LED Trailer Tail Lights Will Not Work when Connected to a 2009 Mercedes GL550 with Factory 7-Way

Updated 09/30/2013 | Published 09/28/2013

Products Featured in This Question

7-Way to 4-Way/5-Way Trailer Adapter for Vehicles with Lamp-Out Sensors Towing Trailers with LEDs

(147)

$24.94

7-Way Trailer Adapter for Towing Trailers with LED Lights

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$38.17

Question:

Hi, I have 2009 MB GL550 and recently tried to rent a trailer to haul my motorcycle. Upon hooking up the trailer, we discovered the LED lights on trailer would not light. The team at the rental place mentioned they get there was a problem with some Euro manufacturers and LED. I researched the problem on MBZ forums and was directed here. I have a factory hitch with the 7way adapter. Do you have a converteri to solve the LED issue. I generally convert to 4way flat style as I think most trailers have. By the way, no LED lights work just fine on my hitch. Its just that many rental places have moved to LEDs. Help?

asked by: Jamie F

Expert Reply:

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, # C35FR, 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 on a vehicle to a 4-Way or 5-Way flat on a trailer. We also have # C57003 to go from a 7-Way to a 7-Way.

expert reply by: Michael H