This indicates that the power board, in the TV, is not powering up at all. The quick fix is that it could be simply that the fuse is blown. To access the fuse, you will need to remove the screws on the rear of the TV and remove the entire rear panel. The fuses will be located on the board where the power cord connects. Please do not visually inspect these, but rather use a DMM (multi-meter) to test across the fuse for continuity. If one or more is found blown, then replace with one of the same type and rating from your local Hardware store.
If the new fuse does not cure the problem then, there is a failure on the power supply board inside the TV. Commonly the capacitors on this board will receive a surge and then fail. They can sometimes be visually verified by removing the rear of the set and inspecting them for bulges or leaking fluid at the top or the base of the caps. This is the most common mode of failure for these sets. The problem could also be a cracked solder joint, or failed IC regulator, in which case it would be more cost effective to replace the board itself. Average cost for this type of repair is going to be around $250 parts and labor.
Unfortunately there is no sequence of buttons or reset you can perform to get the set working again.
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