Lenovo 2529E8U, 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 as follows:
Minimum quantity of defective pixels required for LCD replacement on June 2006 or later
manufactured ThinkPad
LCD resolution Bright dots Dark dots Bright and dark dots
XGA, WXGA 5 6 6
WXGA+, SXGA+,
WSXGA+
5 8 10
UXGA, WUXGA,
QXGA
5 13 13
Notes:
1. Lenovo will not provide replacement if the LCD is within specification as we
cannot guarantee that any replacement LCD will have zero pixel defects.
2. A bright dot means a pixel is always on (white or color.)
3.
A dark dot means a pixel is always off (black color.)
4. One pixel consists of R, G, B sub-pixels.
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
ThinkPad Z60m
51