SheroBee, Yes, I was referring to the standard 12v battery under the hood. I know mine was weak and the only symptom I had was the Assist wasnt coming on all that often and mpg were about 4 lower than usual.

Here in Florida, 12v batteries dont last that long so I wasnt all that surprised.

GeorgeJ who also replied has some valid thoughts on why the auto stop wasnt working, I know my Prius acted as he suggests yet never noticed this on the HAH yet. We dont use the defog/defrost mode much if ever, but will try it over the weekend on our next road trip.