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

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

Item # 37385
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37385 - Plug Only Hopkins Wiring
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Lowest Prices for the best wiring from Hopkins. Adapter 7-Pole to 4-Pole and 5-Pole part number 37385 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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Hopkins Wiring - 37385

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


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




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 Wiring - Wiring Adapters - 37385 Review

Today we're going to review part number 37385. This is the Hopkins 7-pole to 4-pole and 5-pole adapter. This is a wiring adapter that will convert the 7-way trailer connector on your vehicle to either a 4-way or a 5-way connector to match the trailer. As you can see the dust covers are included to protect them if you're not using the connector. Basically you'll notice when you plug this into the 7-way it'll give you your lighting functions on the 4-way. It has the ground, it gives you your tail light function, your left turn and brake, and your right turn and brake. On the 5-way, when you plug that in it will give you all the same functions of the 4-way but the extra one is for the reverse light circuit.

Lots of times on a boat trailer will use a 5-way so you'll be able to use that reverse light circuit for the surge actuator on the trailer itself. That should do it for the review on part number 37385, the Hopkins 7-pole to 4-pole and 5-pole adapter. .


Customer Reviews

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

Average Customer Rating:  4.9 out of 5 stars   (88 Customer Reviews)


- 37385
by:

Have used this adapter several times over the past year; works as advertised on our Tesla Model X, no problems, and it's well constructed. I would recommend this product. 545979



- 37385
by:

I have received the items I ordered from etrailer and expect to have them installed and used for the first time on 10/21. I can review them after 10/21. I was impressed with how fast my order arrived. 901707



- 37385
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. 894405



- 37385
by:

Excellent service 875352



- 37385
by:

I received shipping info on my adapter the day after my order was placed and it arrived quickly. I have not had a chance to use the adapter yet, but it seems very well made. Etrailer seems to really be focused on customer satisfaction. 872213



- 37385
by: 08/29/2020

Excellent product 871267



- 37385
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. 846108



- 37385
by:

This plug works great. 765069



- 37385
by:

Install in 20 minutes Great product Quick del8 737331



- 37385
by:

Got the fenders I needed, fast shipping, thought it was coming from east coast but came from more my region. Just what i needed however had to cut holes for the lights. These guys have done a good job for me a couple times now. Liking it. 717723



- 37385
by:

Great service, easy ordering. Love the adapter, no more rewiring to make plugs match. 711890



- 37385
by:

The quality of the product appears to be very good. I haven't had a chance to use it. 706584



- 37385
by:

Received item fast and does what it supposed to do. Would of given it a 5 star but on the adapter one of the pins not surrounded by mold was loose. Still works, I'm not paying to send it back and loose 1 1/2 weeks . 706517



- 37385
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. 699546


Comments
Everything is still working great with no issues!!
Ted - 09/10/2020

98793

- 37385
by:

Had what I needed with easy on-line ordering process. Received item about a week later 689947


Comments
Connector has been working well, no flickering trailer lights as connection is snug. Quality product
Mark D - 08/17/2020

97437

- 37385
by:

Great product and as usual, superb service. The reasons why I continue to come back again and again. 669088



- 37385
by:

Great service & Delivery Excellent parts, great customer service 666981



- 37385
by:

Everything I buy from etrailer is perfect Never a problem I would recommend To anyone #1 in my book 659241



- 37385
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. 635222



- 37385
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. 614687


Comments
No problems, never give it a second thought. Can depend on it to do the job.
David - 03/28/2020

71844

- 37385
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! 597517



- 37385
by:

as described, works excelent. etrailer is tops! 573010



- 37385
by:

Perfect fit, just what I needed to convert 7 pin connection on my Explorer to 5 pin connection on my trailer. 559395



- 37385
by:

Correct Parts Great Prices Fast Deliv ery 547737



- 37385
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! 527546


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Show More Reviews

Ask the Experts about this Hopkins Wiring

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    The TIPM setup of your 2004 Dodge Ram 1500 which handles your trailer wiring is a huge pain. At this point I would cut your losses with it and bypass it for the trailer wiring. All you will need is the Upgraded Circuit Protected Tail Light Converter Hardwire Kit # 119178KIT along with 4-Pole to 7-Pole Adapter # 37185 if you do not have a brake controller or # ETBC7 if you do have a brake controller.
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  • How to Power Rear Lights on Tow Dolly and Towed Jeep Cherokee Behind RV w/ 7-Way Connector
    I do have a solution for you, however there is not an adapter available that is able to convert your RV's 7 pole plug into two 4-way flat connections. The easiest way to power both the dolly and towed Jeep's rear lights behind your RV is to use the Hopkins Adapter 7-Pole to 4-Pole and 5-Pole # 37385. You will connect this to the 7-way connector on your RV and will be able to use both the provided connectors to send power to your dolly and towed Jeep's rear lights at the same time. The...
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    That definitely sounds like a ground issue. If your wires are hot and you are getting signals to the lights in front of them then you need to check your grounds. Not only do you have a main ground wire but each light itself will have a ground. Check to make sure that your grounds are secure and connected to a clean, bare-metal surface. If those look good then the only other thing would be some damaged wiring. Check from the working lights to the lights that don't work and look for any...
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    You technically could use # 37385 because a 4-Way flat connector will plug into a 5-Way flat receptacle. The last pin just isn't used on the 5-Way end. The only problem is that you have to make sure that the combined power draw is not too much for the tow package wiring on the tow vehicle. The other thing you can do is cut off the 4-Way on the magnetic kit and just splice it into the wiring for the tow dolly. But you would still need to be careful of the power draw. I do not anticipate...
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  • Troubleshooting 7-Way Trailer Connector on 2003 Chevy Tahoe
    Check that the harness that plugs into the rear of the trailer connector is pushed in all the way. I'd recommend using a circuit tester like part # 40376 on the wiring behind the trailer connector. If you're getting power on the harness but not on the trailer connector, the connector is faulty, damaged or corroded and would need to be replaced with a new connector such as part # HM40975. If you don't see any power on the harness, you'll need to check the fuse box under the hood. The...
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    Adapters like # 37385 and # HM47570 are convenient and can work fine for the short-term but for long-term reliability you are really better off replacing the connector on the trailer to a 7-way that matches your truck with no adapters - or their potential problems. Those extra connections can mean more chances for corrosion. You can easily test your truck's 7-way using a circuit tester like # 40376. Have a helper activate each function while you apply the tester to the appropriate pins...
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  • Adapting a 5-Way Flat Vehicle Side Trailer Connector to a 4-Way Flat for Towing Lights
    You may be able to plug in the 4-Way flat into the 5-Way flat without an adapter. There will just be one pin that is not used by the 4-Way left over. All the other functions will still work. The pin furthest from the ground pin (on the vehicle side 5-Way) will be the one that is not used. If the two connectors will not fit together, you can use Wiring Kit, # HM47890. You will just need the trailer side of the kit. You will have to replace the connector on the tow lights with the trailer...
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  • 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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  • No Left Turn Signal/Brake Light on Trailer Connector on a 2003 Dodge Ram 2500
    There is likely a blown fuse on your 2003 Dodge Ram 2500 that is causing the left turn signal/brake lights to not work. Use your owners manual or legends on the fuse panel lids to find the fuses related to the tow package wiring. Please note that there could potentially be more than one fuse for any given function so be sure to go through the whole list.
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  • Troubleshooting Trailer Brake Lights not Working When Running Lights are On
    It sounds like you might have a bad ground connection. When the taillights are on, that is when there is the most power draw on the system. Stepping on the brakes would then add more and this is when a ground problem will usually show up. The taillights usually ground through the mounting bolts on trailers. Check for a bad ground, loose connection, and dirt and corrosion. Any of those can cause this problem. Also check the light bracket connections to the trailer frame as lights can...
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    If the turn and brake lights on your boat trailer work but the running lights do not, then this does suggest a potential grounding issue. Turn and brake lights will generally draw less current since they do not remain on as running lights do so sometimes a marginal ground will let some lighting functions work normally while others do not. You can also check your two connectors for any signs of discoloration or corrosion that could be interfering with signal transmission. Even slight...
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    This sounds like a ground problem. A loose, broken, or corroded ground connection can cause all sorts of unwanted problems for electrical components including trailer taillights. I would start with checking for a proper ground at the taillight itself. Trailer tail lights can be grounded in one of two ways. The first way is the tail light assemblies can be grounded by a separate wire coming out of the back of the tail light and attached to the trailers frame. The second way is the tail...
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  • Troubleshooting a TrailStar Trailer that Running Lights Only Work on the Left Side
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    view full answer...
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    If it is the tow package running light fuse that is blowing then there is most likely a short in the trailer wiring or in the trailer or vehicle side connector. What you will want to do first is make sure both the vehicle side and trailer side connectors are clean and free of corrosion inside and out. Next make sure the main trailer connector ground and the grounds for all of the lights are attached to clean and corrosion free bare metal surfaces. Then you will need to trace the wiring...
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