I have a strange one. It happened a couple of time in the last 2 days. I parked the car, everything seems normal, but when I return in a few minutes time, the car won't even start - it does not even crank. The LED lights up as usual.
After a minute or two again, it starts and runs with no problem.
(I don't know what to do with myself if I don't have a mercedes or a glass of nice wine anymore)