SOURCE: 42 plasma philips
I had a similar problem. You likely have 1 or more bad capacitors on the power supply board. You can easily identify them - they have a raised or rounded appearance on the top instead of being flat. Remove the power supply board and take to electronics repair shop and have them replaced. The capacitors only cost me $4.24 for two. Now mine works fine. The repair man replaced them for free. It took him only 10 minutes to solder them on the board. Easy, cheap fix but manufacturer won't tell you that. I fixed this on 1-02-09. My 2 bad capacitors were "3300uf 10v" and I replaced with "3300uf 16v" but you might be able to replace with "4700uf 35 v" also.
yes, by canging the bulb. it proboly went out while the television was already dead. you can try but i would hire a proffesional. it may cost 100$ or more.
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