What's up buddy. I saw you posted about 2 years ago about the fog light conversion I have a 2010 C350 same body style as you. In 2011 Our body style came in LED fog lights. As long as you have the sport bumper it's an easy conversion. If you have instagram visit allinonestopshop, they have before and after pictures on my car.
Here is a link to the foglights and they come with a wire that prevents error codes. Hope this helps.
OEM Style Mercedes W204 C300 C350 LED Daytime Running Lights
Here is a link to the foglights and they come with a wire that prevents error codes. Hope this helps.
OEM Style Mercedes W204 C300 C350 LED Daytime Running Lights