I would start with the most obvious - replace the battery. A battery that is cracked and corroding can cause havic on electronic components causing them to do unexplainable things. I know this is a MB, but a few days before the battery in my Durango took a dive, I was getting all kind of weird things going on - stalling, hesitating, certain idiot lights coming on for no reason, trans not shifting properly. A new battery put everything back to normal.

James