[damen]

On most Samsung sets you can unplug the cable that runs between the main board and the power board to see if the backlights come on when the AC cord is plugged in. If the backlights come on this usually indicates the power board and the LEDs are okay and you have a mainboard issue or a bad screen. After reconnecting the power cable to the mainboard, disconnect the ribbon cable from the main board to the screen. If the set powers up with the ribbon cable disconnected, the screen is probably the problem. Sometimes if the set powers on with the ribbon cable disconnected, reconnecting the cable while the set is on will allow the picture to come on, sometimes for a moment or two.