Hi @zperazzo ,
Does it do this when looking at the TV menu screens?
Can you try another signal input type e.g. a dvd player to see if it occurs to eliminate the signal source from the equation?
If it still happens regardless of the signal input device or input type then when the screen goes black (for long enough) try shining a torch at an angle close to the screen to check if there are still images being displayed. They will be very faint if they are there so trying this in a darkened room may help to see them
If so then there is a screen backlight problem.
This could be caused by faulty backlights, faulty power supply to the backlights or even the mainboard turning off the backlights for some reason when it shouldn’t.
There’s not much information out there for Sharp TV so initially all you can do is to disconnect the power from the TV and remove the back cover and check that all the cable connections between the boards are OK and the LED power cable between the power board (or maybe the mainboard I’m not sure) and the screen is OK at the power board (or mainboard) end anyway.
Next check on the power board for any obvious component damage e.g. blown or leaking capacitors or heat stressed components etc .
If everything looks OK then voltage measurement would need to to made on the power board to check if it was working OK etc. As I said not much information out there so I don’t know what the voltages should be, although you could measure the LED power voltage when the screen is working and when it’s not I suppose to get some idea.
If you decide to try this then be safety aware as there is exposed lethal AC power on the power board when the power is connected. If you don’t know how to test safely when AC power is present then don’t do it! Contact a reputable, professional TV repair service and ask for a quote
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