Chosen Solution

I’ve tried unplugging holding power button on TV for 30 secs then waiting a few mins to hit the power button. Still won’t turn on.

@chew1 since you have no standby light it is most likely a power board issue. Of course check toi make sure that you have power on your outlet.If you do, remove the back cover from your TV. Check the power board uses with a multimeter for continuity. Post some good pictures of your boards with your QUESTION. That way we can see what you see. Adding images to an existing question