I Have A Phillips 55" Rear Projection Tv. Model 55pw9363. The Screen Went Black. Do I Need A Power Supply? I Took Rear Cover Off And There Are Three Separate Tubes About 4" Long And I Think There Suppose To Be Lit And There Not.

Those tubes are the color guns and they would be lit when tv is on. There is a diode in the power supply that may have went. Be careful because you will need to discharge the power supply before attempting any repair. There is a lot of built up voltage.