I'm sorry to say this is most likely some type of failure that will require parts and service but to be sure please try this:
-unplug the tv POWER cord from the wall outlet.
-press and hold the power button on the tv (not remote) for 20 seconds and release.
-plug in the tv power cord and try to turn on.
If that does not help then unfortunately there is not going to be any easy reset/fix. The tv needs diagnosis, parts, and service.
As a technician, theoretically I could help you with that but if you do not have the needed skills and tools then I would not recommend you repair a tv of this size and age due to the high cost of parts/labor and probability of more internal failures. But at least you saved a lot of money by coming here first- typically repair shops charge $99 up front just for diagnosis (to hand you an estimate).
Despite the bad news, I hope you appreciate the answer that I provided so far. If you need more help or don't understand something use the REPLY option.
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