PowerBook G4 Blank screen

Hi folks just opened pb this morning and the screen came on but then it went black and now I can't see anything on the screen.
It is 1.67ghz 17" could any one advise a possible cure as I don't fancy going out spending £1k that I havnt got !!!!
Thanks in advance
Nelo

just an update if i look closely i can see pictures and volume controls work so i think the pb is working just there is no light in the lcd scren

if any one has had the same problem please advise what actions i might take to repair the PB as i am quite fond of it

thanks in advance
nelo

It sounds like the backlight is not working. That could be from failure of the light itself or a bad inverter. The inverter is rather easy to change, however, the backlight on most LCD screens is difficult to get at. Apple recommends replacing the entire screen assembly.