Friend measure if voltage is coming to the standby on the remote control sensor ... at the voltage input check the protections low surface resistance .... check the selector open the shield to see if it is not internally burned or can isolate it say take it out to see if the tv responds to a damaged selector can block the ignition ... also check if any integrated is heated a lot which would indicate a short circuit in the circuit or around it ... check the HDMI wiring circuit lines of the hdmi ports are going to give a circuit check it .... if I found the short circuit in some integrated micro just make sure that the short does not come from any smd capacitor if it is the integrated circuit that entered shortly change the main ...