Tv won’t turn on.

@paulmahone78300 good. You have power to the power board. Now for the rest, have you managed to measure the voltage outputs? You will need to find out if you have standby power. If yes, then your SMPS (power supply) is most likely okay. Now you need to measure the voltage signals from the main board to the power board.

Since your TV seems to be a bit off-brand, we really would need to see all of your boards. One board per picture well focused and large enough so that we can zoom in and try to identify your connectors and individual components. Also let us know the exact model number for your TV.

Remember that your power supply only does that, supplies power. It is the main board that tells your power board which circuit to turn on i.e. backlights, panel, audio and video circuits. It is the IR board that tells the main board to signal the power board for power :-) <simplified> Based on all of this my number one suspect with errors like this is usually the mainboard.

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