
Here you go:
Turn your TV on, and hope that it will shut itself off (or wait for the next time it shut itself off). Once it is off, immediately try to turn it back on. It won't, but you can look at the LED indicators panel. If you see "stand-by" AND "lamp" blinking, then proceed to try out this fix. Otherwise, you have a different problem than mine.
Now, remove the lamp cover at the back. You will see a switch at the left side (red circle in the picture). Unplug the white/blue cable from the switch. Put a jumper across pin 1 and pin 3. I used a paper clip. Then tape the end of the cable to make sure no wire is exposed. Now your TV will think that the lamp cover is always closed regardless of what the truth is. Put the lamp cover back on and enjoy watching TV again.
This issue is consistent with what I thought earlier: something is not making a good contact, and this is more pronounce when weather is cold. The two blinking LED means the lamp cover is not closed properly. That leads me to think the switch might be the problem. This jumper trick by-passed the switch, and my TV has been behaving well since then. If you used this trick, just remember to shut off the TV before removing the lamp cover ever.