I did the cleaning bit and to no avail. I have the same simptoms. I think it has to be in the inverter or lcd screen. most often when the screen goes off i can see a faint screen when I do a Fn F3 it will go out. so the light seems to be what is going out. I pluged in a monitor and everything works ...

I have a T42p that worked fine until a few days ago when it started to give me a box with "Please Wait" Preparing to turn off the monitor. Then it turns off the monitor. Now it will only stay on a few seconds to a couple minuets. Is there a fix?