IBM X24, X23, X22, X20, X21 manual LCD-related symptoms, Intermittent problems

The power-on password prompt	A power-on password or a
	supervisor password is set.
	Type the password and press
	Enter.
The hard disk password prompt	A hard disk password is set.
	Type the password and press
	Enter.
The DOS-full screen looks	Start the ThinkPad
smaller.	Configuration program and set
	the Screen expansion
	function.

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(X20, X21): 5 or more bright dots, 5 or more dark dots, or a total of 9 or more bright and dark dots.

vXGA(X22, X23, X24): 8 or more bright dots, 8 or more dark dots, or a total of 9 or more bright and dark dots.

Symptom or error		FRU or action, in sequence
No beep, power-on indicator		1.	System board.
on, and a blank LCD during
POST
v	LCD backlight not working	1.	Reseat the LCD
v	LCD too dark		connectors.
		2.	LCD assembly.
v	LCD brightness cannot be
	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″.
		2. Reseat all LCD connectors.
v	Screen abnormal
		3.	LCD assembly.
v	Wrong color displayed
v	Horizontal or vertical lines	1.	LCD assembly.
	displayed on LCD

Intermittent problems

Intermittent system hang problems can be due to a variety of causes that have nothing to do with a hardware defect,

52ThinkPad X20, X21, X22, X23, X24