I need help with my 2007 prius. It is a very cold day (5 F) and it won't start. I pushed the button as usual- first time the keys were still in the house and it did give the indication. Then the panel lit up normally but wouldn't go into reverse. Then I tried shutting down, had to hit the button a few times, and now all I get is the check engine light and a fan is running somewhere. The other thing to note is there was a beeping when I opened the door when I first got in and was running around getting the keys etc. I have two little ones who don't like me to spend time on the computer, so I did a quick look around here and saw that the red triangle symbol with the exclamation point means the 12 volt battery is low. I get that warning on and off for probably at least a year... couldn't find any information on it in the manual so I was just ignoring it. Does this mean my 12 volt is completely dead? Is that the hybrid battery or the regular battery like in a regular car? Please help! Thanks!