No beep symptoms, Lcd-related symptoms – IBM THINKPAD 760C/CD (9546) User Manual

Page 298

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No Beep Symptoms

Symptom / Error

FRU / Action in Sequence

No beep, power-on indicator
not on, and a blank LCD
during POST.

1. Go to “Power

Systems Checkout”
on page 272.

2. System Board
3. Power sources

No beep, power-on indicator
on, and a blank LCD during
POST.

1. System Board

No beep, power-on indicator
on, and a blinking cursor
only during POST.

1. System Board

No beep during POST but
system runs correctly.

1. Turn the volume up

and check the
speaker.

2. Speaker
3. System Board

LCD-Related Symptoms

Important

The LCD for the notebook computer contains over
921 000 thin-film transistors (TFTs). A small number
of missing, discolored, or lighted dots (on all the time)
is characteristic of TFT LCD technology, but excessive
pixel problems can cause viewing concerns. The LCD
should be replaced if the number of dots satisfies the
following condition:

The number of missing, discolored, or lighted
dots in any background is 21 or more.

Symptom / Error

FRU / Action in Sequence

No beep, power-on indicator
on, and a blank LCD during
POST.

1. System Board

LCD backlight not
working, or

LCD too dark, or

LCD brightness cannot
be adjusted, or

LCD contrast cannot
be adjusted.

1. Reseat the LCD

connectors.

2. LCD Assembly

LCD screen
unreadable, or

Characters missing
pels, or
Screen abnormal, or
Wrong color displayed.

1. See important note

for “LCD-Related
Symptoms.”

2. Reseat all LCD

connectors.

3. LCD Assembly
4. System Board

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IBM Mobile Systems - ThinkPad HMM Volume 3

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