MiTAC 8050QMA - Manual (Page 116)

115
80 80 50QMA 50QMA N/B Maintenance N/B Maintenance
Display
OK?
Replace faulty
LCD or monitor. Display
OK?
VGA Controller Failure
LCD No Display
1. Confirm LCD panel or monitor is good
and check the cable are connected
properly.
2. Try another known good monitor or
LCD module.
Remove all the I/O device & cable from
motherboard except LCD panel or
extended monitor.
Connect the I/O device & cable to
the M/B one at a time to find out
which part is causing the problem.
Yes
No
Yes
No
Re-soldering.
One of the following parts on the mother-board may be
defective, use an oscilloscope to check the following signal or
replace the parts one at a time and test after each replacement.
Board-level
Troubleshooting
Replace
Motherboard
Yes
No
8.3 VGA Controller Test Error LCD No Display-1
There is no display or picture abnormal on LCD although power-on-self-test is passed.
Check if
J1, J2 are cold
solder?
Parts
U710
U709
U13
J506
J1
J2
J723
Signals
+3VS
LVDS_TX[0..2]+
LVDS_TX[0..2]-
LVDS_CLK+
LVDS_CLK-
LVDS_ENBKL
H8_ENABKL
Parts
L10~L13
SW1
R3
C1
R1
Signals
ENABKL
BLADJ
COVER_SW
Daughter Board Main Board
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