Led two time blinks not on

@gurdeepsidhu could be a power board or main board error. Remove the back cover and visually inspect the boards for any damaged components etc. Also, check the ribbon cables to make sure those are properly seated and do not show any burn marks etc. Then get a multimeter and check the power board. Use this LG 49SJ810V No Power flowchart to see where you need to check the voltages on your power board. Let us know what voltages you get on that.

Take some well focused pictures of your boards and post those with your question. That way we can see what you see. Adding images to an existing question