107
Prestigio Cavaliere 141
Technical Service Manual
Symptom:
There is no display on LCD although power-on-self-test is passed.
8.4 VGA Controller Failure LCD No Display
Connect the I/O device & cable
to the M/B one at a time to find
out which part is causing the
problem.
1. Confirm LCD panel or monitor is good
and check the cable are connected
properly.
2. Try another known good monitor or
LCD module.
Replace faulty
LCD or monitor.
Check if
MB:U505,U503 J1, J2,
Charge BD: J2,J1
are cold colder?
VGA Controller Failure
Display
OK?
Remove all the I/O device & cable from
motherboard except LCD panel or extended
monitor.
Display
OK?
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:
TX
TXOUTCLK1-
TXOUT10-
TXOUT11-
TXOUT12-
FPVCC
+3V_LCDVCC
Board-level
Troubleshooting
Replace
Motherboard
Yes
No
PANEL_ID0
PANEL_ID1
PANEL_ID2
VGA_ENABLE
PCIRST#
ENBL
BLADJ
H8_ENBL
U505
U503
U13
Q1
Q2
Q3
RP1
R1
R3
Inverter BD
F1
D1
D2
L1
L3
R11
R2
R8
C199