please complete the following at least one time:
-disconnect ALL audio/video cables from tv.
-unplug the tv power cord from the wall.
-press and hold the power button on the tv for 20 seconds and release button.
-plug in the tv power cord only and try to power on.
-test if you can use the volume, menu, etc buttons on the tv. If you can, go ahead and re-connect the audio/video cables the tv and then use the INPUT button on the Sanyo remote to get back to HDMI where the xfinity is plugged in.
If the problem continues then unfortunately there is not going to be any easy reset/fix. The Tv has an internal failure and the back panel needs to come off, then parts ordered and installed. In this case likely the Main board in the tv. If that is something you want to attempt then reply back here and I can help you (a meter and some previous electronics experience is required). If you are unable or unwilling to perform these operations then a repair shop should be consulted.
I am here to help you. Please reply back if you need clarification on any of the above, or even if you just want to say "thank you" :-)
In keeping with the design of this website, please be sure to click the 5 STARS or SMILEYS rating now. Doing so does NOT close the question or prevent us from continuing our conversation here. My livelihood truly does depend on your positive rating.
I understand news of a failure is upsetting but clicking the "bad/poor" rating does NOT do anything to fix your issue, nor does it issue you a refund.