IBM THINKPAD S05L-1270-01 - Manual (Page 157)

Symptom / Error FRU / Action in Sequence
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 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. DC/DC card
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
3. System board
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
LCD has extra horizontal or
vertical lines displayed. LCD assembly
Keyboard or TrackPoint III Related
Symptoms
Symptom / Error FRU / Action in Sequence
Keyboard (one or more
keys) does not work. 1. Reseat the keyboard
cable on the system
board.
2. Keyboard
3. System board
ThinkPad 560, 560E (2640) 145