Symptom-to-FRU Index
The Symptom-to-FRU Index lists error symptoms and
possible causes. The most likely cause is listed first.
Always begin with “General Checkout” on page 112. This
index also can be used to help you decide which FRUs to
have available when servicing a computer.
If you are unable to correct the problem using this index,
go to “Undetermined Problem” on page 130.
IMPORTANT:
1. If you have both an error message and an incorrect
audio response, diagnose the error message first.
2. If you cannot run the advanced diagnostics tests, but
did receive a POST error message, diagnose the
POST error message.
3. If you did not receive an error message, look for a
description of your error symptoms in the first part of
this index.
4. Check all power supply voltages before you replace
the system board. (See “Power Systems Checkout”
on page 117.)
5. If an error message is not listed, there is a device
installed that requires an additional diskette or service
manual. Refer to the diskette or service manual for
that device.
How to Read POST Error Messages
POST error messages are displayed on the screen as 3, 4,
5, or 8 digits. The error messages that can be displayed
as shorter POST messages are highlighted in this
Symptom-to-FRU Index.
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IBM Mobile Systems HMM - Volume 1
