I'd like to clarify that I use an external timer to shut off power to my Leviton L2 charger during non off-peak times (0600 to midnight). I'm guess that combination creates a load on the 12 volt battery if others don't have the same problem. I don't trust the timer on the car....at all.
I have found two ways to drain the 12 volt battery; 1) not putting it in Park when you turnoff the car, 2) leaving it on a charger over the weekend and not driving it (I have a Leviton L2 charger).
Ever since I avoided the two conditions above, I have not had any problems.
My 12 volt battery has been draining over the weekend while attached to my level 2 charger. For two weekends in a row now the 12 volt battery is almost dead and the car won't start. The charger is set to charge midnight to 6:00 am for off peak rates. The Sunday night charge would be to a...