bing tracking image
  1. Trailer Wiring
  2. Hopkins
  3. Trailer Connectors
  4. Vehicle End Connector
  5. 5 Flat
  6. Plug and Lead
Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long

Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long

Item # HM37908
lowest price pledge
Our Price: $13.58
Trailer Wiring
Orders above $99 qualify for Free Shipping
Shipping Weight: 0.31 lbs
In Stock
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

In Use/Installed

Need help with installation?
Locate installers near me
Wire your vehicle to tow a trailer with this universal, splice-in wiring harness. Provides reverse function to release surge brakes. Corrosion-resistant terminals are long-lasting. Lowest Prices for the best trailer wiring from Hopkins. Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long part number HM37908 can be ordered online at or call 1-636-306-4830 for expert service.
  • All Info
  • Reviews (8)
  • Q & A (0)
  • Videos (2)
  • Photos
  • Why etrailer?

Hopkins Trailer Wiring - HM37908

  • Trailer Connectors
  • Vehicle End Connector
  • 5 Flat
  • Plug and Lead
  • 0 - 5 Feet Long
  • Hopkins

Wire your vehicle to tow a trailer with this universal, splice-in wiring harness. Provides reverse function to release surge brakes. Corrosion-resistant terminals are long-lasting.


  • 5-Way flat trailer connector at the back of your vehicle plugs into the connector from your trailer to power your trailer's signal lights
    • Includes reverse function to release brakes when backing up
    • Ideal for use with marine-type trailers equipped with surge brakes
  • Simple installation
    • Hardwire to existing trailer wiring
  • Corrosion-resistant terminals are long-lasting


  • Harness length: 5'
  • Wiring configuration:
    • White: ground wire
    • Yellow: left turn/brake light
    • Green: right turn/brake light
    • Brown: tail lights
    • Blue: reverse lights
  • 90-Day limited warranty

37908 Hopkins 5-Way Flat Connector - Vehicle End - 60"

Video of Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long

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

Video Transcript for Hopkins Wiring Harness Review

Hey, everybody. Ryan here at etrailer. Today, we're gonna be checking out the Hopkins 5-way flat trailer connector for your vehicle side. For those of you that are unfamiliar with a five-way flat, this is essentially identical to kind of your classic four-way flat type connector. I'm sure a lot of people have seen them. They're just on about a ton of different medium size, smaller size trailers.

But this being the five-way though, you get one extra signal and that will be your reverse light signal. So, we have our ground wire, our taillight signal, our left turn as well as stop, right turn and stop, and this blue one is our reverse light. Now, there's a couple of different reasons you would wanna use this. I'd say probably the most common is for when you're towing a boat that has surge brakes on it. That way, when you're going to launch the boat or just even back it up into the garage or whatever, it'll have this reverse light signal and it won't lock the brakes up.

That way, you can actually back it up and not, you know, drag it across the ground. But you can kind of get creative too. I know there's some people that use this signal. They might have some small LED lights like as back up lights on their utility trailer and you can get a signal from this. That way, when you put it in reverse, it sends power out to whatever you have it wired up to.

So, you can kind of get creative on what you can do with this. Now, keep in mind this isn't gonna have a ton of amperage. So, you can't run a hundred lights off of it. But you got one or two lights on it, especially if they're LEDs, chances are good it's gonna power them right up and everything else. So, you know it's one of those deals that, in a sense, it's almost an upgrade over kind of your factory four-way or your regular four-way type connector.

And that kind of brings me to my next point. You are still able to use a four-way connector with this. So, let's say, if you have a boat trailer with the five-way and you also have the utility trailer with the standard four-way, you're still gonna be able to use the same connector. You won't need an adapter or anything. So, just for example, this is a trailer side, kind of your standard four-way and it'll still plug in. It'll still get its regular signals and everything else. So, like I said, you're not gonna need an adapter or anything like that. But I do want to mention, for this to work, you are going to need existing four-way wiring because this is essentially just a pigtail, right So, it's the connector and those five wires that come off of it. So, you are gonna have to kind of splice this into your existing wiring. And then, of course, you're gonna need to be able to find a way to pick up your reverse light circuit too. Whether it be your reverse light bulb, maybe your reverse light fuse in the dash or whatever, you're gonna need that power source, right So, that's just something to keep in mind whenever you're thinking about hooking this up to your vehicle. This particular harness is going to be five foot in length. So, changes are pretty good you're not gonna need all that wiring but it is good to have, right That way, if you do have to stretch it a little bit further, you got it, which kind of brings me to my next point. When installing this, it's probably a good idea, I would suggest picking up five heat shrink-type butt connectors, especially if you're gonna be keeping this outside since you have to splice in your existing four-way wiring. And it's gonna be pretty much the same for all vehicles. You splice in that four-way and then obviously, pick up your reverse light circuit, which like I mentioned earlier, you usually get it from your reverse lights, or one of your fuses, things like that. So, every vehicle is gonna be a little bit different but the idea is the same. I do wanna mention too, this isn't gonna come with a dust cover. You know how sometimes there's a little cap that'll plug over this So, that is something that you can grab separate and excuse me, you can also get, there's all different types of brackets and things of that nature where you can mount this up on your hitch. And this is even a good example. So today, I just put some of this black wire loom over our wires just to help kind of, kind of help it blend in a little bit better. So, you can use something like this as well if that's the style you're going for or the look you're going for. But other than that, at the end of the day, it's gonna be a good way to be able to use different types of accessories or pull those different types of trailers around that you otherwise wouldn't be able to. So hopefully, this kind of cleared up a few things and answered some of your questions on what this is, and what it actually does, and gets you going in the right direction. And that'll finish up our look at of the Hopkins five-way flat trailer connector for the vehicle side..

Customer Reviews

Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long - HM37908

Average Customer Rating:  4.8 out of 5 stars   (8 Customer Reviews)

Wire your vehicle to tow a trailer with this universal, splice-in wiring harness. Provides reverse function to release surge brakes. Corrosion-resistant terminals are long-lasting.


The product was good, but it took 45 days to get it.


The Glolight LED trailer set is the perfect replacement for my tow dolly. It is light weight and much more visible than the standard bulb lamp set the trailer was equipped with. Installation was quick and very easy, I will recommend this to all needing to change theirs out...


Just what I wanted. No frills straightforward ready to install. Good value and quality.


Thank you for shipping it out fast. Plan to use it for my motorcycle.


Haven't used it yet but pretty straight forward.


Good product. Would be even better if wire was tinned copper


Great product. Just what I needed.



See what our Experts say about this Hopkins Trailer Wiring

  • Solution to Activate Reverse Lockout Solenoid of Surge Brake Trailer Being Towed with Front Hitch
    This is a really good question. Probably the best solution would be to wire a 5-way to the front of your truck like with the part # HM37908. Run the blue wire to your positive battery post and then the white to the ground and whenever it's plugged into your trailer the reverse lock out solenoid will activate and allow the trailer to move.
    view full answer...
  • Subaru with 5-Way Flat Trailer Connector to Trailer with 4-way
    If your Subaru already has a 5-pole flat trailer connector like the Hopkins # HM37908, you will not need any additional parts to be able to connect with the 4-way flat on your trailer. You will just simply connect the two harnesses, and the additional pin on the Subaru's 5-way will just not be used.
    view full answer...
  • Connecting 4-Way on Motorcycle to 5-Way on Trailer
    I think what might be going on here is that your trailer uses separate wiring (which is what a motorcycle would typically use as well) but your motorcycle has combined wiring, or at least is equipped with a converter to combine it before the connector, which is why it's equipped with a 4-Way instead of a 5-Way. With a combined wiring setup the turn and brake signals on each side of the motorcycle are sent along the same circuit. This is why the lights aren't working correctly on the trailer...
    view full answer...
  • Will a Trailer 4-Way Plug Into a Vehicle 5-Way Without Adapter
    Yes, you can plug a trailer side 4-way trailer connector part # 002402 into a vehicle side 5-way connector part # HM37908 without any adapters needed.
    view full answer...
  • Towing a Trailer with a 4-Way Trailer Connector with a Vehicle that has a 5-Way Connector
    It sounds like you're trying to tow a trailer that has a 4-way connector, like part # HM38168, with a vehicle that has a 5-way connector, like part # HM37908. If this is the case you don't need any additional parts or a converter. A 4-way and 5-way will plug into each other you just won't have the 5th pin connected. Nor will you have the function that's carried on that pin. If this isn't what you're trying to do then let me know your exact set up so I can be more help.
    view full answer...
  • How to Add 5-Way Wiring Harness to a 2012 Ford Edge
    We do have some options for you to add a 5-Way wiring connector on your 2012 Ford Edge, but the available wiring kits that tee in behind the tail lights don't come with 5-Way connectors. Your options to adding a 5-Way include using a wiring kit like the T-One # 118515 and then cutting off the 4-Way and splicing in a 5-Way like the Hopkins # HM37908, OR you can just install a 5-Way harness that splices in completely like the Tekonsha # 119177. Attached are some videos you can check out...
    view full answer...
    Image 1 for
  • Shortest 5-Way Flat Vehicle and Trailer Side Connectors
    The shortest pre-made 5-Way flat vehicle side connector that we have is 48 inches long, # HM47900. If you need the trailer side instead we have # HM47910 or # HM37918 which are 18 inches long.
    view full answer...
  • Replacement 5-Way Flat Trailer Connector Recommendation
    The 25 Ft 5-Way Trailer Wiring Harness part # A25W5B will do the trick for you. It is a bit longer than you need but the 4 male and 1 female plug is usually found on the trailer and not the truck causing the long harness issue. Typically you find this on the the vehicle side of things. Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long part # HM37908 this would meet your requirements but you would have to change the trailer side to the harness listed above...
    view full answer...
  • What Type of Trailer Wiring Does Boat Trailer Typically Have
    Boat trailer 4-way trailer wiring is done in the same way as other 4-way trailer wiring. Sometimes boat trailer will use 5-ways instead if the trailer has surge brakes and the actuator has a reverse lockout which allows the trailer to back up without brake application. For that we have the part # HM37908 which comes with a 5 foot harness.
    view full answer...
  • Wiring 5-Flat Connectors on Jeep and Trailer
    It sounds like your trailer has a 4-flat wishbone connector, which will have 5 wires with two of them going to the tail light wires. If your trailer has brakes you will need to wire a 5-flat # HM37908 on your Jeep. For this harness, the white wire is the ground wire, the yellow is left turn/brake light, the green is right turn/brake light, the brown is tail lights and the blue is reverse lights. Your trailer will also need a 5-flat # A40W5B, which has a blue wire which disengages the surge...
    view full answer...
  • Recommended 5-Pole Flat Trailer Connector To Replace Damaged Connector
    If the 5-way connector you have is installed on the vehicle you can use part # HM37908. You would just cut the connector off of your vehicle and splice the # HM37908 with the length of wire you need. You can use butt connectors like part # DW05744-5 to connect the wiring. If the connector is on the trailer then you can replace the damaged connector with part # HM47910.
    view full answer...
  • Troubleshooting New Wiring Harness On Trailer For Reverse Lights
    In order to get the reverse lights to work on your trailer you will need a 5-way on your vehicle and also on your trailer. It sounds like you have wired the 4-way up but now you need the reverse lights. I recommend removing the 4-way connectors on both the towing vehicle and on your trailer and installing 5-way connectors. For the trailer side I recommend part # HM47913. You would attach the white, yellow(or light green), green, and brown wires to the same color on your trailer and then...
    view full answer...
  • Wiring for 2008 Toyota Tundra Towing Surge-Coupler Equipped Boat Trailer With 5 Pole Connector
    A brake controller like the Tekonsha # 90885 P2 is for use with electric brakes, not surge brakes like what your trailer is equipped with, so you wouldn't need a brake controller. A surge coupler will compress when the tow vehicle applies its brakes. This compression is what applies the hydraulic trailer brakes and is in effect, just like stepping on a brake pedal. The 5th wire on your trailer connector is for a reverse lockout solenoid which prevents the brakes from actuating when you...
    view full answer...
  • Adding 5-Way With 25 Feet of Wire to Back of Trailer For Lights on Cargo Carrier
    So I think we have a solution here for you, but there isn't a vehicle-end 5-way that has 25 feet of wire, so you'll need to splice in additional wire. As for using the blue wire, that is the reverse light wire on the 5-way, so you would need that since you want to utilize a reverse light. Here is what you would need: - Hopkins Wiring Harness with 5-Pole Flat Trailer Connector - Vehicle End - 5' Long # HM37908 - Primary Wire - 16-Gauge - White - per Foot # DW02359-1 - Deka Heat Shrink...
    view full answer...
  • 7-Way to 6-Pole Trailer Connector Adapter for Horse Trailers
    Most horse trailers have a 6-pole trailer connector. In order to attach the 6-pole trailer connector to your vehicle then you will want to use the Hopkins Heavy-Duty, Coiled Trailer Connector Adapter part # HM47083 if the center pin on your vehicle connector is for 12v power or part # HM47085 if the center pin on your vehicle connector is for the brake circuit. You will need a 7-way connector on your vehicle in order to activate the trailer brakes on your horse trailer. If you do not...
    view full answer...
  • Recommended 14 5-Way Flat Connector Harness With Protective Coating
    I may have an option for you but we do not sell a 14' 5-way flat connector harness that has a protective coating on it other than the wiring insulation. I recommend the 25' 5-Way Trailer Wiring Harness # A25W5B which can be cut down to 14' if you need the trailer side connector, or the longest vehicle side connector is the 5' Hopkins Wiring Harness with 5-Pole Flat Trailer Connector # HM37908 and adding Wire Loom # 7509-1 which is sold by the foot for further protection. It is also a...
    view full answer...
  • Trailer Connector for Towing Surge Coupler Equipped Trailer With 2013 Toyota Tundra
    I'll begin with the assumption that your new pontoon trailer has hydraulic surge brakes. This type of braking system uses a hydraulic coupler that compresses when the tow vehicle brakes, and the compression is what causes the brakes to actuate. A trailer like this usually uses a 5 pole flat trailer connector, with the extra circuit being the reverse lock out. The reverse lock utilizes a solenoid that prevents the brakes from applying with you attempt to back the trailer. Otherwise, especially...
    view full answer...

Do you have a question about this Trailer Wiring?

  • Why

    At we guarantee:
  • Highest quality trailer wiring for the best price.

    Our Lowest Price Pledge ensures you will never overpay for the parts you need.
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate trailer wiring information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Need to return an item? No problem. Please read our Returns Policy for more information.

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 Joshua S
Video by:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Cole B
Installed by:
Cole B
Employee Ryan G
Installed by:
Ryan G
Employee Alexander C
Written by:
Alexander C

At we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.