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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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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 7 Pole to 4 and 5 Pole Adapter Review

Today we're going to be taking a look at the Hopkins 7-pull to 4-pull and 5-pull adapter, Part Number 37385. This Hopkins wiring adapter is made from a nice solid plastic and converts your 7-pull adapter into a 4-pull and 5-pull, so you can use this for anything from your wiring harnesses on your towing vehicles or boat trailers. To use it, you just pull back the dust covers here, which are nice because it keeps all the dirt and grim out of it while you're driving, and plug in whatever accessory you have. Now that we've gone over some of the features of it, let's show you how it installs. We go to our 7-pull back here, open the cap and put our adapter in place. Now you're ready to use your 4-pull or 5-pull. There you have it for the Hopkins 7-pull to 4-pull and 5-pull adapter, Part Number 37385..


Customer Reviews

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

Average Customer Rating:  4.9 out of 5 stars   (83 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:

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. 408502


Comments
After one year the wiring adapter continues to work well. I would not change my original review.
Capt.Wanabe - 07/23/2018

41332

- 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:

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



- 37385
by:

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



- 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:

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



- 37385
by:

Worked great. Just as advertised. Super simple converter. 521414



- 37385
by:

This adapter works great and still functions like new after one year. 520871



- 37385
by:

My order came on time and the product is great. The Tech support was great this is my new go to place for all my parts now. 508781



- 37385
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. 493530


Comments
Working great, I am causious about not losing it again, thanks again.
Jimmy - 04/07/2019

52571
25
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Show More Reviews

Ask the Experts about this Hopkins Wiring

  • Bypassing TIPM for Trailer Wiring Fix on 2004 Dodge Ram 1500
    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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  • Troubleshooting Trailer Wiring of 2004 Dodge Ram that Stopped Working
    Looks like you have a mid-2000's Dodge Ram truck which uses a TIPM setup for controlling the trailer taillights. This is similar to a fuse box or relay box but only Dodge can service it. When you short out the TIPM you have to take it to a dealer so that they can reset it, and they will only do this so many times before you have to spend a ton of money to replace it. The best way around the TIPM is to bypass it all together with the trailer wiring. For that you can use the wiring...
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  • Converter to Provide Brake-Only Signal for 3rd Brake Light on Camper Shell
    A center or 3rd brake light needs to receive a brakes-only signal. You will need the Pacer Performance 3rd Brake Light Logic Module # PP20-702 to block the turn signals. This is needed when using an LED 3rd brake light.
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  • Front Lights on Trailer Work But Rear Lights Dont Work and Get Hot
    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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  • Recommended Parts for Re-Wiring 5-Pole Flat Boat Trailer to Match Truck 7-Way Wiring
    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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  • 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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  • Brake Light Troubleshooting with Modu-Lite Wiring Harness
    There are a couple troubleshooting steps we should try out on your # 119179 , but I think we can isolate the issue down to one probable cause. First, make sure you're testing the smaller red wire (which connects to your brake lights) for voltage; the larger red wire is going to be the power wire that is connected to the battery. You also need to make sure that your ground is connected firmly to a clean, paint free surface. If you can confirm that these are both the case, the converter is...
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  • Trailer Running Lights Malfunction When Towed with Ford F250
    Since the problem is only occurring with one of the vehicles, the problem likely lies in the wiring of the trailer connector of your F250. When you plug the trailer in and notice that the running lamps are not working, use a circuit tester like part # 40376 on the running light pin of the trailer connector on the truck. I've edited a photo for you showing the running light circuit on a 7-way and a 4-pole trailer connector. If you are using an adapter, first test the connector, plug the...
    view full answer...
  • Uhaul Trailer Wiring Harness Causes Brake Light and Blinker to Not Work on 2009 Chevy Impala
    The wiring harness used on your 2009 Chevy Impala must not be grounded properly or it is possible that there are bent or broken pins in the harness they used. The ground needs to be attached to clean and corrosion free bare metal surface. There can't be any paint or coating either. Check the connectors for the harness to see if there are any bent or broken pins. A bent pin might be able to be bent back but if a pin is broken the harness will need to be replaced. I recommend # 118417....
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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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  • Converting a 4-Way Flat to a 5-Way Flat Trailer Connector on a 2006 Toyota Sequoia
    There are a couple of ways you could add a 5-Way flat to your 2006 Toyota Sequoia. I recommend a more direct method. You can use the Adapter 4 Pole to 5 Pole Trailer Wiring Adapter, # 20036. One end plugs into the 5-Way on the boat trailer, the other end plugs into the 4-Way on the vehicle. The 4-Way end has an additional wire for the extra function that is on the 5-Way end. If the extra pin on the trailer is used for an electric reverse lockout, you would connect the blue wire to the...
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  • Trailer Turn Signal and Brake Lights Dont Work But Running Lights Do
    Even if you have checked all of the connection points and fuses, there could still be a short in your wiring somewhere along the line. If you put proper protection on your soldering, the best protection would be using Heat-Shrinkable Tubing # DW05449 with Electrical Tape wrapped around the places that you soldered, then your splices should be okay. Otherwise the connections could jar loose, or in cold conditions they could become brittle and ineffective. If your connections look good,...
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  • Troubleshooting Tow Package Wiring of 2001 Chevy Silverado
    Since the truck lights are working okay, I'd sincerely doubt the problem lies with the turn signal stalk assembly. If this WERE the problem, the brake lamps on the truck wouldn't work either. My guess is that there's a problem somewhere in the tow package wiring. I'd recommend going into the fuse box in the engine compartment and checking the following fuses- STOP LP, CHMSL and VEH STOP. If these fuses aren't blown, the problem would lie somewhere else in the tow package. Rather than...
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  • Installing a 7-Way Trailer Connector and Brake Controller on a 2006 Ford Expedition
    On your 2006 Ford Expedition, there should already be a factory installed trailer connector. It will either be a 4-Way flat or a 7-Way blade. If your vehicle has a 4-Way flat, you will need to add Adapter 4 Pole to 7 Pole and 4 Pole, # 37185. On this connector, you would plug your 4-Way into the corresponding plug on the adapter. The remaining wires would need to be hardwired. Take a look under your vehicle behind the driver side rear tire and the bumper for the trailer wiring. There will...
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  • Troubleshooting Trailer Brakes That Engage When Silverado Running Lights Are Turned On
    There are several potential causes for your issue. You could have a corrosion problem in either the vehicle trailer socket or the trailer plug. Because of the many circuits in a 7-way connector it is possible for corrosion, dirt or moisture to bridge two adjacent circuits together. When this happens one function leaks over to the wrong pin. If for example a running light circuit became bridged to the trailer brake circuit the brakes would engage whenever the truck's lights were on. Inspect...
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  • Only the Left Trailer Brake Light Does Not Work on a Big Tex Trailer
    This sounds like a ground issue. Ground problems normally show up when there is more draw on a system such as when you have the running lights on and then use another function like a turn signal or brake light but can pop up anywhere. Make sure that the vehicle side and trailer side connectors are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces. The light grounds should also be attached to clean...
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  • Why Would a Right Trailer Taillight Stay on After Vehicle is Turned Off
    Typically when a trailer function stays on after the vehicle has turned of the problem is a fried aftermarket 4-way converter box. Or, if the lights are LEDs sometimes you will see the lights dimly lit. If you have an aftermarket 4-way converter box installed for trailer wiring on your vehicle most likely it has shorted out. Check out the video I attached that details how to test it. These don't usually short out for no reason, before you replace the harness you will want to find...
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  • No Running Light Power on Truck Side 4-Way Trailer Connector
    If there is no power on the truck side trailer connector running light circuit then it could be a blown tow package fuse or a loose connection, damaged wire, or ground issue. If the connector on the truck is factory then consult the owner's manual to locate the fuse related to the tow package running light circuit. You can also check the vehicle side connector for corrosion inside, where the wires attach, and outside on the pins. Inspect the wiring as best as you can from the connector...
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  • Boat Trailer Turn Signals and Brake Lights Work But Not Running Lights
    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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  • Plugging in a Tow Dolly and Magnetic Light Kit to the Same 7-Way Trailer Connector
    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 a TrailStar Trailer that Running Lights Only Work on the Left Side
    It sounds like the problem is in the way your left side tail light is wired, does your left turn signal work? I would go over the wiring and make sure that the brake/turn signal wire is attached to the correct circuit of the light and the tail light function is connected to the other. It almost seems like you might have both trailer light circuits run to one circuit of the tail light. I attached an FAQ article on trailer wiring for you to check out also that might be helpful.
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  • Troubleshooting Common Trailer Wiring Issues on 2004 Chevy Suburban & 2006 Cadillac Escalade
    That's a tough one, indeed. Usually we can isolate the cause for a wiring problem by substituting an alternate vehicle or trailer. My initial suspicion is that both vehicles have a ground problem. A weak ground will allow some lighting functions to work while others may not. I suggest you check the white ground wire for each vehicle's wiring harness to ensure these are tightly affixed to a clean bare metal spot on the frame. If the grounding points are rusty/greasy clean and sand them...
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  • Only Left Side Brake and Turn Signals Working on Boat Trailer
    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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  • Trailer Lights are Erratic After Switching to LED Lights
    Jesus is a good driver, but not a trailer expert. And that's ok because your trailer is not possessed . . . well, it could be, but that is not what is causing this problem. What you have here is a ground problem. Ground problems can cause all sorts of funky things to happen. The good news is ground problems are usually very easy to fix. The bad news is that you have to find the problem before you can fix it. Ground problems normally show up when there is more draw on a system such as...
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  • Trailer Running Lights Will Not Work and Blow Fuse on Truck
    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...
    view full answer...
  • 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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  • Troubleshooting 4-Way Harness On 2013 Ford F-150 And Trailer Wiring
    If you installed the 4-way connector at the back of your 2013 Ford F-150, you can check the connector first to make sure it is wired correctly. I recommend using a circuit tester like part # 40376 and check each pin for function. You want to make sure the pin connected to the yellow wire shows current for your left turn and brakes, green is for right turn and brakes, brown is for the tail lights, and the white wire is the ground which should be secured to a clean, bare metal surface. You...
    view full answer...
  • Trailer Brake and Turn Signals are Not Working but Running Lights Work
    If you are using an adapter like # 37385, it could be that the adapter is not pinned out the same way as your trailer requires. What you can do is test the functions on the trailer connector on your vehicle with a circuit tester like # 40376 if needed to make sure that all of them are working properly. If they are then you know the problem is behind the vehicle side connector. If they are not working properly on the tow vehicle it could still be a blown fuse or relays that needs to be...
    view full answer...
  • Troubleshooting Trailer Brake Lights that Go Out When Headlights are On
    There are two sets of grounds you need to check. The grounds for the taillight assemblies and the main ground for the trailer that runs from the trailer connector to the frame of the trailer. Between one of those grounds lies your problem as what your are describing is a textbook example of an insufficient ground. Another possible solution (although unlikely) is that you are overdrawing your trailer light circuits from your tow vehicle. You may have installed too many lights on the trailer...
    view full answer...
  • Troubleshooting Trailer Lights That Stop Working When Vehicle Headlights are On
    Your trailer taillights aren't sufficiently grounded. It sounds like your tail lights function until the additional load of having the head lights of your vehicle are turned on and then the lights cut out. Most trailer lights ground through the mounting studs if they do not have a ground wire on them. In either case, you will need to make sure the grounds are connected to clean metal surfaces on the trailer frame. The other ground to check is the one that runs from the trailer 4-way...
    view full answer...

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