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Adapter 4 Pole to 6 Pole

Adapter 4 Pole to 6 Pole

Item # 30637
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Trailer Wiring
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Adapter 4 Pole to 6 Pole 4 Flat 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 trailer 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 Trailer 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   (66 Customer Reviews)

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

- 30637
by:

Great product , no thinking on my part, just plug the wiring kit for my Honda CRV tow vehicle into this adapter.



- 30637
by:

Good material, good instructions, no problems with installation.



- 30637
by:

Everything works great



- 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 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:

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:

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:

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:

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:

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:

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:

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



- 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:

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:

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


Comments
Works great
Doug W - 10/14/2018



- 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:

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:

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



- 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:

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:

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



- 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:

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



- 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.


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Ask the Experts about this Tow Ready Trailer Wiring



  • Should Adapter 4 Pole to 6 Pole, # 30637 Have Constant 12 Volt Power Even With the Key Off
    I spoke with my contact at Tow Ready, and he stated that the Adapter 4 Pole to 6 Pole, # 30637, will have power at the 12 volt pin all the time if it is connected directly to the vehicle battery. This will not put a drain on the battery unless something is connected to the harness drawing power.
    view full answer...
  • Adapter 4 Pole to 6 Pole # 30637 Recommendation and Wiring
    It sounds like your trailer has a 6-way round connector and your truck has a 4-way flat connector. You could use an Adapter 4 Pole to 6 Pole, part # 30637, like what you referenced. If all you needed was tail light functions on your trailer you would simply mount the 6-way round of this adapter on your vehicle and secure the other wires up and out of the way, and then plug the 4-way from your truck into the 4-way of this adapter and then plug your trailer into the 6-way and you would be...
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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 will...
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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 have...
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  • Some Trailer Lights Are Not Working But Running Lights and Marker Lights Are Not
    You are probably on the right track in thinking a grounding issue is at fault. Often if a trailer has a weak or marginal ground connection it will be able to pass enough current for lower current draw lights (such as the turn signals that are not on continuously) but not enough for the always-on running and marker lights. I suggest you recheck the security of the ground connections. You can try sanding off paint (or rust) at the spot where your ground wire ring terminals are attached....
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  • Why Would 12 Volt Accessory Circuit of 7-Way Short Out While Towing
    You didn't say which fuse is burning up so it's hard to say. But most likely it's the 12 volt accessory circuit for the 7-way you have at the rear of your truck. Either the circuit is getting overloaded by the accessories you have wired to this circuit on your trailer or there is a short somewhere on this circuit that is causing the fuse to blow. Check the circuit for cut or exposed wire and fix as necessary as that is most likely the problem. Another possibility is that corrosion on the...
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  • 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...
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  • Installation Of Trailer Lights And Wiring On Utility Trailer
    When you are installing a 2-wire light on your trailer and they have a red and a black wire, the black wire will be for the running lights, and the red wire will be for the brake and turn signal function. It sounds like the lights are grounded through the mounting hardware on the trailer frame. I have attached a helpful article that explains how trailer wiring should be run. I have also attached a drawing that shows how wiring is typically run on a trailer you can check out.
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    Image 1 for
  • Front Clearance/Side Marker Lights Don't Work But All Other Trailer Lights Do Work
    The rusted ground location could create a weak ground so that some of the lights (usually the ones closest) could still work but others may not so it is worth cleaning away any corrosion. On the wire you mentioned that was exposed that you then taped corrosion could have gotten in and/or there could be other unseen damage. If you were to disconnect some of the lights attached to the running light circuit and that causes those front clearance/running lights to start working then the issue...
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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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  • 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 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 providing...
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  • Replacing 4-Pole Trailer Connector on Trailer With 7 Different Circuits Feeding It
    It sounds like you've got a pretty good handle on what you're dealing with. You're correct, the green is right turn/brake, yellow is left turn/brake, black/green is right taillight and black/yellow is left taillight. The remaining wires are almost certainly grounds. I'm guessing you're not the original owner of the trailer or the person who wired it last time. Rather than grounding each trailer lamp directly to the trailer frame by its mounting studs or individual ground wires connected...
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  • How to Install a Wishbone Wired 4-Way to a Trailers Wiring
    To wire the 4-way connector you have to your trailer you will need to ground the white wire, run either brown wire to the left or right side running light circuits, run the yellow wire to the left stop/turn circuit, and the green/brown wire to the right stop turn circuit. It could be that your trailer's wiring needs to be cleaned up a bit. You will want to check and make sure all of the wire colors I mentioned only activate the circuits I said they correspond to. If not, then there might...
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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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  • Trailer Has 2 Wires for Running Lights but Only One Running Light Pin on Trailer Connector
    It sounds like you might have a wishbone type of wiring situation. This means that the running light circuit is split to 2 wires instead of just one for running lights on both sides of the trailer (yellow of left side, green for right side). This is so you do not have to run a jumper wire for running lights from one side of the trailer to the other. You should just have to connect the 2 running light wires together and then connect them both to the running light pin or wire. If you have...
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  • Trailer Connector is a 4-Way Flat but has 5 Wires
    On the vehicle side connector, white is ground, brown is running lights, yellow is left turn/brake lights and green is right turn/brake lights. On the trailer side, since the black is the ground we can move on to the other wires. You likely have 2 running light wires, one for each side of the trailer. This is done so you don't have to splice in a jumper wire from one side of the trailer to the other. So the yellow wire is likely the left turn and brake light, green is likely right turn...
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    I am a little confused as to were the connector is, on the truck or on the trailer. Brown wires are typically associated with running lights. If there are 2 wires coming out of that pin and we are talking about the trailer side then you have what is called a wishbone harness. It will still function exactly the same as a regular 4-wire 4-Way connector. It just has 2 running light wires to run to the 2 sides of the trailer to limit the amount of splicing you have to do. If we are talking...
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    Is this the trailer side connector? It is likely that you have white for ground, yellow for left turn and brake lights, green for right turn and brake lights, and the 2 brown wires are running light circuits, one for the left side (yellow/brown) and one for the right side (green/brown). I imagine that you have a 4-Way flat connector. On the trailer side the one covered pin is the ground, next to it is the running light circuit, then left turn/brake, and last is right turn and brakes. If...
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  • 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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  • 4-Pole to 6-Pole Adapter for 2008 Toyota Tacoma
    Hello! Yes, the 4-Pole to 6-Pole Adapter # 30637 is exactly what you need to convert the 4-way on your 2008 Toyota Tacoma to a 6-pin.
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  • Installing 4-Way Flat Connector on Trailer with 3 Wires
    If your trailer is wired for both brake/turn signals and running lights, I'm wondering if the two multi-color wires you found (the green/brown and yellow/brown) are actually each 2 wires sealed together and they simply need to be pulled apart. If this is the case, then you actually have what is called a wishbone harness on your trailer, which uses a separate brown running light wire for each side of the trailer, along with the green wire for right side turn/brake and the yellow wire for...
    view full answer...
  • 4-Way Trailer Wiring Harness has 5 Wires Coming Out of It on 2001 Pontiac Aztek
    It would be very unusual for your vehicle to have a 5 way pin connector at the rear of your Aztec. It sounds like you have a wishbone harness. A wishbone harness has 5 wires and 4 pins like a regular 4-Way but where the wires come out the running light circuit is split so you do not have to run a jumper wire between tail lights. The wishbone harness will work with your trailer's 4 way connector.
    view full answer...
  • Troubleshooting Trailer Wiring That Right Turn/Brake Stops Working When Headlights are On
    You have a weak ground on the taillight assembly on the right side of your trailer. Make sure that the trailer side connector 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 metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding...
    view full answer...


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