I Am Looking For A 7 Pin To 4 Flat Adapter For My 2012 Mercedes ML350
Updated 06/30/2025 | Published 06/20/2025 >
Question:
I am seeking a 7 pin to 4 pin adapter for my 2012 Mercedes ML350, which has Burned-out bulb detector and a digital system. All I have tried give an error message for Right turn signal, Left turn signal, or Lighting signal. Which one will work?
asked by: John W
Expert Reply:
Hey John,
IF your Mercedes ML350 has that factory 7 way any adapter that plugs into the 7 way is going to work for you. I recommend the Curt # C35FR for your vehicle. This will simply plug right into your 7 way and give you a 4 flat connection for your trailer. It is specifically designed for vehicles like your Mercedes, and common vehicles with the same issues you are seeing.
What are you towing with that vehicle?
Product Page this Question was Asked From
7-Way to 4-Way/5-Way Trailer Adapter for Vehicles with Lamp-Out Sensors Towing Trailers with LEDs
- Custom Fit Vehicle Wiring
- Wiring Adapters
- Universal Fit
- 7 Blade to 4 Flat
- 7 Blade to 5 Flat
- Plug Only
- CURT
more information >
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John W.
6/25/2025
Towing FR Mini Lite 2506. I have personal knowledge that 'any adapter' will work is not the case. The Mercedes digital lighting control system expects to see analog current draw on its circuits. My digital trailer lights do not draw enough current for the Benz to properly detect and energize. How I know this for a fact is that the cheapo 7 to 4 converters (I bought 2) cause an error message, indicating a problem with the various lights - Check Left signal, Right signal, 'Lighting'. The Curt has built-in resistors to compensate. So, now you are more of an Expert...