Sceptre TV 32in comes on fine after a few minutes the picture starts flashing

SOURCE: Power light flashing/ no picture

I have the same problem. The only way to get the TV to come on is to unplug it, but once you get it back on it turns itself off again in a few minutes.

SOURCE: RCA L32WD12 32in. HGTV LCD Television

I had the same problem happen this afternoon, so I took it apart, and the source of the problem is the key controller panel (behind the buttons). It's held in place by 2 screws, if you take the case apart, which is literally only 15 or 20 screws, and then loosen the 2 screws holding the key controller panel on, and then use a small screwdriver to space it out from the button caps. Tighten the screws, and put it back together. Just be careful not to let it go too far to the other side, or you'll have a problem with the menu going on and off at random, which is just as annoying.

SOURCE: TV Picture Goes Black

I had the same exact problem.
I removed the bulb and cleaned it. There is a small screen at the top of the bulb and it was covered with dust. Once it was cleaned I replaced the bulb and it solved the problem.
Thanks to those who posted the solutions

SOURCE: Screen Goes Green TV goes to stand by blinking 8 times

try adjusting your color tuners located inside tv behind speakers.

SOURCE: Sony KP-53HS10 AND "5" FLASHES at Timer/Stand by Indicator

i had the same problem someone told me to take the front cover off were the speakers are there the middle were you change the channels take them screws out and becareful there is electric stored up in there dont touch anything there is a square box with3 screws on top and three screws on bottom
turn your tv to video 1 and the first screw on top closes to middle turn it to your right a little at a time you will see bright colored lines then turn it to the left until they go a way then do the same with the other 2 on the top then shut off tv for 5 mins turn back on ahit the focus button it workd for me but be careful