[noizejoy]

> With my car, trying to lock the doors just doesn't work if one is left open

for suburban single family residence dwellers with their own garage, they may not always (or ever) lock the doors while the car is parked in their locked garage.

[WirelessGigabit]

Which is one of the things one must absolutely do to ensure all modules go to sleep.

[Kirby64]

No car I'm aware of requires this. If the ignition is off and the doors are all closed, the car is, for all intents and purposes, asleep. If anything, doors unlocked may be lower power... as that would disable (or, rather, not enable) alarm functionality.

[dcormier]

The author of the linked article mentions a couple of times to lock the doors for the car to go to sleep properly.