Ever since we dropped down below zero in Wisconsin, my 2000 NB has had to be jump-started when it hasn't been driven for a day or two. The battery was brand new in March, 2011. Auto Zone tested it and said it had full cold-cranking power, but the problem persists. All the other electrical features work fine, it just won't start without a jump. This may sound dumb, because I have no mechanical aptitude, but could something other than the battery be causing this? I hope it's not the alternator!