Post originale di: jayeff ,
Hi It looks like more than one problem. Try the following: Disconnect the power from the TV, remove the back cover and then disconnect the cable that goes from the mainboard to the power board ''at the power board end.'' Reconnect the power to the TV. ''The screen backlights should all turn on full and stay on''. There will be no picture because the mainboard is disconnected. ''If they don’t all turn on'' or if the blink then you have a problem with the backlight LEDs or the connection to them. That may be one problem which needs to be sorted first. The next problem is with the lack of a picture. Also with the mainboard still disconnected from the power board, measure the voltages on the power board connector where the mainboard cable ''was'' connected to (now vacant). The voltage values should be printed on the board near the connector. '''Be safety aware''' ''if you do this as there'' ''is'' '''exposed lethal AC voltage''' ''on the power board near to where you’re testing. If you don’t know how to test safely when AC voltage is present then don’t do it! Remember to disconnect the power from the TV before touching anything in the back of the TV except if you are testing'' If the voltages are OK then the power board is OK and the problem may be in the tcon or the mainboard. Further testing would be required. If there is no audio either then more likely it is the mainboard.