My Toshiba 42" inch LCD won't turn on. The green light comes on for a about 10 seconds and then it turns off all by itself.

seems like capacitor problem, chack them and if thay have exploded replace them.

flat panel won,t turn on

you lcd tv not setup problem. that" s main board gone in. you need a tachnician for it.

If you keep getting this problem(green light turn on for 5 to 10 seconds then TV shuts down along) you get to try this:
On ebay seach, type in "40E210U dead" there is one solution, good luck!

FIRST GREEN LIGHT WOULD COME ON. TOOK IT AWHILE BUT ITWOULD FINALLY TURN ON...NO NOTHING. IT'S GETTING SPARK CAUSE WHEN I PLUG AND UNPLUG IT AT THE SOURCE OF ENERGY IT SPARKS. FUSE IS NOT BLOWN

3 blinks indicates lamp door is not on or has not been reinstalled properly. This also could mean the lamp door switch has failed itself. Try removing the lamp door and putting back on, if that doesnt correct the problem then I recommend having the switch replaced.

solution
step 1: At first test your fly back Transformer
step 2 : Test the tube back side bulb and video I.C.

We have a 42" Model XV42L HDTV10A 100-240V,2.5A,50/60HZ....when we turn the TV on the screen is flickering and then shuts itself off....sometimes it will come on for a few seconds and then shuts off

Need s to be replaced the main board.