The green light on the back of the iLs Amplifier will turn off when it has reached a full charge.

iPod Classic – The iPod Classic will show a picture of a solid green battery in the top right corner if turned on, or if the unit is off but plugged in, the screen will show a green battery on the screen indicating the charge status.

iPod Touch – The iPod Touch will show a picture of a solid white battery in the top right corner if turned on, or if the unit is off but plugged in, the screen will show a green battery on the screen indicating the charge status.