Originally Posted by kaorisdad
I usually don't lock my cars in my garage. When I bought my new A6, the salesperson suggested that the car always be locked as some systems are continually on only while unlocked. He said if I didn't, my battery would be drained if I went on vacation.
Does anyone know what additional systems are left on while the car is unlocked?
I don't believe there's any significant energy advantage to either locking or unlocking the car. The car has stages of power saving modes where if it's not turned on for a period of time, systems are put into "sleep" mode. An example of this is if the car has been off for awhile, the MMI goes through a longer, full startup. Another would be the requirement of pulling the door handle twice to unlock the car - once to wake the locking system and another to unlock the door.
On the other hand, it's not a bad idea to lock the car at all times, even in a locked garage (although I'm guilty of usually not doing so).