Thanks for your reply. The technician did the jump starting as the last resort. Is it possible that there might be a problem with the electronic key?
I am not too happy with the service department. From what they told me they work on a "flat rate", They get paid for half an hour by Mercedes to diagnose the problem. They connect the car to the computer and if they don't get any error codes, they assume there is no problem. would any of the things that you mentioned show an error code?