AOC LV20E351, Service Manual

Page: 14 / 70

14
5. Trouble Shooting
5-1 Panel Control Circuit
No Display
Replace panel or FFC
cable to panel
Replace L118, C137
Check U300 crystal
X300 (12MHZ)
Replace X300
Check 2.5V L301-L304
3
3
.
.
3
3
V
V
L
L
3
3
0
0
5
5
-
-
L
L
3
3
0
0
8
8
Replace components
if it has problem
Replace U300
OK
OK
OK
OK
NG
NG
NG
NG
Check CN101 pin 42-45
is 5V and signal on pin
35,37,39,40,25-28,30-33,15-
18,20-23,5-8,10-13
Check U300 Output to
CN101 relative circuit and
CN101 VCC at Q300,
Q301, L309 (5V)