600E display problem

[prenj]

I have a Thinkpad 600E.
Couple of seconds after power-on picture disappears from display.
After Fn-F7 is pressed, it works again for couple of seconds and then picture dissapears again.
When external display is connected, the picture on it is OK.

[whizkid]

Sounds like the display inverter is failing.

When the display is dark, try shining a light on it from the top of the display. If you can see it, then your backlight is off, either because the intervter is off or because the CCFL tube is failing or has failed.

Replacing the inverter is a cake walk. Replacing the CCFL is tricky, but there's a thread on that very topic.