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Adapter 4 Pole to 6 Pole

Adapter 4 Pole to 6 Pole

Item # 30637
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Tow Ready Plug and Lead Wiring - 30637
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Tow Ready adapter converts your 4-pole wiring harness on your vehicle to 6-pole round connector. Lowest Prices for the best wiring from Tow Ready. Adapter 4 Pole to 6 Pole part number 30637 can be ordered online at etrailer.com or call 800-298-1624 for expert service.
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Tow Ready Wiring - 30637

  • Wiring Adapters
  • Single-Function Adapter
  • 6 Round
  • Plug and Lead
  • 4 Flat
  • Tow Ready

Tow Ready adapter converts your 4-pole wiring harness on your vehicle to 6-pole round connector.


Adapter converts your 4 pole wiring on vehicle to 6 pole round connector. Additional leads for brake (blue) and power (black) can be connected to allow for electric brakes and accessories.


Wiring Diagram



20320 Adapter 4 Pole to 6 Pole




California residents: click here


Video of Adapter 4 Pole to 6 Pole

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




Video Transcript for Tow Ready Wiring - Wiring Adapters - 30637 Review

Today we're going to review part number 30637. This is the Tow ready 4-Way Flat to 6-Way Round Pin Connector Adapter. Now, this adapter will convert your 4-pole wiring on your tow vehicle to a 6-hole round connector on your trailer. There are additional leads for the brake and for the power and also the white is for the ground. These can be connected to allow for electric brakes and accessories. Now, if you do have a, the 4-way right here would plug into the 4-way on your vehicle. Now, if the trailer has a 6-way and you just wanting to use the lighting functions, you can just plug in this 4-way and it would give you the lighting function.

You will still have to install this white wire with the eyelet to a big clean ground to get those functions to work. But, if you're wanting to use, I had an electric brake controller or any other 12-volt accessories, you do need to install these other 2 wires. Basically, what you would do is after you take the white wire and install it to a good clean ground, go to the blue wire. The blue wire is for the electric brakes. What you need to do, this would be routed under the vehicle using extra wire and then attach it to the blue wire on the brake controller. The black wire would be for 12-volt power.

This would have to be attached to a black wire and then routed under the vehicle and attached to the positive battery termining 00:01:24 with a 40-amp circuit breaker. Once you have that all hooked up, then you could plug in the 6-way on your trailer and get all the lighting operations, electric brakes, and still have 12-volt power. Length on this, to give you an idea of the measurement, lengthwise from the end of the 4-way to this about 15 inches in length. That should do it for the review on part number 30637. The Tow Ready 4-Way Flat to 6-Way Round Pin Connector Adapter. .


Customer Reviews

Adapter 4 Pole to 6 Pole - 30637

Average Customer Rating:  4.8 out of 5 stars   (63 Customer Reviews)

Tow Ready adapter converts your 4-pole wiring harness on your vehicle to 6-pole round connector.

- 30637
by:

I ordered SEVERAL products. As usual, they arrived in a timely manner, and well-packed. By ordering a Four-Flat to a Six-Round Adapter, I saved myself a lot of time trying to make one myself out of separate components. I needed this adapter to utilize my trailers on vehicles that Don't have Six-Round lighting connectors. This adapter is very well made, and functions perfectly! I also ordered some Four-Flat connectors so I can use rental trailers of a larger capacity or "Car haulers" that don't have Six-Round connections. ALL products purchased are excellent quality. Thank You E-Trailer!


Comments
All referenced products are still working perfectly. Thank You etrailer!
Sgt. L - 02/14/2018



- 30637
by:

I purchased this adapter to enable me to connect my vintage tent trailer. The wiring kit that came for my car had a four pin flat connector so that worked perfectly with this adapter. I just had to run the 12 low-power and I was good. The adapter appeared to be well constructed and everything so far tests out fine.



- 30637
by:

Very nice to deal with you folks. You site is carefully put together. Very clear formation and it was easy to make a choice. It was the correct part and did the job. I think you guys decided from the beginning to be the best at handling tedious problems with trailers and their saftey. Thanks for your good work


Comments
It was working great when I sold the trailer last Fall. Very good product
William C - 04/25/2018



- 30637
by:

I purchased this along with factory wiring connector for my Chevy K10- that was a breeze to click into the factory harness. I was having issues with the wiring job from before, i cam across Etrailer and found these quick install harness to fit my needs. it took less than 15 minutes to click in to space. i mentioned before, Cheaper than the local Trailer shop and no splicing. Good quality, on time delivery, easy to install.


Comments
GOOD NO PROBLEMS. EASY
Brad S - 09/06/2015



- 30637
by:

Perfect for my Dodge. I tore a rats nest out and did a nice clean installation. I ought the 4->6 pole adapter and spliced in the battery and brake lines to the provided butt splices. Very easy! Whole job took 45 minutes including getting the bleeding stopped where I banged my head on the frame rail of the truck.



- 30637
by:

First time purchaser. Very prompt service by following up via email, and quick shipping. Product came packaged very well and in excellent condition. I will be cataloging this website for future purchases. Have already recommended this business to friends.



- 30637
by:

This item will be used to connect the lights/brake between our motor home and 2016 GMC Sierra 1500. Received the item fast from etrailer. Would recommend etrailer to family and friends.


Comments
Made for an easy connection
Edward P - 05/06/2017



- 30637
by:

This product work perfectly. We just got a new camper and old one had 4 plug and the new one is 6 plug. This workout great.



- 30637
by:

The description online was very accurate and easy to purchase. The product we bought was exactly what we needed and received it in just a couple of days. I would diffinately recommend people to shop at etrailer.



- 30637
by:

I was so pleased with etrailer.com! My wife and I bought a camper and had no way to hook up the lights. Our product was delivered quickly so that I can go pick up our camper.



- 30637
by:

As a small business owner I am extremely pleased with the service and follow up that you provide. Making yourself available to your customers is very important. I also find the how to videos very helpful. I will highly recommend you to anyone who is in need of your products.



- 30637
by:

I was told to check out etrailer for all my needs anything for my trailer and like WOW!!!! They actually had what I needed and shipping was fast. It works perfect with NO issues at all. Thanks guys for your help on this and I will definitely order again from you.



- 30637
by:

Work perfect. This Adapter worked perfectly for what I needed. Seems to be heavy duty and durable. I'm using it for a Stock trailer to pull a horse. It was really helpful the way this site is set up. By having the customer tell them what type of plug from the Truck and Trailer, it advised me the exact plug I needed. No other auto supplier, Wal Mart or anyone I asked could get me the right plug.



- 30637
by:

I have several vehicles that required the installation of this adapter. I have had at lease two of them installed and in each instance these were quality items that fit perfectly and performed well.



- 30637
by:

I used this with a Ford Ranger adapter. It hooked right up. I didn't see that it didn't have the bracket to attach to my pickup. I bought one at an auto parts store. It was easy to attach and works. The price was the cheepest I found, shipping was great. Etrailer is great to work with. I will shop here again.



- 30637
by:

Installed on Blu Ox tow bar yesterday. & plugged in to tow daddy wiring kit perfectly.



- 30637
by:

Product worked as advertised. Did not utilize the brake wiring (didn't need to for my application). If I choose to keep permanently hooked on my 04 Pilot, will require some mounting hardware since tralier hitch doesn't really have anywhere to put it.



- 30637
by:

I had to give you this praise too! Great website! My son and I have both ordered recently! Fast, cheap shipping! Products worked AWESOME!!! Thanks! The wiring harness for his Dakota was awesome. The adaptor was even easier!



- 30637
by:

All of it was high quality and fairly priced. It's already installed, It would be nice to have a bracket option to mount the six pin socket to the hitch. I ran a hole on the passenger side flat metal bracket.



- 30637
by:

Only place I could find this hook up! Drove about $15 worth of gas going to the usual auto parts stores. No one had it. Came to etrailer, bang! Instant find (with help from a fella that put me right on the product number). Fast deal, fast shipping, exactly what I needed!



- 30637
by:

Have received but have not installed. Quality of product is very good.


Comments
Works great
Doug W - 10/14/2018



- 30637
by:

Very good quality & arrived in a very timely manner. Hard adapter to find,



- 30637
by:

Product serve it's intended purpose exactly as planned. Very pleased with the product and especially Etrailers service. Excellent communication.



- 30637
by:

Arrived quickly and was very well made . Works great. When I need something else for a trailer I will surely use their products. Thanks



- 30637
by:

Your site was the only one that showed the cable harness that I was looking for. Thanks and the shipping was fast.


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Show More Reviews

Ask the Experts about this Tow Ready Wiring

  • Wiring for Five Trailer Wires to 4-pin Connector on Tow Vehicle
    It would seem that your tow vehicle has a typical 4 wire connector where white is ground, green is the right turn signal, yellow is left turn signal and brown is running lights. In this configuration the brown wire from the car connects to the brown wire from the trailer. Also you tell us that your trailer has five wires which are connected to a flat 4-pole connector. It appears that you have a "Wishbone" configuration where two wires for the running lights are merged together for...
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  • Wire Colors for a Jet Ski Trailer
    It sounds like you are trying to determine which wire has winch function on your trailer. If that is the case then the color is more or less irreverent as the trailer manufacturer could have used any color they want for the respective signals. Therefore, the only true way to determine function is to apply 12 volt power to each wire and see which light it illuminates. I will however say that the white wire is usually a ground and the brown wire is usually for the running lights.
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  • Recommended 4-Way Trailer Wiring with 5 Wires
    For your 4 way Flat connector on your trailer, I recommend the Hopkins Endurance Quick-Fix Replacement 4-Way Flat Trailer Connector w LED Test Lights - Trailer End # HM48192. Your description talls me you have a wishbone wiring on your trailer which has two running light wires (one to each side of the trailer) so that a jump wire from one side to the other is not needed across your trailer frame. The two brown wires (running lights) will connect next to the white ground. Then you will...
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  • No Right Stop/Turn Lights On Small Box Utility Trailer With Running Lights On
    It looks like you have a standard 4-way trailer wiring harness therefore the white wire is indeed a ground, the brown wire is for the running lights, the green wire is for the right side stop/turn signal lights, and the yellow wire is for the left side stop/turn signal lights. If you are having issues with the right side stop/turn signal lights then first check to make sure there is not a fuse blown in the tow vehicle but if not then you need to start tracing the green wire all the way...
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  • Adapter to Connect 4-Way on Vehicle to 6-Way Round on Trailer
    A vehicle end wiring harness using a 4-Way Flat connector should have 3 female plugs and 1 male pin. A matching 4-Way Flat trailer connector would have 3 male pins and 1 female plug like on the Tow Ready Adapter 4-Way Flat to 6-Way Round, part # 30637. The # 30637 adapter is designed to plug into a 4-Way Flat on a vehicle and the 6-Way Round on the other end, with the male pins, will plug into a 6-Way Round on the trailer that has 6 female plugs. I am including a link to a FAQ page...
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  • What Adapter is Needed For Borrowed Trailer Pulled By Mercedes-Benz ML350
    It sounds like you have a 7-way connector on your ML350. If the trailer you plan on towing has the female version of your connector then you will not need an adapter. The other possible situation is you have the 7-way male connector on your ML350 and the trailer has a 4-way. If this is the case then Hopkins # HM47365 should work. In order to determine exactly what will work with the trailer, we will need to know what connector is used on the trailer. Not all trailer companies use the...
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  • Difficulty of Replacing Damaged Trailer Wiring
    Replacing vehicle- or trailer-side wiring is not difficult as long as you get the correct replacement part. It is often easiest to do this kind of job when you have a circuit tester like # 40376 to help you confirm what each vehicle wire does, and to have a 12V battery to test what each trailer wire does. Matching up the functions is important since trailer and vehicle wire colors are not standardized. If you'll need to splice wires you might want to consider a junction box like # 38656...
    view full answer...
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  • 4-Way Connector Needed to Replace 4-Way on Trailer with 6 Wires
    Since you have six wires it sounds to me like you have a double ground and a left and a right side tail light wire. If this is the case you could use a wishbone harness like the 20 ft. Wishbone 4-Way Trailer Wiring Harness with 30" Ground Wire, # A20WB, as a replacement because it has the separate left and right side tail light wires. I recommend using a spare car battery to assist with testing the trailer wires for function. You will just need to ground the negative terminal of the...
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  • Availability of a Replacement Jayco 6-Way Trailer Side Connector
    Jayco is the only manufacturer that uses that type of 6-Way connector. We do not have a replacement that is going to work. Since yours is broken this is the perfect time to install a 7-Way connector on the trailer so you do not have to mess with various adapters. If you do not want to change to a 7-Way on the trailer then you would need to get a replacement trailer side Jayco 6-Way from Jayco. But to add a 7-Way RV style connector to the trailer you can use something like # H20042. You...
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  • How to Connect a Jeep with 4-Way Flat Connector and a Winnebago with a 6-Way Round Connector
    If your Jeep has a 4-Way Round and your Winnebago has a 6-Way Round then you simply need an adapter like the Tow Ready # 30637. This comes with loose wires for a ground, 12V Power, and a Brake Controller which you may need for your trailer. Cut off your 4-Way Round and the 4-Way flat on this adapter and then splice the wires together function for function. This will pass along your basic lighting functions so if your trailer is equipped with brakes or need 12V Power then you will need to...
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  • 4-Way Trailer Connector that has 5 Wires
    Did you have a 4-pin connector that had 5 wires or was it a 5-pin connector? There is a big difference since you normally see a 5-pin connector on a boat trailer with the 5th pin used for an electric reverse lockout solenoid on a brake actuating coupler. If it was a 4-pin connector with 5 wires then it is called a wishbone harness and would have 2 wires attached to the running light pin so you have one wire for each side of the trailer. Typically, on a 4-Way, the white wire is ground,...
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  • Are 8 Side Marker Lights on a Trailer Too Much Power Draw
    The limit to the amount of lights you can connect to any given circuit on a trailer connector is up to several factors. Primarily it depends on what the vehicle side trailer wiring harness is rated for. If it is factory wiring then this information could be in the owners manual. If it is aftermarket then I would need to know the make and model of the harness and I might be able to determine what it is rated for. As long as the combined draw of all the lights on a given circuit are less...
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  • Replacing 5-Way Trailer Connector that Has 9 Wires Ran to It
    That's the most wires I've seen ran to a 5-way connector! Looks like you have several white ground wires, a running light circuit that runs to each side with the brown/green and brown/yellow, left and right stop/turn circuits, and then two reverse light circuits for the red wire. For the combined circuits like the red wires, white, etc. you can run them all to a single wire on your new 5-way connector like the part # HM47910.
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  • How to Determine Trailer Wiring Color Functions
    Since wire colors on trailer wiring aren't standardized you will need to test the wires on your trailer to determine their function before you can wire them to a trailer. An easy way to do this is to use a 12 volt battery and a jumper wire to apply voltage to each wire to see then what circuits activate. I attached a picture that shows a wiring diagram of a 7-way for you to check out as well.
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  • Why Does my 4-Way Connector Have 2 Wires Ran to One Prong for the Tail Light Circuit
    It sounds like you need an Optronics wishbone wiring harness, part # A35W42B. This 4-Way has a prong that has two wires that come out of it. The reason some 4-Ways have two wires coming out of one port is because that prong represents the tail light functions for both sides of the trailer. So one wire would run to the tail lights on one side of the trailer, and the other wire would run to the other. I attached a video below that shows this product being installed onto a trailer and...
    view full answer...
  • Replacing a 4-Way Connector on Trailer with 7 Wires
    From the information that you have given, I suspect that you have some additional ground wires on your trailer. Without being there to actually see the trailer, my best recommendation would be to wire the connector as follows: Green to Green for Right Turn Yellow to Yellow for Left Turn Yellow/Black and Green/Black to Brown for Running Lights White, White/Black, and Brownish White to White for Ground If the lighting on your trailer still isn't working as it should, I recommend...
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  • How to Tow a Trailer Designed for a Harley Streetbike with a Vehicle with a 4-Way
    We have what you would need to make the adapter you would need, but we don't sell one ready to go. What you will first need is the # PK12720 for your trailer to plug into, next you will need a signal converter to take the combined signal of your Jeep's 4-way to the separate signal of your trailer. For that you would want the # C56196. Lastly, you would need # HM48110 for a 4-way to plug into the Jeep 4-way. When connecting the converter to the 4-way the wires will match up color for...
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    Image 1 for
  • Left Turn Signal on Trailer Will Not Blink but All Other Lights Work
    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. 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 and corrosion free bare...
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  • Trailer Wiring Has 5-Wires White, Yellow, Green, Yellow/Brown, and Green/Brown
    On a 4-Way flat trailer wiring harness, white is the ground, brown is running lights, yellow is left turn signal and green is right turn signal. It sounds like your trailer has a wishbone harness. A wishbone harness splits the running light circuit at the connector so you do not have to run a jumper from one side of the trailer to the other side. On a wishbone 4-Way connector the white wire is ground, yellow is left turn signal, yellow/brown is left side running lights, green is right...
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  • No Running Lights On Trailer with Two Brown Wires (Wishbone Trailer Wiring Harness)
    The trailer you have utilizes a wishbone trailer wiring harness like the 35 Ft 4-Way Trailer Wiring Harness part # A35W42B in which the running light circuit is ran to each light on a separate wire from the trailer connector. The cause of your running and turn signals not working could be caused by several different things such as poor grounds, broken wires, incorrect routing, blown fuses etc. I would first start by checking that you have the wires routed to the correct circuits. The green/brown...
    view full answer...
  • Troubleshooting Pop-Up Camper Trailer Running Lights
    The additional electrical connection points created when a wiring adapter is used, something like # 30637 that connects a 4-pole flat to a 6-way round, can cause connection issues, but based on your testing and troubleshooting it sounds like your trailer running light issue is a weak ground on the trailer or on the vehicle. Often running lights reveal a problem with the trailer ground since these lights remain on. Brake and turn signal lights, which are typically on only briefly, draw...
    view full answer...
  • Why Does Haul Master 4-Way Trailer Wiring Harness have 5 Wires
    What you have is called a wishbone harness. The brown and red wires are both running light wires; one for each side of the trailer. This is so you won't have to run a jumper wire from one side of the trailer to the other in order to have running lights on both sides of the trailer.
    view full answer...
  • Wiring Replacement Trailer Side 5-Pole Wishbone Harness
    If your flat wishbone trailer connector has those 6 wires in total, then it is probably a 5-pole wishbone harness like # W002290 (since you also count the ground pin). The feature that makes it a wishbone type is the two dual-color running light wires, the yellow-brown and the green-brown wires, which both connect to the same pin for running lights. This pin is the one next to the ground pin as shown in the linked photo. The two wires merely simplify connection to the lights on the...
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  • 6 Prong Square on Jayco Trailer to 4 Prong Flat Wiring Color Scheme
    The wiring colors codes for the Jayco style 6-Way connector are not readily available. I can tell you that the following colors have worked out on a Jayco trailer before. Yellow - Not determined, Green - tail light, White - ground, Red - left turn and brake, Black - not determined and Brown -right turn and brake The leftover yellow and black wires would be used for auxillary power and backup lighting or trailer brake power, whichever is needed. You would need to use a circuit tester,...
    view full answer...
  • How Does Trailer Running Light Circuits with Yellow/Brown and Green/Brown Wires Run to New 4-Way
    The yellow/brown and green/brown wires are the running light circuit on the trailer. The new 4-way that has a single brown wire can still be used but you will need to run both wires of the trailer to single brown wire on the 4-way. This is a very common way to wire up a trailer and it will work great for you. If this configuration isn't working you will need to determine if the voltage is on the brown wire of your trailer when the running lights are on or not. If so, and still not working...
    view full answer...
  • Wiring Up a Harbor Freight 4-Way Trailer Connector and Trailer Lights
    Lets start with the trailer connector. I can tell you what the functions are so it will be easy to connect to the lights once we determine their functions. On a 4-Way, you will have one pin that is covered. That is the ground. Right next to it is the running light pin. Then the left turn/brake light pin. And the last pin is right turn and brake lights. Now, on the lights, since the common wire on both sides is red, I am inclined to believe this is the running light wire. What you...
    view full answer...
  • How To Hook Up Trailer with Two Brown Wires to Vehicle with One Brown Wire
    There should be five wires on your trailer side connector, a white wire which is for a ground, the yellow/brown and green/brown are for the running lights, a green wire for the right turn/stop light, and a yellow wire for the left turn/stop light because you have a wishbone wiring harness like part # A35W42B. In order to attach these wires to the vehicle side connector you will need to attach both yellow/brown and green/brown wires to the brown wire, the yellow wires together, and the green...
    view full answer...
  • 7-Way Blade to 4-Way Flat Adapter to Tow Boat Trailer with 2010 Chevy Silverado
    That is a standard RV style 7-Way trailer connector on the 2010 Chevy Silverado. For an adapter you can use # PK12716 to go to a 4-Way flat on your boat trailer. I have included a link to a video review of this adapter for you.
    view full answer...
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