JVC LT 32E479 UNABLE TO SWITCH ANY CHANNELS

get a set top box converter on amazon

have a look at your manual troubleshoting Here

So you can assume the issue is with the channel NOT the tv.

I would either call JVC to see if known issue or to inquire if set has a lockout feature that kills remote and all button features----other possible reason in main board with all micro functions has a problem.

Deffective power supply section.

The solution posted here worked perfectly for me.
http://www.avforums.com/threads/cannot-change-channel-on-samsung-le26r74bd.839670/

What service company do you have for your TV? Is it dish network or direct tv etc. You can do a channel scan once you verify the service company. A cable service provider will only provide 99 channel to scan/sort while a satellite service provider will provide you more channels to sort/scan.

On the right hand side of this television there are panel buttons. It appears that your son in law knocked the tv out of the correct input. Press the input button in order to cycle through the 5 inputs. Typically pressing the input button on the side panel of a television and pressing it again and again and again will make it change inputs. Universally the buttons on the tv panel function as follows: Channel up moves the cursor up. Channel down moves the cursor down. Volume + moves the cursor right. Volume - moves the cursor left.
Hope this helps

Seeing as it does not have a digital tuner in it, I would think this would be the problem, you will have to get a box for it.

i have taken the tv to repair shop a circut board has went on it