standards, but the color key code on the web site was extremely helpful. With there fast and prompt shipping, I will be using etrailer.com from now on. Thanx



by:

Great connector, Holds up to years of daily use. Always had problems with the wire it yourself type connectors holding up to commercial use, After a few months the wires would get ripped out of them. We have standardized all of our company's (14) trailers to this seven way flat connector. It is the most reliable and secure one I have found.



by:

This is a well built product. The only concern that i have is that 3 of the wires are on the wrong circuit, even according to Hopkins' wiring diagram. The red, brown, and green are on the wrong circuits. Still usable as all are 14 gauge wires. All others are correct. Good product otherwise.



by:

Easy to install, I've had it spliced into my boat trailer for a year now and no issues. The body has held up well with no cracks or broken plastic pieces.



by:

Don't waste your time and money on this product. The pig tail was wired wrong so the larger gauge wires for things like 12v constant ground and the trailer brakes were on the smaller gauge wires and when the right turn signal was on it energized 4 other wires. I figured I would just re-arrange the wires in the pig tail and investigate why the right turn signal energized so many wires and to my surprise the plug was not accessible because it was molded around pig tail.



by:

Etrailer.com is the greatest online store for all your trailer and vehicle needs.
The item was shipped to my front door quickly and was exactly what I had ordered. I will always shop at etrailer.com whenever parts are needed for my towing needs.
Thank you etrailer.com!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



by:

Hard right turns with new truck pulled out camper electric connector just enough for some of the functions not to work. This fixed that problem. Needed some wire ends to make neat connections in the etrailer connection box. Used large zip ties instead of drilling to connect the box to trailer frame.



by:

Great one piece molded trailer wire connector to replace my 2 piece tore up connector. Excellent wiring diagrams available on etrailer.com as well.


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Show More Reviews

See what our Experts say about this Hopkins Trailer Wiring

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    Using the Adapter 4 Way Flat to 6 Way Square for Jayco Trailers, part # 30104, will provide lighting functions only. You will have turn signals, brake lights, and running lights. To gain connections for the other features like the reverse lights, battery charge, etc, your best bet would be to remove the connector on the trailer and install a 7-way connector. For the trailer, I would recommend the 7-Way Molded Trailer Wire Connector, part # H20042. When wiring this harness to the trailer,...
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  • Trailer Brakes Lock Up When Connected To Trailer Using 6 to 7 Pole Adapter
    The issue you are having with the trailer brakes locking up as soon as the trailer connector is plugged in has to do with the pin out of the trailer side trailer connector in relation to the adapter. The most likely problem is that the battery charge line is crossed with the brake output circuit. In order to fix this you will simply need to just swap out the two wires on the back of the trailer side trailer connector or you can just rewire a new trailer connector on the trailer using the...
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  • Best Way to Adapt a 7-Way Trailer Connector to a 5-Pole Round
    Replacing the connector on your trailer is probably the best way to go here. The connector you use will depend on what the extra circuit on the trailer does. If it is a boat trailer, and the extra pin operates the lock-out on a hydraulic brake coupler, using a 5-pole flat, part # 20017 along with a 7-way to 5-pole adapter like part # A75TB would be your best bet. If the extra circuit serves a different purpose, you would probably want to install a 7-way trailer connector, part # H20046...
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  • Adding Electric Drum Brakes to a Scamp Camper Trailer
    Setting up a trailer with electric drum brakes is going to be the easier and most cost effective way of adding brakes to your Scamp trailer. Since the trailer already has the mounting flanges that will limit the amount of parts and work that will need to be done. Starting with the hub and drum assemblies since your bearings are both L44649 and you have an EZ Lube style axle you would need # 8-257-5UC3-EZ with the 5 on 4-1/2 bolt pattern. They are designed for 2,000 pound axles but will...
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  • Charging a Tolling Motor when Towing a Boat with a 2005 Chevy Silverado
    Given that you currently have a 7-way on your truck, the easiest adjustments to make to your trailer connector would be to change the plug to a 7-way blade, and use the power lead of the new trailer connector to charge your battery. Use half of the wires to splice into the wires on your 4-way, ground the extra wire with the white ground, and run the power lead to the battery you wish to charge. You will need trailer connector part # H20042. If you already have the wiring to complete a...
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  • Electric Trailer Brakes for a Floe Snowmobile Trailer with 2,200 Pound Axles
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  • Wiring Adapter To Convert 13 Pin European Trailer Connector to 5-Way Flat Or 7-Way Blade Connection
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  • 7-Way Replacement Recommendation for Bunkhouse Camper with 6-Way Flat
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  • Functions of the White, Blue and Black Wires of the Replacement 7-Way H20042
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    view full answer...
    Image 1 for
  • How to Connect Horse Trailer with 6 Way Connector to 7 Way Vehicle Plug
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