XGA: 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
on, and a blank LCD during
POST
1. System board.
LCD backlight not
working
LCD too dark
LCD brightness cannot
be adjusted
LCD contrast cannot
be adjusted
1. Reseat the LCD con-
nectors.
2. LCD assembly.
3. System board.
LCD screen unread-
able
Characters missing
pixels
Screen abnormal
Wrong color displayed
1. See important note
for "LCD-related
symptoms".
2. Reseat all LCD con-
nectors.
3. LCD assembly.
Horizontal or vertical
lines displayed on LCD
1. LCD assembly.
Intermittent problems
Intermittent system hang problems can be due to a variety
of causes that have nothing to do with a hardware defect,
such as: cosmic radiation, electrostatic discharge, or soft-
ware errors. FRU replacement should be considered only
when a recurring problem exists.
When analyzing an intermittent problem, do the following:
1. Run the diagnostic test for the system board in loop
mode at least 10 times.
2. If no error is detected, do not replace any FRUs.
3. If any error is detected, replace the FRU shown by
the FRU code. Rerun the test to verify that no more
errors exist.
Undetermined problems
You are here because the diagnostic tests did not identify
which adapter or device failed, installed devices are incor-
rect, a short circuit is suspected, or the system is inopera-
tive. Follow these procedures to isolate the failing FRU (do
not isolate FRUs that have no defects).
Verify that all attached devices are supported by the com-
puter.
Verify that the power supply being used at the time of the
failure is operating correctly. (See “Power system
checkout” on page 26)
1. Power off the computer.
40
ThinkPad X20
Summary of Contents for ThinkPad X20
Page 1: ...IBM Mobile Systems ThinkPad X20 Series computer Hardware Maintenance Manual June 2000 ...
Page 2: ...IBM Mobile Systems ThinkPad X20 Series computer Hardware Maintenance Manual June 2000 IBM ...
Page 3: ...i ...
Page 36: ...30 ThinkPad X20 ...
Page 58: ...1060 Mini PCI adapter Battery pack 1010 Keyboard assembly 1050 6 52 ThinkPad X20 ...
Page 60: ...1080 LCD assembly Battery pack 1010 Keyboard assembly 1050 1 ThinkP ad 2 54 ThinkPad X20 ...
Page 69: ...Step Screw quantity Torque 1 M2 3 5mm 2 BK 19 6 Ncm 2 kgfcm ThinkPad X20 63 ...
Page 71: ...1 Step Screw quantity Torque 1 M2 3 5mm 2 BK 19 6 Ncm 2 kgfcm ThinkPad X20 65 ...
Page 84: ...78 ThinkPad X20 ...
Page 86: ...IBM Part Number 19K6850 Printed in U S A 19K685ð ...