The charge of my Mac Book is stolen, but I forget when did it disappear. So try to check the log of OS. In application, find console, in /var/log, find "powermanagement":
Using AC(Charge: 76)
Using Batt(Charge: 66)
Another log is all message:
magsafeStateChange state changed old 2 new 1 //means swith from Batt to AC
magsafeStateChange state changed old 1 new 2 //from AC to Batt
From the log I know the I never use the charge form 5 days. Dammit! Don't let me catch u!
新年新气象，诸佛保佑，小人滚远点！