Actually, one short press will stop the engine but leave the stereo on. Pressing again will re-start the engine. If you want to kill everything right away, press and hold the start button for a one-thousand two or three count. That will kill the engine and shut down the stereo etc. As for the stereo staying on, I have found that even if I use the short press and the stereo remains on, locking the car turns everything off...

 

so to really power down immediately and then restart (for example, to restart the navigation after hickups) I would have to stop the car (duh...) keep the button pushed. release and short push for starting up again?

would be interesting as sometimes the traffic info isn't used in the route planning. Now I have to do without till the end of my trip. Next start (return trip) all is working again. Kind of irritating not to have a reset or real power down button.

 

The second press will turn off the car if you don't have the brake depressed...I agree that it's usually easier to simply press and hold it one time to shut things down.

You can restart the iDrive system (including the navigation system) by performing the equivalent of a control-alt-delete. Press and hold the radio mute button with your thumb then press both disc eject buttons at the same time with your fingers and it'll reboot things without having to turn the car off and back on again...

 

that would be for the professional version. Sorry I wasn't more accurate, but I have the business system (one DVD drive only, not two)

 

Doh! Didn't think of taking the foot off the brake! Simply held the button down to shut down completely...