Tv turns off by itself, three times in past two days, would come back on by itself now it went off and can't turn back on

The dam main board the tv Tuner signal board was dying and now it is dead.Tv now still have power light LED indication it is on just no picture wright?Yes.This tv the Tuner signal board is it dead.Can u do some basic mechanical work like take thing aparts and putting it back together again?Yes,tries websites like Shopjimmy.com,Ebay.com to buy a whole refurbish tv Tuner signal board for the replacement.Or the shops will cost u a little more than half of a new tv to service by them,because this tv,the main board it is dead,not serviceable only replaced that it.