Symptom-to-FRU Index
The Symptom-to-FRU Index lists symptoms and errors and
the possible causes. The most likely cause is listed first.
If the computer displays an error message, first replace
FRUs listed in the error message. An
X in an error
message can be any number.
Note: If you have an IBM device with its own service
manual or a device not supported by the advanced
diagnostics tests, refer to the manual for that
device.
Symptom/Error
FRU/Action
One or more keys do not
work.
(See “External
Keyboard/Auxiliary Input
Device Checkout” on
page 465 before replacing
any FRUs.)
1. Keyboard
2. System Board
No beep and a blank or
unreadable display during
POST.
(See “Power Systems
Checkout” on page 27
before replacing any FRUs.)
1. System Board
2. Any options or devices
3. Power source when
failing
4. Speaker
No beep with a normal
display during POST.
1. Speaker
2. System Board
Continuous beep
1. System Board
2. Any options or devices
Repeating short beeps.
(See “External
Keyboard/Auxiliary Input
Device Checkout” on
page 465 before replacing
any FRUs.)
1. System Board
2. Keyboard
Dew Point or Temperature
icon appears with one long
and one short beep.
1. System Board
2. Power source when
failing
One long and one short
beep.
1. System Board
2. Power source when
failing
One long and two short
beeps.
1. System Board
2. Power source when
failing
One short beep and a
blank, unreadable, or
flashing display with no
external display attached.
1. Display (LCD)
2. System Board
3. Power source when
failing
One short beep and
Diskette Prompt or a
program load from the hard
disk drive or unable to read
diskette(s).
1. Diskette Drive
2. System Board
3. Diskette Drive Cable
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IBM Mobile Systems HMM - Volume 1
