This indicates that the power board 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 fuse will be located on the board where the power cord connects. Replace with one of the same type and rating from your local Hardware store.
If the set still does not power on, I would say that there is a cold solder-joint, or a failed component (likely the capacitors) on the power supply board. The capacitors failing is the MOST common problem with these sets, especially after a storm or power outage. The caps themselves can be replaced for around $150 parts and labor.
If another board had an issue, then the TV's power light would be on or flashing.
Do you have any prior experience testing voltages on live circuits, or soldering?
If not then, locating the solder joint, or failed circuit could take several hours of a Technician's time, and would require someone that knows electronics on a circuit board level.
There is no button to push to make the set work again. It would definitely require component repair/replacement.
An estimated cost to replace the entire power board (worst case scenario), would be approximately $300 parts and labor.
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