Mercedes ML350 Does Not Work with a Trailer that Has LED Tail Lights
Updated 05/20/2025 | Published 05/01/2014
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Question:
Mercedes ML 350 does not power LED trailer lights This seems to be a common problem for MB, Audi, and VW but I have yet to hear of a fix. Would a powered taillight converter do the trick?
asked by: Don
Expert Reply:
German engineered vehicles such as your Mercedes ML350 do have problems with LED trailer lights. A powered converter could solve the issue but there are also special adapters that create more draw that will allow the affected vehicles to tow a trailer with LED lights and not have that bulb out sensor issue.
I would need to know the year of your Mercedes ML350 to make a wiring harness recommendation.
You would need to have a 7-Way wiring harness on the vehicle already to use the adapters. For the adapters there is a 7-Way to 7-Way, # 20142 and a 7-Way to 4- and 5-Way # C35FR.
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
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Del
5/20/2025
I think I have this issue with a 2010 ML350. I added a factory trailer hitch and have had the new SAM programmed. Could be a programming issue, but I'm thinking it's an issue with the leds. There is power to the 7-way connector. Thanks.