I have a Philips 47PFL5422D/37B TV that recently developed a problem. My wife was watching it and after about 5 minutes of being on, it shut itself off. Then it would come on only to shut itself off again after 3 or 4 minutes. This happened several times, and now it won't come on at all. The green power light flickers very lightly and there is a high pitched siren type squeal coming from back of set. It appears to be coming from the upper third at about the middle of the set. In my experience from many years ago, this squeal was most likely a fly-back transformer, but I doubt this LCD TV has one of those. Any advice would be greatly appreciated.

Bill