Undetermined Problems
You are here because the diagnostic tests did not identify
which adapter or device failed, installed devices are
incorrect, a short circuit is suspected, or the system is
inoperative. Follow these procedures to isolate the failing
FRU (never replace nondefective FRUs).
Verify that all attached devices are supported by the
computer.
Verify that the power supply being used at the time of the
failure is operating correctly. (See “Power Systems
Checkout” on page 533.)
1. Power off the computer.
2. Check the cables, wires, and connectors for short
circuits and open circuits. Visually check them for
damage. If any problems are found, replace the
FRU.
3. Remove or disconnect all of the following devices:
a. Non-IBM devices
b. Devices attached to the expansion bus
connector
c. Printer, mouse, and other external devices
d. Battery pack
e. Hard disk drive
f. Diskette drive, CD-ROM drive, or DVD drive
g. DIMM
h. PC Cards
4. Power on the computer.
5. Determine if the problem has changed.
6. If the problem does not recur, reconnect the removed
devices one at a time until you find the failing FRU.
7. If the problem remains, replace the following FRUs
one at a time. Do not replace a nondefective FRU.
DC/DC card
Video card
LCD unit
System board
CPU card
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