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Arfa Daily Arfa Daily is offline
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Default lcd monitor troubleshooting tips?


"Brandon D. Valentine" wrote in message
oups.com...
I've got a Dell LCD monitor that when plugged in and powered on will
show a beautiful picture for about 1 second and then goes immediately
dark. You can turn it off and back on and it will do the exact same
thing an infinite number of times. Same behavior with any computer
and with multiple video cables. It also behaves the same way without
a video signal attached. It will come on and show the self test
screen for a second, then goes dark. I hate to have to recycle the
thing when it clearly works, just something is preventing it from
staying on. I'm pretty handy with a multimeter and a soldering iron,
but I'm not sure where to start on this thing. Anybody fixed similar
issues with an LCD and have any suggestions on which component I might
want to investigate?

Thanks,

Brandon



Check that the actual screen is still producing an image after it has gone
'dark' by shining a strong light at the screen at a very acute angle. If it
is, chances are that the backlight has failed. This usually comprises a
couple of cold cathode flourescent tubes, and an inverter board to drive
them.

Inverters may or may not be readily repairable. If the inverter starts then
immediately stops, it may well be a cap problem, but it could also be a bad
tube that is 'overloading' it, and causing it to shut down to protect
itself.

Replacement inverters and backlight tubes available here. They can probably
supply something suitable.

http://www.lcdparts.net/ccfl.aspx

Arfa