TV goes black

I had the Same issue. on a 50PF9431D/37 set. Many Plasma Set's use a LJ44-00118A PS-505-PH Power supply from Samsung. Known to have this common problem. If you can, or have a friend that can Solder components?. Unplug your set remove the back panel & locate your power supply. It will be the PCB in the center of the set just above the Video/Audio connections. http://www.shopjimmy.com/power-supply-unit-lj44-00118a-from-philips-50mf231d-40.htm. Is a Link to a photo of the PCB. Make a note of the locations of all cable connections then unplug them all. Un-install PCB, Check all Fuse first. I believe their is 5 or 6 of them on the PCB. Then replace the two 3300uf 10v 105C Radial capacitors at C8060 & C8059. Look to see if the Caps are deformed and or split at the top. The location of the caps are in the Lower bottom edge of the PCB. A local shop may Carrie them if not, digi-key has them. Part # http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=493-1754-ND. Total cost was $7 with S/H.

The power and inverter boards are combined in this model. If you inspect the three transformers that power the lamps you will most likely see that one or more is deformed (looks like it is slightly melted). You will also notice that the board under the transformer is discolored due to heat. This board is also known for bad solder connections. The actual repair would be to replace the transformer (T1, T2, or T3) but as of writing this I have not found that part available without having to buy the complete board.