109
Prestigio Cavaliere 141
Technical Service Manual
Connect the I/O device & cable
to the M/B one at a time to find
out which part is causing the
problem.
Remove all the I/O device & cable from
motherboard except monitor.
1. Confirm monitor is good and check
the cable are connected properly.
2. Try another known good monitor.
Display
OK?
VGA Controller Failure
Display
OK?
Replace faulty monitor.
Yes
No
Yes
No
Yes
Re-soldering.
No
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:
Check if
U505, J504
are cold solder?
VGA-DDCK
VGA_DDDA
VGA_VSYNC
VGA_HSYNC
VGA_RED
VGA_GREEN
VGA_BLUE
CRT_IN#
L11
RP502
Q13
Q10
Q9
Q14
R41
R62
R552
Board-level
Troubleshooting
Replace
Motherboard
M/B
U505
J504
FA501
CP503
CP502
CP1
L10
L14
L12
Symptom:
The CRT monitor shows nothing or abnormal color, but it is OK for LCD.
8.5 External Monitor No Display