My Company tossed out 3 of these, and so far I have 2 working, and expect the third to be fixed tomorrow. Bad caps are the cause, but they cause the mosfet transistors to run hot and eventually short, which takes out the fuse for the back light circuit. See the solution below complete with digi key part numbers. This is provided for personal use and not for someone to make money selling the repair. It took some time to research the parts to fix this without a schematic. I am posting it here for others to fix their monitor and keep it out of the landfill. You must know something about electronics, or you can contact me, or someone else to perform this repair. Please help yourself but be considerate at the same time. Best regards, Ryan N7QJ
Repair for Viewsonic VA1912wb-3 widescreen monitor
Symptom: Dead.
Fix: Replace the following components on PS board:
IC201, IC202: AOP605 P/N Mosfet, Digikey 785-1140-5-ND
C200, CE101, CE105: 220uF 25V Cap, Digikey P5541-ND
CE102, CE103: 1000uF 25V Cap, Digikey P5544-ND
F200: 3A Pico Fuse, Digikey F2315-ND (modify to fit by bending leads and mount on backside)
Check the DC filter caps first.
If you are going to DIY and have proper tools and know safety precaution then please read on:
Most common failures in the LCD monitors are bad capacitors (bulging top/seal or leaking) in the power supply, blown fuses; poor solder joints, failed inverter circuits (blown fuse, shorted transistors, shorted/open transformers), bad lamps (poor solder connections or worn out lamps). You will need to open it up and inspect the inside, see example of failed monitors to get some ideas what to look for: http://s807.photobucket.com/home/budm/allalbums
Post back what you see inside so we can guide you further and it will help out other people in the future also.
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.badcaps.net
Capacitors kit: http://lcdalternatives.auctivacommerce.com/
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