[. . . ] Align the battery pack with its metal contacts facing front, and slide it into the charger. [. . . ] If the POWER lamp does not light when you turn on the power, check the power cord connection. â· If the CHARGE lamp does not light at the start of charging, make sure the battery pack is firmly mounted into the charger. â· When a fully charged battery pack is placed in the charger, the CHARGE lamp turns on and then off. â· When you are charging a battery pack that has not been used for a long time, the CHARGE lamp may blink for a while. [. . . ] 5 hours for a fully discharged battery pack to return to a fully charged state. [. . . ]