I've got Powerbook G4 12", that works normally with the external screen - but inner screen shows nothing. Inner screen is checked - and fully working. Powerbook starts, chimes, then screen flickers a bit - but stays black. I though, that it's hall effect sensor - but I checked it, DC-DC Board - everything works fine.
Suddenly I checked system properties - and found out, that it thinks that notebook is closed.
I already compared this logic board with working one - but found nothing. What is needed to be checked first?
P.S. I forgot to say, that inner keyboard worked fine, but is not working anymore - with screen at once.
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