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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 800-298-8924 for expert service.
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Tow Ready Wiring - 30637

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

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   (62 Customer Reviews)

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

- 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 680193



- 30637
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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. 649776



- 30637
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great product , just what I needed at a good price 638554



- 30637
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Just what I need! Great product. Great video of product description really helped. 582883



- 30637
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GREAT PRODUCT AND THANKYOU FOR A SPEEDY DELIVERY, SUCH A NICE SURPRISE I LOVE YOUR SITE AND WILL DO MORE BUSINESS WITH YOU. THANKYOU SO MUCH. RONNIE. 580403



- 30637
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Durable / Easy Installation 568564



- 30637
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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. 567315



- 30637
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Have received but have not installed. Quality of product is very good. 442761


Comments
Works great
Doug W - 10/14/2018

44628

- 30637
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Fits perfectly on my 2017 Corolla 433340



- 30637
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Installed on Blu Ox tow bar yesterday. & plugged in to tow daddy wiring kit perfectly. 433328



- 30637
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Product has worked great, seems to be designed and manufactured very well. No issues at all. Would recommend to others. 431109



- 30637
by:

Correct product. Cheap delivery and I got it in two days. Super easy to assemble. etrailer is awesome, 423429



- 30637
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Excellent! After receipt of product, took less than 15 minutes to install on my truck & solved my problem. 403962



- 30637
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I've used this before, It gets the job done.... 400899



- 30637
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should do the trick 395692



- 30637
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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. 383408



- 30637
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Customer service at E trailer Is excellent I dealt with Lisa D she was extremely helpful and answered all my questions !!! 376043



- 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 371681


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

37686

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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. 368720



- 30637
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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. 348206



- 30637
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Great price real easy to order 345486



- 30637
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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! 340916


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

34697

- 30637
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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. 338059



- 30637
by:

Very good quality & arrived in a very timely manner. Hard adapter to find, 320499



- 30637
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Product was as described and received earlier than expected 317288


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Show More Reviews

Ask the Experts about this Tow Ready Wiring

  • 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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  • Recommended Trailer Hitch, 4-Way, and 6-Way Wiring for 2018 Toyota Sienna
    For your 2018 Toyota Sienna I do recommend installing a 4-Way harness and then going with a 4-Way to 6-Way adapter for when it's time to tow the pop-up camper. This will be the easiest and most reliable method for your vehicle. As you mentioned in your question your Sienna has a separate wiring system, which means the brake and turn signals are sent along separate wires. Because of this a powered converter is needed to not only safeguard the vehicle's wiring and provide enough power...
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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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  • 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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  • 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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  • Circuits and Functions Supported by 4-Pole Flat Trailer Wiring
    In 4-pole flat type trailer wiring such as part # 002220 the tail light circuit (also known as the running light circuit) is usually assigned to the brown wire which connects to the pin next to the ground pin. You can see this in the photo I linked for you. This type of wiring format does not support an additional circuit for +12V auxiliary power as might be needed to top off a trailer-mounted battery or to operate a jack or winch on the trailer. Other wiring formats with additional...
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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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  • After Replacing Trailer Side 4-Way Wishbone Harness with Non-Wishbone, Running Lights Don't Work
    The issue is likely in how the 2 brown wires are connected and then connected to the single brown from the new 4-Way. You basically need to make the 2 running light wires into one and then butt connect to the single brown. You could use the Quick Fix, # HMC20031, twist the two running light wires together and then put the newly combined wire in place. Or you could go ahead and swap the 4-Way for a wishbone, # A20WB. There also could have been a short that fried the lights when 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...
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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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  • Wiring Connections For Wishbone Harness To Use On Trailer Wiring
    It sounds like you have a wishbone harness. On a typical 4-way connector, you would have a yellow wire that would be for a left turn and left brake light signal, and a green wire for the right turn and right brake light signal. You would also have a single brown wire for the running lights and a white wire for the ground. A wishbone connector will have a brown/green wire for the running lights on the right side, and a yellow/brown wire for the left side running lights. you will also...
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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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  • What Parts Needed to Convert 4-Pole Connector on Tow Dolly to Match Motorhome Connector
    If your tow dolly uses a 4-pole trailer connector this means it has only stop/turn/tail lights, but not electric brakes. If your Class A motor home uses a connector like # 37995 you can simply wire in the trailer-side part of this item in place of your existing 4-pole. This will provide a more reliable long-term connection than an adapter. Adapters are definitely convenient, but the additional contacts they introduce can cause connection issues if corrosion or contaminants get in. Wiring...
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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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  • How to Identify Functions for Each Wire on a Trailer
    Trailer wiring often uses specific color wires for a particular lighting function but there is no guarantee that your trailer uses the common wire colors. This just means that you'll test the wires on the trailer to see what each one does; then you will know how to connect it. You can refer to the linked article on trailer wiring that shows the usual configurations of 4-pole, 5-pole, 6-pole and 7-way wiring. Photos are included to show you the usual wiring colors for each function. In...
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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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  • 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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  • 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,...
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    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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  • 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...
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  • Adapting a 6-Way Square Jayco Trailer Connector to 7-Way on Vehicle
    The easiest thing to do would be to replace the 6-Way square on the Jayco trailer with a 7-Way, # PK12706. You can adapt the 6-Way Jayco to the 7-Way on your vehicle. But it will take a little bit of work. First, you will need 6-Pole Square Trailer Wiring Connector Kit # 37995 because the Jayco square plug doesn't fit any other 6-Way square. This part has both the vehicle end and the trailer end which will both be needed. Then you will need a trailer side 7-Way such as # PK12706....
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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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  • 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...
  • 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...
  • 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...
  • 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...
    view full answer...
  • Replacement 5-Way Recommendation to Replace a 5-Way that Had 7-Wires Run to It
    What you have is a 5-way trailer connector with a wishbone running light circuit and 5th auxiliary circuit. The closest thing we have would be the Wishbone 5-way Part # A25W5B. This has a wishboned running light circuit, but the 5th circuit is not. You can still make this work though. You just need to run both of the red wires from your trailer wiring into one butt connector and then run the other side of the butt connector to the blue wire of the # A25WB.
    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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Info for this part was:

Expert Research:
Mike L
Expert Research:
Robert G
Expert Research:
Michael H
Expert Research:
Jeff D
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Jameson C
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Adam R
Expert Research:
Lori W
Expert Research:
Jeffrey L
Updated by:
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Updated by:
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