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!
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Sounds like a backlight problem to me. If you input a signal to the HDMI or Composite input and then it goes black have you tried taking a flashlight to the screen to see if the picture is still there but just dark? That would indicate a backlight issue. That model appears to be an LED edge lit backlight, so if the picture is still there after going black your going to have to trace out the backlight circuit and see whats going on. Usually with LED backlighting if it comes on at all then the LED's are good, its just the driver supply thats failing to keep them on. Some TV's have a small separate board that provides the backlight control, but i suspect with this model its on the power supply board and not the motherboard. Have you checked that board? It could be bad caps on the power supply board, check the voltages to the backlighting when it lights up and then when it goes dark. It could just be some failed capacitors on the power supply causing that voltage rail to drop off.
Hello.The screen goes black means that the backlights of your LCD is not working.Maybe the problem is the power supply or the driver board of the backlights.They shutdown because there have a shorted parts on the circuit or power supply.
Did you try to reset the power and turned on and get a picture or every time that you reset the power it will get a picture and the picture goes black?
Try attaching an external monitor to the laptop & see if you could get any display on it. If this is successful, then you might have either a faulty LCD cable or screen inverter board. The
LCD cable transfers data signal from the motherboard & video card
to the LCD screen. It also supplies high voltage DC power to the screen
inverter board. The screen inverter board works as a power supply for
the backlight lamp mounted inside the LCD screen. It converts low
voltage DC power to high voltage AC power needed for the backlight lamp.
Ur tv now power on only have picture few mins,than dead,have sound only?Yes,than the 1 or 2 the long board call the LCD inverter boards are dead.The LCD inverter long boards help the LCD screen to have a backlight to produced a picture.Tries websites like Shopjimmy.com,Ebay.com to buy 1 or 2 long LCD inverter boards for the replacement.
Its probably not the backlight but the LCD inverter. Just replaced one on my Acer and all is well. Bought it off of E-bay for under $10. Its a cheap and easy fix if it is actually the problem. Good luck, Todd
More often then not, this is attributed to a failing Backlight Inverter. A Backlight Inverter, is a power board mounted below the screen that actually send power to the Lamp inside the LCD itself. Check to see, when it goes out if there isn't still some images faint in the screen. If this is the case take it to a local repair shop and have them order one and replace it. repair cost for this shuold be around 65-100 dollars.
If this helps, please rate my solution. Have a great day.
ICheck the power supply connections make shure tht the plugs are seated correctly. The power supply isreplaceable as a complete uitand you have to return a repairable unit.
Sorry to have to tell you this, but this is common in LCD monitors. The reason that it is going black when it boots is for one of two reasons. You either have a bad power supply that powers your LCD or your LCD's backlight is blown. These can be repaired or you can purchase a new one. But if it goes black 9 times out of 10 is because the backlight is bad. These can be repaired!