Symptom/Error
FRU/Action
Serial or parallel port device
problems.
1. Device
2. Cable
3. System Board
4. Serial Adapter (if
attached)
5. I/O Panel Assembly
Internal Data/Fax modem
does not communicate with
a remote modem or a fax.
1. See “Fax/Modem
Checkout” on
page 466.
Undetermined Problem
You are here because the diagnostics tests did not identify
the failing FRU.
Check the power supply in use (see “Power Systems
Checkout” on page 117). If the power supply is operating
correctly, return here and continue with the following
procedure.
1. Power-off the computer and remove the battery packs
from the computer.
2. Remove or disconnect one of the following devices or
adapter (do not isolate FRUs that are known to be
good).
a. Non-IBM devices
b. Modem, printer, mouse, or other external device
c. IC DRAM card
d. Hard disk drive (fixed disk drive) or diskette drive
e. Communications cartridge
f. Any adapter and device
3. Power-on the computer and start the system program.
4. Press Ctrl
+
A to run the system checkout. Do not
configure the computer. If diagnostics cannot be
loaded from the hard disk, try and load them from the
Reference Diskette. Test only those adapters and
devices still attached to the computer.
5. If the symptom remains, repeat steps 1 through 3
until you find the failing FRU or until all FRUs have
been removed.
6. If all of the FRUs listed have been removed and the
problem remains, replace the system board.
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IBM Mobile Systems HMM - Volume 1
