ViewSonic monitor spasm

[les]

I have the model VG800 LCD and have looked for the schematic online, but
have not found it yet.
However, here is the problem.
When I power it up, the green light lites, then an image flashes for a half
second
then disappears. The light remains on. It can be reset, and the process
repeats itself.
I tested the external power supply with a 5 amp load, and it manitains 12
volts.
So I assume there must be a logic switch internally that trips off.
Can anyone familiar with this model give me more specific ideas?
Thank you.

Les

 

[D Yuniskis]

les wrote:

I have the model VG800 LCD and have looked for the schematic online, but
have not found it yet.
However, here is the problem.
When I power it up, the green light lites, then an image flashes for a half
second
then disappears. The light remains on. It can be reset, and the process
repeats itself.
I tested the external power supply with a 5 amp load, and it manitains 12
volts.
So I assume there must be a logic switch internally that trips off.
Can anyone familiar with this model give me more specific ideas?

Most likely* bad caps or decoupling in the supply to the
(backlight) inverter. Viewsonic's are plagued with
this problem.

*YMMV

 

[SolarAngel]

responding to
http://www.electrondepot.com/repair/viewsonic-monitor-spasm-21580-.htm ,
SolarAngel wrote:

idea wrote:



I have the model VG800 LCD and have looked for the schematic online,
but
have not found it yet.
However, here is the problem.
When I power it up, the green light lites, then an image flashes for a
half
second
then disappears. The light remains on. It can be reset, and the process
repeats itself.
I tested the external power supply with a 5 amp load, and it manitains
12
volts.
So I assume there must be a logic switch internally that trips off.
Can anyone familiar with this model give me more specific ideas?
Thank you.

Les

--

have similar problem only thing is that monitor shows screen after several
minutes.
by any chance do you remember what was the issue with this monitor

thanks.