When we can't find online manuals or tips we get it serviced.
If it was the backlight you should see the image if you shine a flashlight onto the LCD.
My samsung 52 inch tv will turn on , the picture flashes for 1-2 secs then goes black. There is sound but no picture. The five 1000 mfd caps were previously replaced and look good. How do i check the backlight inverter boards? There are four of those things>> Anyone????