LG Tv has sound but no picture

My LG 47LS4500 TV is automatically turning off after 5-10sec but the sound stays on until I turn the tv off. Is there anyway to fix this? I’ve unplugged and plugged everything back in and I’ve put new batteries in all of the controllers even the ones I don’t use can anybody tell me what else I can do because I’m about to throw this in the garbage please let me know what else I can do soon because I really don’t want to throw this away thank you.