Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector
(570 reviews)
Price: $35.66
Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector
Our Price: $35.66
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- All Info
- Reviews (570)
- Q & A (0)
- Videos (5)
- Photos
- Why etrailer?
Tow Ready Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 7 Round - Blade
- Plug and Lead
- 0 - 5 Feet Long
- 4 Flat
- Tow Ready
- Adapter converts from 4 pole wiring on vehicle to 7 pole round plug
- Additional wire leads for brake, power and accessory are 12" long
- Mounting bracket (18138) is sold separately
20321 Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector
Item # 30717
California residents: click here
Video of Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector
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 - 30717 Review
Customer Reviews
Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector - 30717
Average Customer Rating: 4.8 out of 5 stars (570 Customer Reviews)
- 30717
by: Bruce03/22/2022
i had to replace these two items as my dear daughter went down our goat path driveway too fast. they replaced the originals from etrailer from the prior year. shipping is timely and customer service actually helps! i wired from battery to controller to hitch myself, and everything fit.
- 30717
Sierra K - 12/01/2021
![Installation Instructions]()
Helpful Link
by: Bruce11/15/2021
Average quality part, would be nice to include a mount but ended up going the extra mile and used a hole saw to install it in my van’s bumper out of harms way. Would be easily damaged if mounted near the hitch.
Comments
Item # 18138
Mounting Bracket for 7-Way
$5.95 is the mounting bracket that works with this wiring.
-- Mounting Bracket for 7-Way
$5.95 is the mounting bracket that works with this wiring.
Sierra K - 12/01/2021
Helpful Link
- 30717
by: James H. Miller06/02/2017
This product works as expected. There is not too much to the installation, just plug it in properly and mount the ground wire. I did not find an easy way to mount this to my wife's Odyssey, or to the trailer hitch (item# 75270). Luckily, I do prototype design and manufacturing. So I came up with my own solution. I designed and made my own bracket to mount the 7 pole to the trailer hitch. It works like a charm, and looks great!
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by: Christopher01/13/2022
Installed the wiring harness for 2021 Toyota Tacoma. Everything went together just as noted in the instruction.
- 30717
by: roberto03/05/2013
this connector along with the short L bracket and the mount bracket- gave me a nice connector to my hitch. Though I used the short connector and did have to slightly bend it to allow the 4 to 7 pole connector to fit. If Id bought the long L bracket-- It could have worked-- but bending a little worked well.
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by: Chris03/21/2019
I was really skeptical about this adapter but for no reason! Installed in about 10 minutes using etrailer mounting bracket, dielectric grease, a couple zip ties, and some electric tape. Worked perfectly the first time I tested it on my trailer.
- 30717
by: James01/22/2022
Joe at etrailer was able to provide this solution and saved me literally hundreds of dollars to have a reputable place put in a new harness onto my AWD MKX. Thank you!
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by: Paul06/12/2021
I really appreciate you following up on my order. The information and videos will help when I drop the harness and circuit breaker off at my local shop. When I went to them originally with my problem I couldn't answer all their questions. With the parts in hand they should be able to convert my four prong to the seven prong plug used on my new trailer. Thanks also to Craig at CampInn for directing me to your site and the parts they are using in the construction of my trailer.
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by: Niv01/21/2022
Had a great experience ordering from etrailer. Product arrived fast and customer service was excellent.
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by: Gina12/02/2021
Yes, very nicely designed wiring harness. Works Great....
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by: Richard09/25/2021
Kyle was extremely helpful in not only finding the right hitch but the accessories I needed to go with it. Would definitely recommend etrailer.com to all my friends. Prices were excellent too!
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by: Marty Klemm06/24/2014
There was no splicing wires, it was plug-and-play, highly recommended, very easy installation
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by: Timothy10/04/2021
Worked as intended - wished they included a wiring diagram for us trailer newbies.
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by: Darrell08/12/2018
I wanted to show the custom installation. I did not want it under the bumper
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Laura E - 02/10/2017
by: Zach O02/03/2017
Works great. Easy install. It's more sensitive to dirt than I expected, but that might be common to all trailer connections, I don't know. I noticed on a trip that my brake controller said NC (no connection), and I didn't have trailer brakes, which meant my blinkers probably hadn't been working, either. I got pretty worried, and looked at it and only saw just a little black gunk on one blade. But cleaning that small amount of black gunk off solved the problem. So far, so good!
Comments
Thanks for your business and your review, Zach! Using dielectric grease like 11755 on your connections increases reliability and the life of the connection by preventing corrosion and sealing the connection.
-- Laura E - 02/10/2017
- 30717
Rics49 - 04/06/2015
by: Rics4903/17/2014
This is a great product . The price was $18.00 dollars cheaper than some I found online. I have a 2002 dodge ram 1500 pickup, this adapter will change the 4 pole( which is made on my truck) to a 7 pole( which is on the trailer I will be using). The product connected, and bolted up to my truck bumper very easy. E trailer is the best.
Comments
Im still enjoying this product, Ive used it several times, still workingwell
Rics49 - 04/06/2015
- 30717
by: Clinton03/13/2022
Install was really easy and seems to be holding up after 1 year well.
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by: Paul10/05/2021
Super Service at ETrailer - I have never had an issue with the help provided or with any product
- 30717
Al N - 05/26/2016
by: Al N.05/17/2015
I was surprised how fast the shipping was and the price for the product was very reasonable. I did not mind that there was no mounting plate for the adapter because I wanted something that would hook up to the camper when I need to use it and then take it off afterwards. I know I will be coming to etrailer for any other trailer or camper needs that may come up.
Comments
could not be happier with the purchase that I made
Al N - 05/26/2016
- 30717
by: kennth09/28/2020
Every time etrailer has provided me with the needed wiring!
- 30717
by: kurt k08/06/2013
Has been working great since purchased and installed 3 months ago. Used for several different trailers and long distance trips. Easy to install. Had to be slightly creative with the attachment of the ground. Did not see a reason to have a ground on this portion since everything else is already grounded, however would not work without grounding to the frame. Only used the four way connection and taped remaining three back. Hope for good things to come with this produce. Highly recommend this product.
Comments
Had the same issue with the ground kurt. Almost gave up on it until I read your post. Thanks.
-- comment by: mike g - 06/17/2014Comments
Thank you so much. Ours wasnt working either until we grounded it to car frame.
-- comment by: Sarah - 10/08/2015
- 30717
by: Cory B10/01/2013
This 7 point harness wired right in with my T1 connector and is great for hooking up to my camper, very easy to install!
- 30717
by: Richard S.05/25/2019
Used this adaptor to replace the factory tow package flat 4-pin connector on my 2019 Toyota Highlander. It's sad that Toyota is still using a cheap flat 4-pin connector on their factory tow package for a vehicle rated to tow 5,000 LBS. Would it really have cost that much extra for them to just use a round 6- or 7-pin connector to begin with? The installation was pretty straightforward using a new mounting bracket for the round 7-pin connector in place of the existing 4-pin bracket. I hooked up the white ground wire to the mounting screw for the new bracket after sanding paint off the bracket and nut and using dielectric grease for the ground wire and 4-pin connections. Spent some time re-routing and zip-tying wires and taped up the 3 wires on the adaptor that I won't be using. Nice clean installation. Trailer running lights, turn signals and brake lights work great. A quality product delivered in a timely manner by etrailer.com.
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by: Ronald03/27/2022
Works great!
- 30717
by: Reck008/28/2015
I was wanting to pull an enclosed trailer that has 7 pole plug in, with my vehicle that only has 4 pole plug in, without messing with the wires at this time, so I ordered the 4 pole to 7 pole adapter for this purpose. When item arrived I plugged adapter in, checked lights and on my way I went. all the extra wiring is there when I decide to add a brake controller. Now I can unplug the adapter and still use my 4 pole plug in. The item was well put together with tight wiring, price was reasonable, the shipping was smooth and the website is outstanding with plenty of instructions, wiring diagrams and the how to videos are a real plus on wiring up trailers. Thanks for an informative website and great product.
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Ask the Experts about this Tow Ready Trailer Wiring
- Where to Connect Blue Wire on 4-Pole to 7-Way Adapter Part # 30717 if Trailer Has No Electric BrakesIf the trailer you are planning on towing does not have electric brakes, you can simply leave the blue wire on the 4-pole to 7-way Adapter, part # 30717 disconnected. You can bundle it up, and zip tie it up out of the way. If the trailer does have electric brakes, a brake controller would be needed to actuate them. The blue wire would be extended and ran under the vehicle to the engine compartment, and through the firewall to connect with the blue brake output wire on the brake controller. To...
view full answer... - Can a Adapter 4 Pole to 7 Pole Be Used Just for Tail Light FunctionsYes, you could use this Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector # 30717 to adapt from a 4-way to a 7-way. You could simply tie they wires you would not use up and out of the way and you would be fine. You will still need to ground the white wire though. I attached an installation video for this product for you to check out also as well as an FAQ on trailer wiring for you to check out.
view full answer... - Trailer Lights are Not Working with 4-Way to 7-Way Adapter Plugged Into 2011 Ford EscapeFor the adapter # 30717 to function, the white wire has to be grounded to the vehicle frame. Without that ground it will not function. If it is properly grounded and you still do not have lights on the trailer, make sure that the adapter 7-Way and the trailer 7-Way pin configurations match up. I have included a link to our wiring FAQ article that shows diagrams of how various connectors should be pinned. If you are still not getting lights test the 4-Way on the vehicle with a circuit...
view full answer... - Dim and Malfunctioning Trailer Lights on a Trailer Towed by a 1988 Chevy C/K Series TruckThis sounds like a weak ground, corroded connector, or both. Make sure that the ground on the 7-Way you installed is attached to a clean and corrosion free bare metal surface. A weak ground could cause this issue. Ground problems normally show up when there is more load on the system like when the running lights are on and you step on the brake. Also make sure the 4-way that you installed is properly grounded. A corroded connector can cause all sorts of weird things to occur as well so...
view full answer... - Finding a Ground Location for a Trailer Wiring Harness on a Kia OptimaYou may need to scrape away some undercoating on the bottom of the vehicle in order to get a bare metal surface. Any surface with coating or paint will need to have those materials removed in order to get a good ground connection. Usually behind a tail light assembly there is some bare metal. You can also look for other wiring harnesses nearby and ground it in the same location.
view full answer... - Troubleshooting a 2006 Chevy Silverado 12 Volt Trailer Connector CircuitIt sounds like the 12 volt circuit has not been completed under the hood of your 2006 Chevy Silverado. Check out the FAQ article I attached that shows where this connection is made so that you can check there. You may find that the connection is made but the fuse is blown, so check and replace that as necessary.
view full answer... - Testing Wires On a 1994 Jeep Grand Cherokee to Determine Functions to Install a Trailer ConnectorYou cannot go by color because there is no standard for colors. You have to go by function only. To do this you will use a circuit tester like # 3808 and test the vehicle wires one at a time while someone sits in the vehicle and runs through all of the light functions. Then you can wire it all up following the functions (not colors) in the diagrams in the FAQ I have linked. On the trailer side, I assume the connector is fine. If the trailer is new then white is likely ground, brown is...
view full answer... - Troubleshooting Left Brake Light Not Functioning on a Trailer Towed by a 2002 Town and Country LXI would suspect you are having a ground issue. Ground issues usually come out when the brake lights are being applied because both tail lights are drawing the most amperage at that point. I would check your trailer connector for corrosion and clean as necessary-as the problem is usually there or where the tail light assembly grounds. If the tail light assembly grounds through the installation hardware you will want to be sure they are installed on a clean metal surface. I attached an...
view full answer... - Will Running the 12 volt Accessory Wire from a 7-way to a Trailer Battery Overcharge itThe battery charging method that you described would not overcharge the battery of your trailer at all. Actually, at most it will put a very light maintenance charge on the battery to keep it topped off, but would not recharge the battery if it was fully discharged.
view full answer... - How to Determine the Amperage on the 12 Volt Power Circuit in a Trailer ConnectorThe amperage on the 12 volt power circuit will depend on the amperage draw of the item receiving the power on the trailer. When aftermarket 7-way trailer connectors are installed on vehicles, it is recommended to have a 40-amp circuit breaker inline on the power wire going from the trailer connector to the battery. If your truck has factory trailer wiring, there will be a fuse in the fuse box designated for that circuit. You can check your owners manual to see the names and locations of...
view full answer... - Can the 7-Way Adapter part # 30717 be Used by Just Plugging in the 4-WayIf you do not need the additional functions beyond the trailer lighting functions that a 4-way carries you can use the part # 30717 by just plugging in the 4-way to it and you would be ready to go. You would want to tape up the additional wires up and out of the way.
view full answer...
- Troubleshooting Trailer Wiring that Stops Working When Headlights are Turned OnTry improving the connection of the main ground wire of the trailer wiring harness. Make sure it is attached to a clean metal surface. Or you can run all of the trailer wires back to the main ground. This is actually the ideal solution. But you can also check the current grounds for the lights to make sure they are making a solid connection to a clean metal surface. What you described is the classic insufficient ground scenario so finding a way to improve the grounds will fix the problem.
view full answer... - Troubleshooting Running Light Circuit on 2015 Ford F-150 4-Way Not WorkingCheck the fuses under the hood of your 2015 Ford F-150. Sounds like the trailer running light circuit has blown. Or if the running lights on the truck stopped working check the truck running light circuit as well.
view full answer... - Which Circuits on a Trailer 7-Way are for the Turn SignalsCheck out the diagram attached that shows what each of the circuits on a 7-way are. The right turn will be the pin in the 3:00 position and the left turn will be the 9:00 position. It sounds like these circuits aren't making a solid connection.
view full answer...
- Could Fifth Wire of Trailer 5-Way be Used for Brake Output for Brake ControllerIf you wanted to move the fifth circuit of your 5-way from being a reverse light circuit to a brake light circuit you certainly could. You would just need to remove it from the reverse light circuit and then wire it up to the front of the vehicle and attach it to the blue wire of your brake controller. Then the 5th circuit of your trailer's 5-way would need to get ran to the brake light.
view full answer...
- Where to Find Brake Output Circuit of 2006 Ford F-150 with 4-WayYou have to look at the driver side frame rail for the wiring needed to connect to the blue wire of the # 30717 that you have. I attached a couple pictures that show what you are looking for.
view full answer...
- How to Find Brake Switch Wire in a 1978 Ford F-100 for Brake Controller InstallationAre your vehicle brake lights still working when you press the brake pedal? If so, then it sounds like maybe you are testing the wrong circuit. It sounds like you could be installing a brake controller and are looking for the correct circuit to run to the stoplight circuit of the brake controller. If this is the case keep checking the circuits you found near the brake pedal till you find one that has 12 volts when the brakes are pressed and none when released. For more information on...
view full answer... - Wiring Adapter 4 Pole to 7 Pole Vehicle End Trailer ConnectorYou could wire the Tow Ready Adapter 4 Pole to 7 Pole # 30717 without the brake functions and just have the light functions on your tow vehicle without connecting the other wires. But I would be very cautious about not doing so for several reasons. The main reason is safety. The general rule for towing trailers with brakes is that if the Gross Trailer Weight is half of the Gross Vehicle Weight it is recommended to use a brake controller and have brakes on the trailer. Not being able to...
view full answer...
- Can Extra Wires of the 4-Way to 7-Way Adapter 30717 be Taped Up If Not NeededIf the surge brakes on your trailer do not have an electric reverse lockout then you could just tape up all of the wires that you didn't need of the # 30717 and you would be good to go. If the trailer does have an electric reverse lockout you would need to run the yellow wire to the reverse light circuit of your trailer and then also ground the white wire and you would be good to go.
view full answer... - Troubleshooting Trailer Lights That Flash with Blinkers and Don't work When Brakes are AppliedFirst thing I would do is check for corrosion in the 7-way of your 2004 Chevy Avalanche and clean as necessary. Most of the time this fixes situations like this. Aside from that the other most common problem is bad grounds on the trailer lights. You will want to make sure the grounds on the trailer light assemblies are connected to a clean metal surface. Also, the ground strap that runs from the trailer 4-way to the trailer frame needs to be connected to a clean metal surface. Aside from...
view full answer... - Can 4 to 7-Way Trailer Connector Adapter Be Grounded to Trailer Frame Instead of Vehicle FrameSince the 4 to 7-Way adapter # 30717 is a vehicle side connector it will be mounted on the vehicle. Grounding it to the trailer frame would mean you would have to disconnect that ground every time you disconnected the trailer from the tow vehicle. The trailer side connector already has a main ground connection so this one needs to stay grounded to the vehicle side.
view full answer... - Right Turn Signal Not Working on 7-Way After Installing 4 to 7-Way Adapter # 30717Since the brake lights and turn signals are combined on the same circuit, one for each side (3 oclock and 9 oclock pins) the right turn signal not working on the 7-Way is a little strange but not without precedent. It is likely a ground issue. Make sure that the white ground wire on adapter # 30717 is attached to a clean and corrosion free bare metal surface. Also, make sure the vehicle side 4-Way is clean and free of corrosion as well. Since the turn signal functions on the 4-Way it...
view full answer... - Recommended Wiring Connection Adapter for Jeep 4-Pin to Trailer 7-PinIf all you want to do is go from the 4-way trailer connector to the 7-way without adding functions, all you need to do is use an adapter like # 30717. You will simply plug in the 4-way and then connect the white ground wire with ring terminal to your vehicle frame. The ground needs a bare metal to metal connection free of debris and corrosion. The other three wires on the adapter can be left disconnected. The only thing to double check since you have a boat trailer is that you don't...
view full answer... - Does Blue and Yellow Wire of 7-Way to 4-Way Adapter # 30717 Need to be Wired InWhen installing the 4-way to 7-way adapter part # 30717 you only have to connect the circuits that you need. If your trailer does not have brakes and you don't need an auxiliary power source then those wires would not need to be connected to anything and could be taped up and out of the way.
view full answer...
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