Without any knowledge of the mark of TV you have. If power is getting to the TV. ie check the plug wiring unless its a moulded plug. The likely cause which is repairable if you are competant, is that the power supply in the TV has failed. Common causes of this are the capapcitors used in the power supply. If you are able to do this then first remove the power from the mains and trace the cable to the area of power unit. You can check these capacitors visually. They should appear completely flat at the top. If any have curved tops then they are suspect. I would replace all the capacitors in that area as they are all likely to have failed to some extent. The are usually 105 deg C types available from places like Maplin. You need to be able to use a soldering iron exetra. Unless you have the skills take it to a repairer as high voltages are present. Do not take risks. Hope that helps.
John
hzplj9
July 2009