Power on but no picture

Question

Vizio 42 in LCD hooked up to cable and computer. 50% - 50% pip on and then the screen goes out. Power on no picture cable or computer. I unpluged and waited a while, little green power indicator will go on but no picture. I changed the battery in he remote and still no picture. I tried to turn it on from the side control buttons with no luck. We have had the unit for 2 years with no problem.