<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">The screen on my Powerbook G4 has gone black. The laptop boots up (I can hear it) but the screen cannot be seen unless a bright light is on in the room and then it is still extremely dark.<div><br></div><div>This happened out of the blue last night on the way home from a trip. It worked fine yesterday morning prior to leaving the hotel. During the drive home I took it out of its case to play some games during the 5 hour car trip and I couldn't see anything at all. We were driving after dark.</div><div><br></div><div>When I returned home I found I could vaguely see the screen if I was in a brightly-lit room. I have gone to display and the brightness is turned all the way up. It seems to make no difference if I slide the control all the way down or all the way up. The monitor light keys have no effect either.</div><div><br></div><div>I found the following information at applefritter.com but I am afraid to do ANYTHING until I hear from this board.</div><div><br></div><div><div>Powerbook G4 screen goes black randomly...</div><div>Submitted by bigd on March 9, 2007 - 3:08am. Hardware Repair Help</div><div><br></div><div><i>I have a 12" Powerbook G4 1.5" and lately the screen randomly turns itself off, the whole thing goes black, like it was asleep or off, but the computer keeps running just fine. The computer itself stays running. What I've been doing is putting the computer to sleep by closing the lid, letting it rest for a few seconds and turning it back on by opening it.</i></div><div><i><br></i></div><div><i>I can still see that the screen is on, but the display is dark. It randomly does it. I switched the power settings to "never" for sleep and like 5 minutes for display sleep. That worked as long as its plugged into the AC adapter. When I unplugged it it did the same thing. I closed the lid and then it went to sleep and then I opened it and switched the battery settings to the above, and it was fine.</i></div><div><i><br></i></div><div><i>I set the PMU and NVRAM again. So far it's not doing it but I am worried that it's a backlight issue or something else? I have heard of random sleeping problems with the powerbooks, but mine doesn't actually go to sleep. Any insight would be great. Thanks!</i></div><div><i><br></i></div><div><i>bigd</i></div><div><i><br></i></div><div><i><br></i></div><div><i>that's more of a power manager thing</i></div><div><i>Submitted by coius on March 9, 2007 - 3:19am.</i></div><div><i><br></i></div><div><i>the power manager controls sleep as well as the brightness of the display. Sadly, i never found out what the solution was on my old iBook before I sent it in to get it replaced by my current G4 iBook (i had the 900Mhz G3, They gave me a 1.2Ghz iBook after my G3 went in 14x Undecided ) anyways, it sounds like the power manager is having problems.</i></div><div><i><br></i></div><div><i>I would say if it looks like it's still doing, what you do, is unplug the machine, pull the battery (save your data first before shutdown!) and press the CUDA switch (probably under the keyboard if it has one or something) and reset it is fully. If you have time, and can wait, let the system sit for 24hrs w/o power whatsoever.</i></div><div><i>It might be that the power manager did not fully reset itself if the LCD Backlight goes off again in the future.</i></div><div><i><br></i></div><div><i>if it still has warranty, and it continues to do it, call apple and let them know, it might be a hardware problem (most likely not, Apple just would rather replace mine that have me send it in for the 15th time)</i></div><div><i><br></i></div><div><i>Anyway, Good Luck!</i></div><div><i>Coius</i></div><div><br></div><div><br></div><div>HELP! </div><div><br></div><div>Victoria Bush</div><div><br></div><div><br></div></div><div><br></div><div><br></div></body></html>