Indicator lights can be on, off, or blinking. Indicator Condition Online On—the printer is online and ready to print jobs. Blinking—the printer is online and receiving or processing
data. Off—the printer is offline. Paper On—a 550-sheet paper tray is low or empty. Toner On—the toner supply is low. Attention Blinking—the printer requires attention. Off—the printer is operating normally. Using the Operator Panel Keys The operator panel keys enable you to configure and operate the printer. Online Use the Online key to take the printer offline, put it back
online, or exit menu mode.
Note:  If the printer is processing a job when you take it
offline, the printer displays a message that gives you the
option of canceling the job. Enter Use the Enter key to do the following:
v  Select an action menu item or a menu item value.     Note:  To select a new value for a menu item, you must
    press the Enter key when the value is displayed in the
    message display area. After you press Enter, an asterisk (*)
    appears next to the new value, indicating that it is active.
v  Continue printing when the printer displays a message that requires operator intervention (for example, TONER LOW). Menu Use the Menu keys to scroll up or down through the menu
list. As you scroll through the list, the current menu is
displayed in the message display area. Item Use the Item keys to scroll up or down through the list of
items for the menu listed in the message display area. As you
scroll through the list, the current item and, if applicable, the
current value for the item is displayed in the message display
area, just below the name of the current menu. You can also use the Item keys to scroll through a list of
operator panel messages when more than one message is
present. 22    Infoprint 21: User’s Guide