The make, model, age of the TV can matter. Long ago it was possible to burn out a VGA display by sending incorrect, unsupported video signals. For now, try the old unplug the set for about 10 minutes from power and all connections. Power on then see if the on screen display works. If not bad luck since most models are not user serviceable.
My TV wont turn on , but the standby light still work .
After I Have conected with my computer with VGA connector.
When i Have connected the connector i was heard buzzling sound and the tv start to switch all the general colors (red , blue ,green)
then I turned off and after that i cant turn on the tv , the standby light is on