7-Way connector is designed for use on vehicles with Trailer Lamp-Out sensors - Audi, Mercedes-Benz, and Volkswagen vehicles with the factory tow package - when towing a trailer equipped with LED lights. Call 800-298-8924 to order Curt custom fit vehicle wiring part number C57003 or order online at etrailer.com. Free expert support on all Curt products. Guaranteed Lowest Price and Fastest Shipping for 7-Way Trailer Adapter for VW, Audi, and Porsche Towing Trailers with LED Lights. Custom Fit Vehicle Wiring reviews from real customers.
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7-Way Trailer Adapter for VW, Audi, and Porsche Towing Trailers with LED Lights

Item # C57003

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  • Custom Fit
  • Trailer Hitch Wiring
  • Curt
  • 7 Blade

Curt Custom Fit Vehicle Wiring - C57003

7-Way connector is designed for use on vehicles with Trailer Lamp-Out sensors - Audi, Mercedes-Benz, and Volkswagen vehicles with the factory tow package - when towing a trailer equipped with LED lights.


  • Plugs into an existing 7-way socket to provide a new 7-way socket that is able to recognize LED trailer lights
  • Designed for use on vehicles with Trailer Lamp-Out sensors - such as Audi, Mercedes-Benz, and Volkswagen vehicles with the factory tow package
  • 1-Year limited warranty

57003 Curt 7 Way LED Trailer Light Adapter

This Product Fits The Following Vehicles

2011 - 2012 Porsche Cayenne

2007 - 2012 Audi Q7

2007 - 2012 Volkswagen Touareg

2008 - 2010 Porsche Cayenne excluding with Rear Mounted Spare

2008 - 2012 Porsche Cayenne with factory 7-Way

2007 - 2012 Audi Q7 with factory 7-Way

2007 - 2012 Volkswagen Touareg with factory 7-Way

Video of 7-Way Trailer Adapter for VW, Audi, and Porsche Towing Trailers with LED Lights

Videos are provided As a guide only. Refer To manufacturer
installation instructions And specs For complete information.

Video Transcript for Curt Wiring C57003 Review

Today we're going to review part number C57003. This is the Curt 7-Way to 7-Way LED Trailer Light Adapter for Audi, Porsche and Volkswagen. This is a custom fit adapter, this is designed to fit the 2007 to 2012 Audi Quattro, the 2004 to 2012 Porsche Cayenne and the 2004 to 2012 Volkswagen Touareg. Basically what this does is right here we'll plug into your existing 7-way on your vehicle. Then it provides this new 7-way that will work with LED trailer lights. If you plug in your trailer and it has LED lights, this will actually contain, right in here they do put resisters, load resisters.

What that will do is simulate the increased power draw so the vehicle thinks there is incandescent lights on the trailer. Then you won't get the lamp bulb out reading that usually flashes on the dash of those vehicles. There is no splicing required, just a plug in piece. That should do it for the review on part number C57003. The Curt 7-way to 7-way LED trailer light adapter for Audi, Porsche and Volkswagen. .

Customer Reviews

7-Way Trailer Adapter for VW, Audi, and Porsche Towing Trailers with LED Lights - C57003

Average Customer Rating:  4.5 out of 5 stars   (19 Customer Reviews)

7-Way connector is designed for use on vehicles with Trailer Lamp-Out sensors - Audi, Mercedes-Benz, and Volkswagen vehicles with the factory tow package - when towing a trailer equipped with LED lights.
- C57003

by: Ed05/28/2016

my problem: '11 ML350. trailer LED running lights would only flash (like emergency flashers). All other functions worked find - turn signals, brakes, etc. There were no warning lights/codes, etc displayed on the dash. This product completely solves this problem - it's a quality built product at a reasonable price. Although the trailer end of the pigtail includes mounting bracket for a permanent installation, I won't go to that extent as I rarely use the trailer. I will most likely just zip tie the pigtail to what ever is convenient to eliminate any flopping around while on the road. 252569


1 yr later - still working great wno issues whatsoever.

Ed - 05/28/2017

- C57003

by: Richar F.09/03/2014

Item worked great. After 3 1/2 years of the dealer trying to figure it out, this did the trick. Back up circuit on the factory wiring for the trailer did not work, although all the other circuits did, even with LEDs on the trailer. Now all of it works. If I could just get rid of the error messages looking for trailer directionals and running lights. I am just using the plug for auxillary back up lights which now work nicely. Adapter is used on Mercedes GL 350. 149898

- C57003

by: Lauren04/20/2016

Great service! I had to change the delivery address and it was done with no problem. I was stranded at a relatively remote location and UPS delivered the next day so I was able to get on the road. The original adaptor shorted out after 3 months and an autopsy showed the reason. The new unit had no such defect and I expect many years of good service from it. 246308

- C57003

by: eTrailer in the Know06/21/2013

Ford's better idea caught up with them on my 2013 Escape. computer notified "trailer light fault" with each brake application & turn signal not hot to mention the fast blink of the turn signal. Etrailer tech knew of fix for European autos and trailers with LED lighting. Works like a Champ and an Easy Install. 85475

- C57003

by: Todd G.08/09/2015

I cannot rate this product (but I am forced to enter something so I rated it in the middle) as it did not resolve the problem I am having. The etrailer team did an outstanding job getting the product delivered to me before we left the campground we were staying at. 217905

- C57003

by: Tim04/01/2015

Worked perfect on my 2005 Cayenne S. Trailer lights are blinking dimly and only brake light works without this. No parking lights nor signal lights work too. I'm going to let everyone on Porsche Cayenne knows about this product. 182127

- C57003

by: gtannboy10/05/2016

The low voltage on the trailer LED lights did not work with the MB GL350. This part corrected this problem and has performed perfectly. Completely satisfied. 303439

- C57003

by: John Dzerdz10/17/2014

Unfortunately this product did not stop the problem I'm having with my LED trailer lights. Possibly I ordered the wrong item. 156597

- C57003

by: Janis levesque07/27/2013

Not sure yet...this doesn't look like an "adapter" and I already have all original connections in place...so we will see... 91960

- C57003

by: Mrltml08/31/2015

My 2014 Ford Escape BLS and trailer connection sensor charmed constantly. This turned out to be the remedy. 223149

- C57003

by: Nick D11/08/2016

Worked perfectly on my 2016 Tesla model X w/ my brand-new gator-made trailer using LED lights. 314778

- C57003

by: Richard S.11/12/2014

Solved all my lite problems. Good service, quick shipping. No complaints. 160583

- C57003

by: Alan07/25/2015

MB 2008 ML320 - LED problem solved GREAT SERVICE needed in two days got it 214344

- C57003

by: Paul C07/06/2016

Works as advertized. Robust and waterproof after a year's use. 268777

- C57003

by: Oscar04/15/2017

Reliable product no problem behind used on a VW TOUAREG TDI 367710

- C57003

by: Dean m06/05/2016

Fixed my issue! Great inexpensive resolution - thank you! 257727

- C57003

by: Charley07/17/2016

Looks good. Did not try using it yet. Well made product 272933

- C57003

by: Jay McBain06/24/2016

After one year, wiring still works like new! 264785

- C57003

by: Sam E.10/22/2014

Simply did not work with my LR3 157463


Ask the Experts about this Curt Custom Fit Vehicle Wiring
Do you have a question about this Custom Fit Vehicle Wiring?

  • Using an Adapter to Tow a Trailer with LED Lights with a 2012 Mercedes GL450
  • Yes. If your trailer with LED lights has a 5-Way or 4-Way flat connector then you would use adapter # TR20141. If the trailer has a 7-Way connector you would need # C57003. These adapters have load resistors in them that provide additional power draw so the vehicle thinks there are incandescent lights on the trailer. The other option is to install load resistors, # P230004A, in line on each circuit on the trailer wiring behind its connector. You can also use this method if the resistors...
    view full answer...

  • Trailer Lights Do Not Work with 2014 Chevy Silverado But Do Work with 2008 Chevy Silverado
  • The trailer connector on the 2014 Chevy Silverado will be the same as previous generations because it is an industry standard. Factory integrated trailer brake controllers sometimes will not work with electric over hydraulic braking systems so if that is what is on the trailer then that could be the problem. The solution would be to install an aftermarket brake controller that is compatible with electric over hydraulic brakes like the P2, # 90885, using wiring harness # 3016. But since...
    view full answer...

  • Adapter for 2010 Mercedes-Benz GL450 Towing Trailer With LED Lighting to Avoid False Short Indicator
  • The answer is that you are needing the TowReady # TR20141. This adapter is used because LED's draw such low power that a lot of times on German vehicles your lamp out indicator will illuminate giving you the impression that you have an issue, when in reality you do not. With this adapter you will be able to tow your trailer with your 2010 MB GL450 without a problem. The adapter has built in load resistors that create more draw so the sensors think everything is working normally. If...
    view full answer...

  • Trouble Pairing the Tekonsha RF Trailer Brake Controller with an Audi Q7
  • Pairing problems are not uncommon with any wireless device and the Prodigy RF, # 90250, is no exception. At various points in the installation procedure the instructions will tell you that you should see something specific on the display. However sometimes the specific display does not show up. This is where most people stop and start all over. What you should do is keep going on to the next step. My contacts at Tekonsha have stated that for some reason what the instructions say should...
    view full answer...

  • LED Lights Flash on Trailer Towed by a 2008 Land Rover LR3 Using Adapter # C57003
  • The 7-Way to 7-Way adapter, # C57003, is designed to work on German vehicles like the VWs, Audis, and so on to deal with a bulb-out sensor issue present on those vehicles. It may not work the same for other applications like on your Land Rover. If the LED lights on the trailer are not providing enough power draw on the system you can try installing some load resistors on each of the lighting circuits (right turn/brake lights, left turn/brake lights) behind the trailer connector. You...
    view full answer...

  • LED Trailer Lights Not Working with 2016 Tesla Model X with Tow Package
  • The issue your are experiencing is likely similar to the problems that require adapter # C57003. The LED lights do not draw enough power for the tow package to recognize that they are there. The brake magnets draw more power which is why the controller recognizes that a trailer is connected. The load resistors in the adapter will simulate increased load on the system allowing the LED trailer lights to work. LED lights do not draw much power but the range on your 2016 Telsa Model X is...
    view full answer...

  • Tips for Getting a Prodigy RF Brake Controller to Pair on German Vehicle
  • The issue you are having is not uncommon for German vehicles. There are a few things you can try to get the unit to pair. First, If you do not see displayed what the instructions say just keep going through the steps. Sometimes, it will not display what it is supposed to but it will still work if you go through the steps to completion. If that does not work then you can try taping off the pin in the 5 oclock position at the back of the RF (where the trailer plugs into) using electrical...
    view full answer...

  • Check Trailer Wiring Message on a 2014 Chevrolet Silverado 2500 Duramax
  • There could actually be a problem with the trailer wiring and your 2014 Chevy Silverado 2500 is sensing it. Make sure the vehicle and trailer side connectors are clean and free of corrosion inside where the wires attach and outside on the pins. The ground wire on the trailer should be attached to a clean and corrosion free bare metal surface. Inspect the trailer wiring and fix any damaged or pinched wires. If the trailer has LED lights that could be the issue since LED lights draw...
    view full answer...

  • LED Trailer Tail Lights Will Not Work when Connected to a 2009 Mercedes GL550 with Factory 7-Way
  • There is an issue with German vehicles (Audi, Mercedes, Porsche, BMW, Volkswagen, and so on) and trailers with LED lights. The LED trailer lights do not offer enough draw on the system for the lights to work. On a lot of these vehicles you will also get a bulb-out warning in the vehicle. The solution is to use an adapter that has load resistors in it, # TR20141, to provide enough draw so the lights will work and so you will not get that bulb-out warning. The adapter will go from a 7-Way...
    view full answer...

  • Is a Special Converter or Adapter Needed to Tow a Trailer with LED Lights
  • Most aftermarket trailer wiring harnesses are compatible with LED trailer lights but I would need to know the year, make, and model of the vehicle to be sure. Factory tow package wiring usually works fine but German vehicles (Volkswagen, BMW, Audi, Mercedes) can have issues since the LED lights draw far less power than incandescent lights. I have heard of only a few cases of other vehicle manufacturer tow package wiring being an issue with LED lights. But even if the low power draw causes...
    view full answer...

  • Will 7-Way to 7-Way LED Trailer Light Adapter for German Vehicles Fit a 2014 Volkswagen Touareg
  • Yes, you can use the Curt 7-Way to 7-Way adapter # C57003 with your 2014 Volkswagen Touareg. It can actually be used with any vehicle that has a 7-Way. The vehicles listed were the ones that this adapter was originally created for because that is when the issue with LED lights and bulb-out sensors became apparent.
    view full answer...

  • Turn Signal Hyperflash on Tow Vehicle Towing a Boat Trailer
  • It sounds like you have experienced a hyperflash condition. LED lights will flash like that because they do not provide enough power draw for the system to recognize them. Also, you should not mix LED and incandescent lights on a trailer. If the vehicle has LED lights and the trailer has incandescent lights then as long as the vehicle has the proper converter installed or has the factory wiring harness it should be fine unless it is the factory harness on a German vehicle like a BMW...
    view full answer...

  • Trouble Pairing the Prodigy RF with Remote on a 2017 Volvo XC90
  • Your odds are better than average! Pairing the hand held remote with the Prodigy RF # 90250 can be tricky sometimes. We have compiled a list of possible remedies though that you can try to get the unit working. First, If you do not see displayed what the instructions say just keep going through the steps. Sometimes, it will not display what it is supposed to but it will still work if you go through the steps to completion. If that does not work then you can try taping off the pin...
    view full answer...

  • LED Light Bar and Hitch Light Cause Error Warnings and Disable Backup Features on 2015 Ford F-150
  • The issue might be that the LED lights do not draw enough power and it is confusing the computer on your 2015 Ford F-150. If you accessories plug into a 4-Way then you could use adapter # TR20141 which has built in load resistors to add more load to the system so it won't confuse the computer. If they plug into a 7-Way we have a similar adapter, # C57003. There may be other ways to disable those alerts or to have manual control over them but you may need to check with a Ford technician...
    view full answer...

  • Replacement 7-Way Trailer Socket for Factory Connector on 2008 Toyota 4Runner
  • We do offer a replacement 7-way/4-pole trailer socket to replace the factory-installed part on your 2008 Toyota 4Runner. Hopkins offers their Connector with Mounting Bracket Kit, part # HM43374, which is a direct factory replacement. This socket installs using the two included connectors which match those on the vehicle. The linked photo illustrates those two connectors on the replacement 7-way.
    view full answer...

  • Trouble Pairing the Prodigy RF with a 2014 BMW X5
  • The issue you are having is not uncommon for German vehicles. There are a few things you can try to get the unit to pair. First, If you do not see displayed what the instructions say just keep going through the steps. Sometimes, it will not display what it is supposed to but it will still work if you go through the steps to completion. If that does not work then you can try taping off the pin in the 5 oclock position at the back of the RF (where the trailer plugs into) using electrical...
    view full answer...

  • Trailer LED Tail/Clearance Lights Illuminate at a Low Level Even When Tow Vehicle is Not Running
  • It is not unusual for extremely-efficient LED trailer lights to show residual low-level illumination when installed in lighting circuits that originally had incandescent lights. These circuits typically always carry some small amount of power even when the tow vehicle is off. With low-efficiency incandescent type lighting this low power will not be evident as it is not enough to cause those bulbs to light up, but with super-efficient LED lights it can be enough to make them illuminate. The...
    view full answer...

  • Is Curt Adapter C57003 for Use Only with LED Trailer Lights
  • Curt 7-Way-to-7-Way wiring adapter # C57003 is intended for specific applications with import vehicles like Mercedes, Audi and VW when they tow a trailer that has LED lights. The vehicles that require this adapter are those that have bulb-out sensors which can be fooled by the low power draw of LED trailer lights. Such low power draw can cause the vehicle to think you have a bad bulb and cause an error message on the instrument panel. This adapter has a male plug that connects to a vehicle...
    view full answer...

  • Will Tow Ready 7 to 5-way Adapter for German Cars and LED Trailers Support Reverse Light Circuit
  • If you used the Tow Ready 7-Way to 5 or 4-way # TR20141 that you referenced with a trailer that has a 5-way then yes, the reverse light circuit will be active. If you used it with a 4-way then no it would not. That fifth circuit is for reverse lights. There would be no noticeable load or drain on the vehicles electrical system from the wiring of this adapter either. If you needed just a 7-way adapter that will work on the German cars that are sensitive to the LED trailer lights you...
    view full answer...

  • Troubleshooting LED Utility Trailer Lighting on a 2011 Mercedes-Benz GL450
  • Good news, you are correct in that the Tow Ready # TR20141 adapter will fix your 2011 Mercedes-Benz GL450 to work with your LED trailer lights. Some makes of cars are more sensitive to the LEDs and this adapter contains a resister that's needed to accommodate that sensitivity. With the # TR20141 adapter it will end up taking you from a 7-way to a 4-way, but if your trailer is a 7-way plug I'd recommend the # C57003. The Curt adapter has the same resister but allows you to still have...
    view full answer...

  • Trailer Brakes Pulse with Turn Signal Using the Prodigy RF Brake Controller on a 2011 BMW X5
  • That is not normal operation for the Prodigy RF brake controller # 90250. The likely issue is the sensitive nature of the tow package wiring on the 2011 BMX X5. But what you can use is use adapter # C57003 which will maintain more load on the electrical system so that all of the signals running through the RF have a high enough voltage/amperage for it to work properly. In the mean time I recommend using the manual override on the in-cab controller part of the RF to apply constant voltage...
    view full answer...

  • Trailer LED Lights Not Working when Connected to a 2012 Mercedes ML350
  • This is a common problem with Mercedes vehicles and trailers that have LED lights. Basically the LED lights do not draw enough power for the vehicle to recognize they are there and sometimes they sense it as a burned out bulb so you might see an error message displayed in the vehicle. One option is to use a special adapter, # TR20141 for a 7- to 4-Way or # C57003 for a 7- to 7-Way. These adapters have load resistors to simulate incandescent bulbs so the LED lights will work. If the...
    view full answer...

  • Wiring Adapter for Land Rover to Allow Proper Operation of LED Trailer Lights
  • We do offer wiring adapters for import vehicles to help them properly operate the LED lights on a trailer. If both the vehicle and trailer have a 7-way RV style connector then you can use part # C57003 from Curt. If the trailer has a 4-pole flat connector then instead you'll use # TR20141 which provides that connection. Both of these require a 7-way socket on the vehicle, like the one shown in the linked photo.
    view full answer...

  • Length of the Wire on the Curt 7-Way Adapter part # C57003
  • I pulled a Curt 7-Way Adapter par # C57003 from our warehouse to measure it and found that the wire measures 9-1/2 inches from the back of the mounting surface to the end of the plug. Check out the video I attached to see this measurement.
    view full answer...

  • Can Factory Trailer Wiring Harness on 2015 Porsche Macan Deliver 40-Amps Current for Chair Lift
  • Since we do not sell the OEM wiring harness that was factory installed in your 2015 Porsche Macan you can determine its amperage capacity by checking with your dealership or by seeing what value fuse is associated with it. It is NOT likely that the wiring harness can deliver 40-amps especially if the vehicle uses low-power-demand LED lighting. You'll also want to confirm the actual power draw from the lift's motor; is the 40-amps continuous or peak current draw? Tri-Lift offers several...
    view full answer...

  • How to Fix Check Trailer Wiring Message on 2015 Chevrolet Silverado and Trailer with LED Lights
  • The Curt 7-Way Trailer Adapter # C57003 is designed to be used on Volkswagens, Audis, and Porsches but we have seen some success on other vehicle makes. I can't say for sure but it might solve your issue. The adapter uses load resistors which creates more power draw. Another possible solution is to install load resistors # P230004A-2.
    view full answer...

  • 7-Way RV-Style Wiring Extension for 2006 Toyota 4Runner
  • The Curt 7-Way Trailer Adapter # C57003 is meant specifically for German auto brands that use light-gauge wiring and LED lighting. This is not recommended for your 4Runner for this reason. If you need a 7-way RV-style wiring extension you can make up one yourself using parts # 50-87-002 (2-feet long) and # A7WCB along with butt connectors like # 05731-5. Or you can simply order part # TLW6021, which is 2-feet long.
    view full answer...

  • Trailer Wiring Kits for 2009 Volkswagen Touareg TDI
  • The Curt 7-Way Wiring Adapter # C57003 is a special type of adapter that is used when certain import vehicles like VWs tow a trailer that has LED type lighting. LED lights use very little power so they can sometimes have compatibility issue with vehicle wiring that is expecting to see the much higher power draw from standard incandescent-type bulbs. This adapter does plug into a 7-way and in turn provides a new 7-way socket for a trailer's plug. This connector format carries lighting, trailer...
    view full answer...

  • LED Lights on Trailer will not Work When Towed with 2008 Mercedes-Benz ML320CDi
  • An adapter like the 7-Way to 7-Way LED Trailer Light Adapter, # C57003, contains load resistors which simulate increased power draw so the vehicle thinks there are incandescent lights on the trailer. Just plug this adapter into the back of your Mercedes, plug the trailer into the new 7-way, and you should be good to go. Your vehicle should now recognize the trailer.
    view full answer...

  • Parts Needed For LED Trailer Lights to Work in Combination with a 2011 BMW X5 with LED Tail Lights
  • Great news, I can help you figure out what you will need for your LED trailer lights to work in combination with your 2011 BMW X5 LED lights. If you have a factory 7-way installed on your vehicle from the manufacturer, then you may need one of the two adapters # C57003 or # 20142 you referenced. Both would work and complete the same function, the Tow Ready # 20142 is a popular option among our customers. If you happen to have an aftermarket one like our # 119190KIT that has a power...
    view full answer...

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Info for this part was:

Expert Research:
Michael H

Installed by:
Jeff D

Expert Research:
Jameson C

Expert Research:
Adam R

Updated by:
Rachael H

Expert Research:
Jeffrey L

Updated by:
Sarah W

Photos by:
Melissa S

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