Failure to follow these instructions could result in damage to your equipment and may void your warranty. Replacing the battery requires four basic steps: · Turn off the computer or put it in sleep mode. · Open the expansion bay. · Remove the installed battery. · Insert the replacement battery. Note: A video version of the replacement instructions is available at http://www. apple. com/installparts Tools Required No tools are required for this procedure. About Batteries Battery and Dual Battery Support When the external power adapter is not connected, your computer draws power from a PowerBook battery in the battery bay or expansion bay. You can also insert a second battery in the expansion bay to double the amount of battery life. Monitoring Battery Charge Level You can determine the charge left in your battery by looking at the battery level indicator lights on the battery itself. The charge can be checked whether the battery is in the PowerBook or not. The lights glow to show how much charge is left in the battery. A lighted circle indicates that the battery has power; an unlighted circle indicates lack of charge. The indicator lights remain lit for a few seconds after you press the battery level indicator button. If only one flashing light is on, very little charge is left in the battery. Plug in the power adapter. Fully charged 3/4 charged Battery level indicator button Battery level indicator lights 1/2 charged 1/4 charged Note: The battery level indicator lights stay on while the battery is being charged by the external power adapter. When the battery is fully charged, the lights turn off. Charging a Battery When the power adapter is connected, the battery is recharged whether the computer is off, on, or in sleep. However, the battery will recharge more quickly if the computer is off or in sleep...