Originally Posted by ric124
So last night I tried a few different ways to replicate what the OP did and the only way this is possible is to have engine running, get out and lock the doors. Then the engine will remain running. Not trying to be an ass but just maybe OP rushed out of his car thinking he had shut it off and locked the doors.
That's a bit what I was thinking.. the 328i is very silent and I have had it myself once or twice that the engine was still running when I closed the doors.. I noticed it because the alarm didn't beep when I locked the doors. I can imagine, if you don't have the alarm, you might get into such a situation.