Facing TV Problems? Ask a TV Technician.
Hi , I`m Jack , I will be helping you today
First thing to do here ;
Unplug the TV's power cord and hold the power button directly on the tv ,keep holding it for 20 secs or so then let the tv sit unplugged for a couple of minutes before you try it again.
You could unplug the cable box power cord as well during that time
Note that the cable box will take a couple of minutes to reboot