I've had a couple TVs go on the fritz that power cycling would not resolve, yet another easy fix did the trick. I simply unplugged the TV, waited a while, the plugged it back in and powered up the TVs. Good as new. There was at least 17 year gap between the instances I've mentioned with my own TVs, but I've known this to happen many times on LCD monitors at work, where power cycling help, but unplugging temporarily brought video back to life.
I'm happy to say my 10 year old Sony W4100 HDTV is still working like new, although I did have to do the unplug trick once in all those years (it was actually just a few months ago, but I can't remember the symptoms now, just the fix) I was worried briefly.