Samsung 204T syncmaster problem -- not bad caps

I've got one of these that comes on and then the display fades out to black after about 20-30 seconds. Turn off then on and same thing. When opened up, I can see the CCFLs are brightly lit although the display has faded to black. I replaced the power supply caps even though they were not bulging so I don't have to deal with it later on. I swapped in a converter board (the one with video inputs) and no joy. I opened up the column driver board and blasted it with cold spray. I blasted all boards with cold spray to see if the fade rate changed..... still no joy. I've googled and bad caps seems to be the prevalent problem, I am not using the DVI connector as I know there is a data rate problem with the display blanking out..... Any clues or ideas for whatever it is that I missed??

Thanks a bunch ;)

al

Reply to
mickgeyver
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Sorry for my english and my low preparation, but u have checked the voltages on psu output, before and after the blak screen? So u can find which board is the problem, it sounds to me like a problem with the supply of the converter bd or mostly the lcd panel, find the lcd conn. pinout and check if before and after the blackout there is the tipical voltage (5v..?) Bye.

Reply to
Dav.p.

ges on psu output,

m, it sounds to me

l, find the lcd conn.

ltage (5v..?)

I'm getting a good clean 13v from the power board and the regulators on the converter board measure good as well. 5v, 3.3v, 2.5v. The power good signal from the LM393 on board is in the correct state. I'm now focusing on the column driver driver board as I seem to recall that LCDs in general require +/- volts to make the pixels go on and off. There is some regulator circuitry up there I've yet to explore.

al

Reply to
mickgeyver

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