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Received a Samsung TV from a friend said it did not work. The TV is black screen. Reading different forums I replaced the motherboard along with power board. Neither has worked. The power button has no light to it when in standby mode. When disconnecting motherboard to power board the back light does turn on. Any ideas what the issue can be?
@rsastuk “power button has no light to it” odd situation with a new power board. have you measured the voltages coming of the power board. Verify your model number please. I want to make sure it is a un49mu700 and not a 7000. Anyhow not much left to replace. Looks like the T-con board in integrated to the main board. Backlight comes on but no signal etc is commonly the main board but you said you replaced it (reliable supplier?) then the issue could be related to the button bar (check it to see if the buttons work) or the screen. Check your wiring etc. Post some good pictures of all of your boards and the interconnect wires so we can see what you see. Measure the voltages on the connector where the cable from the main board connects to the power board. Compare those with what is printed on the board. Let us know what those values are. Adding images to an existing question
