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LCD Screen backlight problem

I have an Acer AL 1521 LCD screen. I have bought a newer power supply but after a few minutes the screen goes black. I can see that there is writing on the screen but it is too dark. I suspect that my backlight might be packing up. Any suggestions?

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Re: LCD Screen backlight problem

Sounds like an inverter problem. If the power supply is internal replace the capacitors coming out of the voltage regulators. These are usually 1000mf and/or 470mf. If that doesn't do the trick look up the numbers on the 8-pin chips that drive the secondary transformers on the inverter to see if they are getting the right voltages.
Good Luck!

Posted on Feb 20, 2008

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If this helps, please rate my solution. Have a great day.

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Monitor going black after a few seconds can be causd by a faulty power supply or inverter. Some monitors have both as one unit.
Sometimes it is basic failed capacitors, After that then I would look at transistors.
The average monitor from 17 to 20 and sometimes the 22s have usually 4 bulbs in them. One bad bulb will also cause the inverter to not fire up.
Bad bulbs usually show pinkish tint, or flickering or are dark at center top or bottom of the display.
ebays bammbammfran

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