IBM ThinkPad 600, Hardware Maintenance Manual

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Checkout Guide
If the internal keyboard does not work or an unexpected
character appears, make sure that the flexible cable
extending from the keyboard is correctly seated in the
connector. If the keyboard cable connection is correct, run
the keyboard test. See “Running the Diagnostics” on
page 40 for details.
Note
When the Fn key is pressed, a black square briefly
appears.
If the tests detect a keyboard problem, do the following
one at a time to correct the problem. Do not replace a
nondefective FRU:
1. Reseat the keyboard cable.
2. Replace the keyboard.
3. Replace the card that the keyboard is connected to.
4. Replace the system board.
The following auxiliary input devices are supported for this
computer:
Ÿ
Numeric keypad
Ÿ
Mouse (PS/2 compatible)
Ÿ
External keyboard (with keyboard/mouse cable)
If any of these devices do not work, reseat the cable
connector and repeat the failing operation.
If the problem does not recur, recheck the connector. If
the problem is not corrected, replace the device and then
the card that the devices are directly connected to.
Memory Checkout
DIMM cards are available for increasing memory capacity.
The memory size is displayed in kilobites. 576 KB is
reserved by the system, so you calculate the memory size
by the following equation:
[total memory size (MB)]
×
1024
−
576 (KB)
For example, if the total memory size is 64 MB, it is
displayed as 64960 KB.
Memory errors might stop system operations, show error
messages on the screen, or hang the system.
Use the following procedure to isolate memory problems:
1. Power off the computer and remove any installed
DIMM from its slot.
Note
If the computer has a base memory slot and
option memory slots, remove any DIMMs
installed in the option memory slots.
General Descriptions
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