12V ok ?
5V ok ?
No
Yes
Adapter ok
Yes
MCU 3.3V bad
M12V to
GND
Change adapter
Remove adapter
Measure adapter only
Yes
3.3V/2.5V
ok ?
Yes
No
+12V->5V
regulator CKT no
work
Yes
3.3V/2.5V short
to GND
+5V short to
GND or 3.3V
5V ok ?
No
Remove
L11/L15/L16/L25
Use multi-meter to measure
& turn on system
No
PC 5V/DC 3.3V
CKT not correct
NO POWER
D
13
ViewSonic
Corporation
Co
nfidential
-
Do
Not
Copy
VG511s
VG512s