Prosonic PLTV-30 Won't come on

I have had the power supply checked out and that does not appear to be the problem. In standby, when you try to power on from remote or on-button on top, the screen flashes momentarily and the TV shuts down. I am so frustrated because they will not service it because I do not have an extended warranty. I paid $1500 for this TV and it only worked for 2.5 yrs. It's been sitting on my wall now doing nothing for almost another year.

The actual front of the TV says, SOVA and ShopNBC said that SOVA actually manufactures the inside of all LCD TVs. That's how they advertised it when I bought the thing. Now I'm really confused.