TV Display Problem
There are many reasons that a TV may power on but have no picture.
Backlighting burned out - In modern LCD TVs, the backlighting may be burned out. A technician can replace LEDs or CCFL backlighting strips.
Inverter is bad - It is possible that the inverter, which powers the backlights, has gone bad and needs to be replaced. It’s also possible that one or more capacitors on the inverter have gone bad, in which case a technician may be able to replace capacitors more cheaply than replacing the entire inverter.
Lamp burnout - In a projection TV or older LCD TV, no picture may be caused by lamp burnout. In this case, a technician can replace the bulb quickly and easily.
Picture Is Not Displaying Correctly
If the picture is displaying but there are problems such as vertical lines, a double picture, or a white display, this could indicate a faulty motherboard or mainboard.