![background image](http://html.mh-extra.com/html/viewsonic/vlcds27955-1w/vlcds27955-1w_service-manual_1021334016.webp)
NO POWER
D
Use multi-meter to measure
& turn on system
12V ok ?
5V ok ?
3.3V/2.5V
ok ?
Yes
Yes
Remove adapter
Measure adapter only
Adapter ok
Change adapter
M12V to
GND
Yes
No
Remove
FB4/FB7/D33
No
5V ok ?
Yes
No
+5V short to
GND or 3.3V
+12V->5V
regulator CKT no
work
No
3.3V/2.5V short
to GND
MCU 3.3V bad
Yes
PC 5V/DC 3.3V
CKT not correct
13
ViewSonic
Corporation
Co
nfidential
-
Do
Not
Copy
VG510b/s