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Adapter 7-Pole to 4-Pole and 5-Pole

Adapter 7-Pole to 4-Pole and 5-Pole

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Trailer Wiring
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Adapter 7-Pole to 4-Pole and 5-Pole Multi-Function Adapter 37385
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Great Prices for the best trailer wiring from Hopkins. Adapter 7-Pole to 4-Pole and 5-Pole part number 37385 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (115)
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Hopkins Trailer Wiring

  • Wiring Adapters
  • Multi-Function Adapter
  • 4 Flat
  • 5 Flat
  • Plug Only
  • 7 Round - Blade
  • Hopkins


Features:

  • Wiring Adapter - converts the 7-way trailer connector on the vehicle to a 4-way or 5-way connector to match the trailer


If your truck has the connector on the left, and your trailer has one of the connectors on the right, you will want this adapter.
30300 18004
Vehicle End Trailer Ends


47385 Adapter 7 Pole to 4 Pole and 5 Pole - TAP # 37385

Item # 37385




California residents: click here


Video of Adapter 7-Pole to 4-Pole and 5-Pole

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Hopkins 7-Pole to 4-Pole and 5-Pole Adapter Review

Hey everybody, Ryan here at etrailer. Today we're gonna be checking out the Hopkins trailer wiring adaptor plug. So this is gonna go from a seven-way round not only to a four-way flat, but also a five-way flat. So let's check it out. And if your vehicle has a seven-way round type connector like mine does here, and you have to tow a trailer that has a four-way flat or five-way flat, this is gonna allow you to do that. So the way this will work is you'll plug into your seven-way round connector and then choose the appropriate type of wiring.

So we're hooked up to a small little fishing boat here. It has a four-way flat. We can open up that cap, take our trailer wiring, and plug right into it, and that's gonna allow all the signals to transfer back to our trailer, giving us all the lighting signals to keep us safe and legal. And what a lot of people like about this one is this honestly gives you the ability to tow or hook up to, wiring-wise, just about any trailer. So let's say maybe you have a utility trailer that has a four-way flat and then maybe a boat trailer that has brakes or something on it that has a five-way flat.

Having this one adapter is gonna allow you to pair up to all those different types and not have to keep two or three of these rolling around in your glove box or whatever the case is. These signals that this is gonna send back for our four-way flat will be your taillights, your brake lights, and your turn signals. So you have all your bases covered there. Five-way flat is gonna send out all those same lighting functions except that fifth pen is gonna be for a reverse light or backup circuit. Generally you'd see that on marine or boat trailers that are a little bit larger that have surge brakes, or even if maybe you have a utility trailer and you want to set up reverse lights on it, something along those lines.

That's where the five-way flat is gonna come into play. As far as the construction quality goes, I feel like it's pretty well-made. Feels like it's thick plastic, don't feel like a piece of junk by any means. It does fit nice and tight, at least into my seven-way. So that's good.

You know, don't worry about it having a loose connection or something, but I like how they give you the caps too because if you want to leave this thing in here, say if you tow a lot or something, or just don't feel like storing it inside the vehicle, at least you can keep those terminals protected against corrosion and whatnot. And honestly, from time to time anyway, it's not a bad idea to apply di-electric grease to 'em. And that holds true for your trailer end as well. Just keeps it in better shape and you can expect to get a little more life out of it. Something that I have ran into the past with using certain types of adapters is every trailer end might be a little bit different. These you don't see too often, but they are out there where they're kind of boxed in and in the past I've had issues getting 'em to hook up. And with this particular one, that's really not the case. It still fits right over it and creates a good tight seal. We do have a trailer here that has a five-way flat. And just to kind of show that off, you don't want to give the four-way all the love today. We'll just show you how it works too. You know, pretty standard connector and don't run into any issues in terms of getting that plugged in into our adapter plug. Other than that, at the end of the day, you know a great solution for those of you that have different types of trailers or different types of wiring, or if you're just unsure of what you might be pulling in the future. This is gonna allow you to hook up to all those different types for the most part. So can't really ask for too much more. But that'll about do it for our look-at of the Hopkins seven to five and four-way adaptor plug.

Customer Satisfaction Score:


Customer Reviews

Adapter 7-Pole to 4-Pole and 5-Pole - 37385

Average Customer Rating:  4.8 out of 5 stars   (115 Customer Reviews)


by:

You don’t often run into a flat 5-pole connector, but it’s nice to have it covered!



by:

The 4/5 flat adapter arrived as described. Very good quality.



by:

Wish I would have found this earlier, Super addition to my towing kit in my Atlas



by:

Great service.



by:

In my quest for a 7 pin to 4 pin connector to operate lights on my luggage rack my search led me to etrailer. Initially I spoke with Derek who was very helpful and sent me a connector that was 7 to 5 pin as that's what I thought I had. Turns out I was wrong so I called back to order a 7 to 4. This time I found Ashley and she quickly mailed me the 7 to 4.
These two employees were most helpful and very courteous in my dealings with them I'm happy to recommend etrailer for these kinds of products. Give them a try!

Jim L.

7/29/2018

Works fine. Only used it a few times but no problems.



by:

These plugs work great. I use it for my boat trailer (5 Plug), Jetski trailer (4 Plug) and a Car Hauler Trailer (7-way). Very simple to use. Highly recommend it you use multiple trailers with different plugs and braking systems.

Ted

9/10/2020

Everything is still working great with no issues!!



by:

Product was delivered in a timely fashion and matched the part ordered. Quality was excellent and provided the features per price point that was desired. So far, no problems in use. It is now part of my basic trailering kit. Other products are available that have more features but they are larger and cost more. For my use this is right on. Product support and useful information from etrailer is consistently excellent.

Capt.wanabe

7/23/2018

After one year the wiring adapter continues to work well. I would not change my original review.



by:

Provides a quick and simple solution for connecting a trailer with a flat-4 or flat-5 plug to my truck with its round 7-way plug.

Robin N.

7/21/2017

We recently towed a rental trailer from Maryland to New Mexico. This connector worked perfectly!



by:

Works well.



by:

Exact replacement for the one I lost, had no problem finding it at etrailer since I had previously bought hard to find parts I needed when replacing worn parts on my boat trailer. Thanks etrailer.

Jimmy

4/7/2019

Working great, I am causious about not losing it again, thanks again.



by:

Well made and reasonably priced.



by:

The adapter fit tightly and worked well. Be careful attaching and detaching the trailer harness so, you don't bend the bottom metal, male connector.

Everything installed correctly the first time and worked on my 2011 Honda Pilot. What a relief. It took me about 2.5 hrs because, I had to figure out fasteners for the bumper, existing wiring harness, etc. so I didn't break anything. Make sure you have a center punch, sharp metal drill bits and oil to pilot holes for self tapping screws. I am very happy with the harness and adapter.



by:

Was exited when I found this on etrailer's website...I have 2 different trailers with 2 differents light harness connectors. This works great...no need to switch out or have two or more adaptors in truck!! Highly recommend!



by:

Overall...much better than going through the dealership for the sake of time and money. The online videos hit all they key points and steps bit there was some mechanical ingenuity required on my part. Mounting the bracket was the most challenging part to install and it was correctly represented in other reviews.

Personally, I wanted the 7 pin connector flush to the bumper and had to bend the mounting bracket and cut out the plastic bumper to get a tight fit. Looking back however, I think that if I would have cut out just enough of the bumper to accommodate the angle of the mounting bracket (when attached to the frame) then I would have still achieved both a solid connection and clean, professional look.

All in all, I'm very satisfied with the product and instructions received from e Trailer and staff.



by:

It was great and worked exactly as it was supposed to until my dog pulled it out of the receptacle and chewed it to bits.
I put an external tire carrier on my car and was using the three hole side to power my relocated license plate.
The rig lasted through all sorts of weather and terrain like a champ. I got about 9 months out of it before it was devoured. I'm sure it would have lasted for years if not for the >-< dog.



by:

This adapter works perfect. It easily installs into the round 7 pin connector. The connector worked as all lights were lit and I was able to back my boat trailer into position with no problems. The 5 flat is used for the inclusion of the surge brakes on my boat trailer. I would recommend this to anyone needing the conversion adapter.



by:

Good product. Works well and is very convenient to have both 4 and 5 pin connectors. Only issue is dust cover on 5 pin sticks to ground pin when you pull it off with the tab and can bend the ground pin.



by:

As always, product arrived quickly and well-packed. Good quality and is working well on my vehicle. etrailer can be counted on for quality and customer service.

David

3/28/2020

No problems, never give it a second thought. Can depend on it to do the job.



by:

The Adapter made a quick and easy connection between my truck and the trailer. All lights functioned properly.

Great adapter at a great price.



by:

The wiring kit fits perfectly. I had a small problem with the operation of the brakes on my trailer but a quick call to the great service department and my problem was quickly rectified. I will do business again.



by:

I'm not one to take the time to write reviews but I just got to say this company really impressed me with the information available on their site and with the terrific service when calling them on the phone. In my experience this level of customer service is very hard to find today. Keep up the great work and thanks again for your time and help. I'll definitely recommend you and will be back should I have any needs in the future!



by:

Fits the round plug on the vehicle perfectly. Haven't hooked it up to the flat wire yet, but assume it should be fine. Getting this adapter with the covers for the 4 & 5 flat is absolutely the right way to go. I'm towing a 5500 lb boat with surge brakes.
Jesse did an outstanding job of helping me.



by:

Just what I needed, have a boat and two wheel trailer with different plugs , ordered the weather tech mud flats also for my 2011 gmc 1500, they were easy to install and look great, all items where to me in three days. Great job etrailer



by:

This trailer light adapter allows me to haul 2 different trailer with one vehicle. Delivery was in 3 days and I also purchased a 5 wire trailer wiring harness to match



by:

I find this adaptor to be very useful as I own and frequently tow, different size trailers all with different plug connectors. Nothing is worse than not having the right connection to make your trailer connection.


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Show More Reviews

See what our Experts say about this Hopkins Trailer Wiring

  • How To Convert a 4-Way To a 5-Way For Using Electric Lockout On Surge Coupler
    In order to utilize the electric lockout feature on your Tie-Down Engineering (TDE) Brake Actuator you will need to install the Hopkins Endurance 5-Way Flat Trailer Connector part # HM47910 on the trailer and the Adapter 4-Pole to 5-Pole Trailer Wiring Adapter part # 47515 on the vehicle if you have a 4-way. If you have a 7-way you will need to install the Adapter 7-Pole to 4-Pole and 5-Pole part # 37385 or the Hopkins Endurance Multi-Tow Trailer Connector Adapter part # HM47570 on the vehicle.
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  • Vehicle Wiring Harness For a 2013 Honda Ridgeline For a 4-Way Flat Trailer Connector
    It sounds like the Tekonsha OEM Replacement Vehicle Wiring Harness with 7-Way Trailer Connector # 118253 is the wiring kit you found for your 2013 Honda Ridgeline. Most people will choose to use an Adapter # 37385 to go from the vehicle 7-way to trailer 4-way flat connector. I find using the 7- and 4-Pole Trailer Connector Socket w/ Mounting Bracket # HM40975 as being the better option. This connector will replace the 7-way that is included in the Tekonsha Kit # 118253 and you will not...
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  • Troubleshooting Lack of Brake Lights on Trailer with Newly Installed 7-Way on Service Truck
    On your service truck, the 5 o'clock pin is for a brake controller output. There is not a light on this location, but just power to go to the trailer brake magnets. The trailer brake lights will run with the turn signal lights on each side. So you will have left turn and brake and right turn and brake. I've attached an article to assist. It sounds like you have a separate brake light on your service vehicle, so you will use the wiring converter like # C59236 to convert your 3 wire...
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  • Left Side Trailer Stop/Turn Signal Lights Not Working
    If there are no brake/turn signal lights on the left hand side of your trailer then the first thing you will want to do is check the fuse for that circuit in your vehicle's fuse box. It should tell you in the owner's manual where that fuse is located but if not it will be labeled on the underside of the cover/lid. After the fuse is checked you will then need to test the left hand brake/turn signal circuit on the vehicle side trailer connector. If no power is present then there is most likely...
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  • Will The 7 Pole to 4 Pole Adapter Fit My 2007 Toyota Tacoma
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  • Troubleshooting No Trailer Brake Lights on 2002 Chevy Silverado 2500
    It sounds like a short on that circuit somewhere deep in the harnesses of the truck. I wish there was an easy way to fix it. Typically it's just a blown CHMSL fuse on your truck which is VERY common with this problem. I'm actually shocked you checked that fuse and it's still good. Since other circuits are hit or miss it might be best to just bypass the factory wiring and wire in a converter box like the # 119250KIT which will wire to the factory wiring of the truck instead to get the signal...
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  • Troubleshooting Trailer Running Lights
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    Image 1 for
  • Trailer Has Separate Turn Signals that Come On with Brake Lights
    If the Coleman pup has separate turn signal lights then that is the issue. Trailers typically have what is called a 2-wire system with the brake lights and turn signals on each side sharing the same circuit and bulb. Either someone tried to install amber turn signals on the trailer but did not realize that it works on a 2-wire system, or they wired in the turn signals to the brake lights because the vehicle side connector had a 2-wire system and they could not operate the separate turn...
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  • Troubleshooting Boat Trailer Taillights that Work with Chevy Trailblazer but not 2013 Ford Edge
    It sounds like the problem is a weak ground on your boat trailer. I would check the grounds of the boat trailer and make sure they are attached to a clean metal surface of your boat trailer free of corrosion. Some vehicles are more sensitive to ground problems than others and that may be why one vehicle works while the other doesn't. I attached an FAQ on trailer wiring for you to check out.
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  • Troubleshooting Trailer Blinkers That Stay On or Don't Come On at all
    First thing you should do at this point is test the 4-way of the wiring harness with a circuit tester part # 3808 for voltage on all of the right pins when the taillight signals are being applied. Just like in the video I attached. If the voltage checks out there but the trailer lights still don't function right then the problem is on the trailer wiring. That would mean that problem is either due to a ground issue or a short issue. Make sure that the trailer side connector are clean and...
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  • Multiple Trailers Right Brake Lights and Turn Signals Not Working with 2003 Chevy Tahoe
    First, the easiest thing to check are the fuses related to the tow package wiring on your 2003 Chevy Tahoe. Check the owner's manual to find the fuse locations to check them. If the fuses are not the issue, then there is some testing you can do. Make sure that the vehicle side trailer connector is clean and free of corrosion at the pins and where the wires attach (if accessible). Then you can test the connector using a circuit tester such as # PTW2993. You will activate the function that...
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  • How To Wire For Lockout On Titan Coupler To Vehicle With 7-Way And Trailer With 4-Flat
    To connect the electric lockout on the Dexter Trailer Coupler, # 099-175-20, to your truck you will need to make sure the center pole of the 7-Way connector on your vehicle is wired to the reverse light circuit. If it is not wired to the reverse light circuit you will need to splice into the reverse light circuit behind the vehicles taillights and wire to the center pole inside your 7-Way vehicle connector. Once the 7-Way connector has the reverse light circuit at the center pole then...
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  • Troubleshooting Trailer Taillights that Stop Working When Brakes are Applied
    Sounds like you either have a weak ground on your trailer taillights or the lights themselves are drawing too much amperage and it's causing the circuit to just shut off. Typically a fuse would get blown if this were the case so most likely it's a weak ground. Also, be sure to check the function with the engine of the tow vehicle running as the additional amperage of the alternator running will give the trailer circuits a bit more juice.
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  • All Trailer Lights Work Fine Except Brake Lights Will Not Work
    On a trailer the brake lights and turn signals operate on the same wire/bulb. So, it is odd when the turn signals work, but the brake lights don't. There are 3 possible causes for this that are more likely than any of the other possible causes. First there could be a problem on the vehicle side. Use a circuit tester such as # PTW2993 to test the vehicle side trailer connector while someone steps on the brakes in the tow vehicle. If there is no power on any of the pins for this test then...
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  • No Left Turn Signal/Brake Light on Trailer Connector on a 2003 Dodge Ram 2500
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  • Troubleshooting Boat Trailer LIghts that Don't Function Properly when Headlights are On
    Most likely the problem is an insufficient ground on the trailer's wiring. Anytime you get bizarre trailer lighting functions like what you described when the headlights are on the problem is almost exclusively that the trailer light grounds can't handle the additional load put on the wiring when the headlights are on. Make sure that the trailer side connector are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare...
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  • Troubleshooting Brake Light/Left Turn Signal on a Trailer Towed by 1999 Chevrolet Silverado
    The first thing I would test is the trailer connector on your 1999 Chevrolet Silverado using a circuit tester like part # PTW2993 to see if the problem lies in the trailer or in your vehicle. See the linked video to see how to do this. You will be testing for brake/stop light functionality of the circuit and this will tell you if the problem is on the truck or the trailer. Also, to ensure that your trailer connector is wired properly, we recommend using the circuit tester to match pins...
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  • Converting a 7-Way Trailer Connector on Vehicle to a 5-Way Flat for Trailer with Electric Lockout
    I do have a way you can adapt the vehicle side 7-Way to the trailer so you can use the electric reverse lockout on the coupler. First, you will need an adapter that goes from a 7-Way to a 5-Way flat like # 37385. You will also need to make sure that the center pin on your 7-Way is wired to the reverse light circuit. On the trailer side, clip off the old 4-Way and wire in the Hopkins Endurance 5-Way Flat Trailer Connector, # HM47910. White is ground, green is right turn and brake, yellow...
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  • Recommendation for a 7-Way to 4-Way Flat For a 2011 Honda Pilot and Boat Trailer
    Yes, the Adapter 7 Pole to 4 Pole and 5 Pole, # 37385, will work with your 2011 Honda Pilot. We actually have several adapters that will work for you. I have included a link to them for you to view. If you do not have both a 4-Way and 5-Way trailer, which the 37385 adpater will accommodate, I would go with something a little more simple like the Pollack Adapter, # PK12716.
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  • Trailer Brake Lights Not Working on a Trailer Towed by 2008 Isuzu N-Series
    The turn signals and brake lights should be on the same circuit. What I think may be happening is when the brake lights are on, they draw more power. When more power is drawn, this is usually when you will see ground wiring problems. First, I would make sure that the vehicle side connector shows the same pin for turn signal and brake lights using a circuit tester like # PTW2993. Next, check to make sure both the trailer side and vehicle side connectors are free of dirt and corrosion. Then...
    view full answer...
  • New Boat Trailer Running Lights Do Not Work when Plugged Into Truck
    The 4-Way on your trailer sounds like it has a wishbone harness and is actually a 5-Way and not a 4 way. A wishbone harness will have 2 wires coming from the running light pin. The running light pin is the one right next to the ground pin. Everything should still function the same though. The 5th circuit is normally for a reverse electric lockout. What you will want to do is first test the vehicle side connector using a circuit tester such as # PTW2992 while some one sits in the truck...
    view full answer...
  • Adapting 5 Pole Flat Trailer Connector on Trailer to 4 Pole Connector on Tow Vehicle
    It sounds like you're wanting to tow a boat trailer that has an inertia operated surge coupler. All you'd need is a 4 to 5-pole adapter, like part # 20036. The extra blue wire on the vehicle side would tap into the reverse lamp circuit on your vehicle, so that when the vehicle's transmission is placed in reverse, the blue wire powers up and releases a solenoid in the trailer coupler which allows you to back the trailer without the brakes being applied. I've linked you to a video showing...
    view full answer...
  • Taillights Malfunctioning on Trailer Towed By Volvo VHD Dump Truck
    What kind of trailer are you trying to pull? A commercial dump truck likely uses a 7-way round pin trailer connector which likely has the right turn, left turn and brake signals separated into three circuits. If the trailer combines the brake and turn signal signals onto two circuits, one for right turn/brake one for left turn/brake, then you'll need to install a taillight converter onto the truck. This would explain why you've been having a heckuva time getting your trailer taillights...
    view full answer...


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