My 2000 CLK430 was driving fine until I pulled into a parking spot and left it idling for about 30 seconds while I looked at my phone. The car suddenly died and will not even crank over. All electrical seems to work such as lights and windows. I made sure the car was in park and even jiggled the shifter to make sure. What would make it shut off like that? Any help is certainly appreciated.
Thank you all in advance.
Boomhauer in Texas.

Same problem on my car turned out to be fuel pump relay was only using top half of the tank so when it got to 1/2 it ran out

I did some testing today. The car will start if I bypass the starter relay with a piece of wire. It runs, but runs really rough. It let me start it with the key once and now the key turns with doing nothing but energizing all the accessories. I can still bypass the relay and it spins the starter and starts. Why wont the key start it? I need to check the fuel pump and fuel pressure but that doesn't have anything to do with the key not spinning the starter does it?
Thanks,