Hi


Thanks for using FixYa. From what you have described it seems the issue is with the power board or the main board we’ll need to check few things. When you open the unit up; take a look at the power board-the board where, the power cords/plugs goes into. You might see some filter capacitors a little bulged up in the top-If this is the case-this is your defective part(you can try to replace them-but some soldering equipment is needed). If not, then probably the main board has gone bad. This is the other board-where all the inputs are going into. Also check the Backlight Inverter Board if the sound is coming fine from the TV however as it’s shutting off so it should be either the power board or the main board. All this is only recommended if you have electrical expertise and know how to solder/re-solder components. Please do accept the solution if the issue is resolved or else revert for further assistance.


Thanks
Rylee