Lenovo 07632VU, Hardware Maintenance Manual

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LCD-related symptoms
Important
The TFT LCD for the notebook computer contains many thin-film transistors
(TFTs). The presence of a small number of dots that are missing, discolored,
or always lighted 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:
v
WXGA: 8 or more bright dots, 8 or more dark dots, or a total of 9 or more
bright and dark dots.
Note: A bright dot means a pixel is always on (white or color.) A dark dot
means a pixel is always off (black color.)
Symptom or error FRU or action, in sequence
No beep, power-on indicator on, and a
blank LCD during POST.
System board .
v
LCD backlight not working.
v
LCD too dark.
v
LCD brightness cannot be adjusted.
v
LCD contrast cannot be adjusted.
1. Reseat the LCD connectors .
2. LCD assembly.
3. System board.
v
LCD screen unreadable.
v
Characters missing pixels.
v
Screen abnormal.
v
Wrong color displayed.
1. See important note for “LCD-related
symptoms.”
2. Reseat all LCD connectors.
3. LCD assembly.
4. System board.
Horizontal or vertical lines displayed on
LCD.
LCD assembly .
Symptom-to-FRU index
40
MT 0763 and 0764