green blinking light on front of tv

I'm new to the site, so if anyone could help me out, I have a problem with my sony TV(# kp53hs10 ) The light blinks 5 times and then the tv will blinkoff and then back on, with DTV formart:480p that comes across the screen. Does anyone known how to fix this problem??? I've tried unplugging the power cord and the cables. didn't work.What else can I try?

Thanks, auntspar