Yesterday morning, my sweetie went out to go to work, and the Prius wouldn't start, (or anything else). Jump starting remedied that, but I decided that the 12v battery was probably toast (people may remember that I had problems with it last winter). I bought a new battery, and then endeavored to put it in. The process was a pain (particularly since I was doing it outside in blowing snow), but I finally got the battery all exposed, only to discover that the battery was frozen into 1.5" of ice (of some sort). Three hours of hair dryer later, I had extracted the battery and all the ice, and installed the new battery. What a pain. Anyone have an idea what might have caused the problem, and how to avoid it in the future?
Yep. Living in Maine. Seriously though, there's got to be a leak somewhere in the hatch. Some people have found a slow leak in one of the metal seams in the channel just above where the hinges (for the hatch) are. In heavy rain it can gradually seep through there, and trickle down the inside of the panel to collect in the wheel arch compartment where the little battery is.