picture not lasting

[dwestwood]

LG 22inch LED TV Power on then picture for half a second then only sound Sometimes after hours off it as a picture for 7-10 minutes Once it stayed on 40mins If aerial taken out it displays no signal in different places on screen for hours Something stops the picture Timer is off

 

[hang-the-9]

Sounds like a system board issue, for a 22" TV you are likely just better replacing it with a working unit. A used one is very cheap, $50 maybe.