One problem related to software has been reported for the 2009 Mercedes Benz C300. The most recently reported issues are listed below.
The vehicle would not accept the computer chip key pod and the car was completely disabled, steering lock assembly had an electrical fault. The car was completely locked up, unable to turn ignition on. No advance notice that this was a problem. The car had to be towed to a mercedes dealership for repair, almost 50 miles at a cost of $240. The repair was $707. 00 and involved replacement of steering column lock assembly. This was not covered under warranty by mercedes and they have not announced a recall even though this problem seems prevalent on the internet. The safety issue is having a vehicle that cannot be operated, nor repaired by anyone other than an authorized mercedes dealership. This problem strands the driver at a place wherever the problem may occur. I had the dealership return the faulty part if NHTSA would like to inspect it. The Mercedes Benz steering column lock problem is not from wear and tear, more likely a software problem between the ignition and the key. As a consumer, I feel ripped off to the tune of $1,000 to pay for a problem that mercedes knows about, yet has not initiated a recall to repair the fault.