NightHawk wrote:I recommend using a cheap 12v battery maintainer device as well as keeping a good 12v battery charger in your garage for emergencies.
I have those, plus also a portable 12v battery jumper device (uses a Lithium Ion battery) but haven't needed to use it since the only time I've experienced a few of those unexplained 12v battery discharges have been when the car was sitting in my garage. I do keep a small 12v voltmeter device plugged into the car's 12v accessory port so I can try to see if the voltage has dropped before it gets so low the car won't turn on.
I have those and recommend them too. Unfortunately my 12v battery has either been fully charged or flat dead at 6-7 volts, nothing in between. So thevolt meter does little good since it's already apparently dead when you open the door and the lights don't come on. When you get the text that your battery is low it's already dead.
I got an update from the dealer that "a module is drawing down the 12v" They're still doing diagnostics I assume to figure out which module. or maybe why. I'm gonna take a wild guess that its the ABS module going south. I vaguely recall reading someone else having a similar problem but I can't seem to find that thread now. Sorry OP I didn't mean to threadjack here.