Dell Inspiron 4100 - Manual (Page 65)

The green lights located above the keyboard indicate the following:
Microphone
Record audio with the internal microphone.
Device Status Lights
l The light turns on when the computer is turned on.
l The light turns on when the computer reads or writes data.
l The light turns on steadily or blinks when the computer is in a power management mode. It also blinks to indicate battery charge status.
If the computer is connected to an electrical outlet, the light operates as follows:
¡ Flashing green: The battery is fully charged.
¡ Solid green: The battery is charging.
If the computer is running on a battery, the light operates as follows:
¡ Off: The battery is adequately charged.
¡ Flashing orange: The battery charge is low.
¡ Solid orange: The battery charge is critically low.
Touch Pad
Keyboard Status Lights
Turns on when the numeric keypad is enabled
Turns on when the uppercase letter function is enabled
Turns on when the scroll lock function is enabled
NOTICE: To avoid data loss, never turn off the computer while the light is flashing.