I think it complains for some reason just for opening the door before you turn it off. As in open door, power down, get out, close door, beep beep. I know I keep catching myself sometimes forgetting to shut the car off and opening the door and then remember I have to shut the door to turn it off "cleanly" or something. But yeah no clue what the complaint is for, and haven't done it recently enough (or spent time experimenting) to find out all the detailed conditions for beep starting/stopping.