IBM A21M, A22P, A22M, A21P, A20M, MT 2631 manual LCD-related symptoms, Connectors

Symptom-to-FRU index

LCD-related symptoms

Important

The TFT LCD for the notebook computer contains many thin-film transistors (TFTs). 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:

vSVGA: 5 or more bright dots, 5 or more dark dots, or a total of 9 or more bright and dark dots.

vXGA: 8 or more bright dots, 8 or more dark dots, or a total of 9 or more bright and dark dots.

vSXGA+: 11 or more bright dots, 13 or more dark dots, or a total of 16 or more bright and dark dots.

vUXGA: 11 or more bright dots, 16 or more dark dots, or a total of 16 or more bright and dark dots.

Note: A bright dot is a white or colored pixel that is always on. A dark dot is a pixel that is always off and shows as black.

Symptom or error		FRU or action, in sequence
No beep, power-on indicator		System board.
on, and a blank LCD during
POST.
v LCD backlight not working.		1.	Reseat the LCD
v	LCD too dark.		connectors.
v LCD brightness cannot be		2.	LCD assembly.
	adjusted.	3.	System board.
v LCD contrast cannot be
	adjusted.
v	LCD screen unreadable.	1.	See important note for
v	Characters missing pixels.		“LCD-related symptoms”.
v	Screen abnormal.	2.	Reseat all LCD connectors.
v	Wrong color displayed.	3.	LCD assembly.
		4.	System board.
Horizontal or vertical lines		LCD assembly.
displayed on LCD.

54ThinkPad A20m/p, A21m/p, A22m/p