My car sat for 2 weeks in extremely cold weather. Got a jump, started fine. 3 days later, dead again. Got a new battery (car was less than 4 years old and replacement battery was less than 2).
One blizzard later, after the car sat again for 9 days, wouldn't start. Towed to mechanic who said there was a short in the dome light. Recommended disconnecting. Said radio would have to be rewired as it was on the same fuse.
Now, auto door locks don't work from fob. Clock resets to 1: 00 and trip odometers reset to 0 every time key is turned off. Radio presets reset as well.