![background image](http://html1.mh-extra.com/html/viewsonic/va912-4/va912-4_service-manual_1020986055.webp)
No power
OK
No Power
Check U1 pin2
Output 3.3V?
Change power
board module
Check X’tal Y1=24.576MHz?
And Y2=11.092MHz?
Check U3 pin 2
Output 2.5V?
Change U1.
Change U3
Change Y1 or Y2
Change M/B
Check CN1 pin 5,6
5V correct?
OK
OK
OK
No
No
No
No
Check button cable
& button board?
OK
Change cable or
button board
No
6
.
Troubleshooting
52
ViewSonic
Corporation
Co
nfidential
-
Do
Not
Copy
VA912-4_VA912b-4