IBM ThinkPad R30 Hardware Maintenance Manual page 59

meaning of each icon:
7
6
Symbol
(1) Drive in use
(2) Numeric lock
Color
Green
Green
MT 2656, 2657, 2676
Meaning
Data is being read from or
written to the hard disk. Do
not enter standby mode or
power off the computer
when this indicator is on.
The numeric keypad on the
keyboard is enabled. You
enable or disable the
keypad by pressing and
holding the Shift key, and
pressing the NumLk key.
For details, see the User's
Reference.
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