Front Left SRS Malfunction/ Need Help on Repair
 

My C300 2009 has a front left srs malfunction message on the dash. I also noticed my driver side seat belt had no tension and is very loose compared to the passenger side. The seatbelt doesn’t retract when taking it off. I’m thinking it is the seat belt tensioner causing the srs message. I want to know if I could buy a used one and will I need a scan tool to reset the srs message or will it turn off with the repair done. Also I still have to complete the driver and passenger side airbag recall. I don’t know if that’s causing the srs message. Thanks for the help

Before you go replacing part, why don't you have the car scanned? Then you can decide what to change.