Hello all,

I posted recently about my Prius suddenly failing to start and the general consensus was that it was probably a problem with the 12v battery in the trunk. I called my local dealership and they say that there are two types of Prius backup batteries: The old type (which they aren't even sure they have in stock) costs $130. The service guy said that that would be fine in Florida or something, but that in New England the old type doesn't deal well with the cold weather and that I should really get the new type, which is $450. Yikes.

So first, I wanted to get some advice about whether this is all on the level or if this guy is just trying to sell me the more expensive battery.

Second, I wanted to know if there is an easy way to visually tell which type of battery is currently in my car. According to the auto history I looked up on it before buying the car had only one prior owner who lived in New York, which means that either it's got an old-style battery that has weathered several winters without issues or it's got a new-style battery that still managed to fail. Either way there's reason for me to be concerned.

Finally, we are fairly sure that no lights or anything were left on nor did the alarm go off. It's as though the battery just spontaneously died. Wouldn't that be indicative of a more fundamental problem or can cold weather really just kill the battery like that?

Thanks again!