I have audio but the screen is black on my television. I want to know if what you think the problem is, will be covered by my 5 yr extended warranty plan that I paid an extra $500 for less than 3 years ago. I have a 60" LG plasma tv.

1. Can you access the TV's menu? If so, have you tried the various Video inputs, and resolution rates 480p, 480i, 720p, and 1080i. Sometimes the set will be able to decode one resolution, and not the others.
2. Unplug the power to the TV and the cable box for 5 minutes.
3. Plug the power to the TV and the cable box back in, wait 2 minutes for the cable box to boot up and see if your picture returns.
4. Re-seat all the connections on your TV and your Cable box, as they can disconnect over time. If you still have no picture, there is likely an issue with the Plasma TV and a warranty repair will be required.
   

Ur tv buffer boards are dead,the X or Z is dead.Could be also both boards are dead too.Yes,this tv should be cover under ur extended warrenty,if it still under in effect,read ur contract years end date.