Service manual

133
8575
8575
A N/B Maintenance
A N/B Maintenance
Replace faulty
LCD or monitor.
Check if
U504, J3 are cold
solder?
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.
Display
OK?
Remove all the I/O device & cable from
motherboard except LCD panel or extended
monitor.
Display
OK?
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.
Parts: Signals:
TX2OUT[0:2]+
TX2OUT[0:2]-
BLADJ
KH8_ENABKL
-LID
Board-level
Troubleshooting
Replace
Motherboard
Yes
No
U4
U504
U509
J3
J7
PJ2
J6
Q503
F503
L504
Q2
R828
R829
R830
L514
L512
L513
L515
SW1
R511
+3VS
LCDVCC
ENAVDD
PID[0:2]
TXCLK+
TXCLK-
TX2CLK+
TX2CLK-
TXOUT[0:2]+
TXOUT[0:2]-
8.3 VGA Controller Failure LCD No Display
There is no display or picture abnormal on LCD although power-on-self-test is passed.