Television and Home Theater

I bought a mitsubishi wt-42311 television brand new in march 2003. In April 2005 we went to turn it on and the green light on the front would come on it would click and then turn off. No picture or sound. Brought it to a service center and they suppossedly put what they called a power control module in it. Around $600 for the part I believe. That lasted until July of 2007. Did the exact same thing. I had the same repair done again. After this I decided to sell the television why I still could. Sold it two weeks ago and  it lasted one day.

 Hello, I have a 50" Mitsubishi TV that I purchased new in Nov. 1998,  as we were watching it one evening, awhile ago, it simply "clicked" and went off. Now when you hit the power button to turn it on, it clicks and the green power indicator light comes on like all is well (for about 5 seconds) and it "clicks" off again. I didnt want to throw it out before researching a cost to repair first,  because it is in great shape appearance wise. Any helpful advice will be appreciated, Thanks in advance!! SlickRick50

tv will not turn ran diagnostic showed code 21 what could be the cause of this problemand how can it b repaired