# intermittent blank screen on battery



## undrgnd (Jan 15, 2007)

my iBook's screen goes completely blank intermittently, but only when it is running on battery. The keyboard still works when the screen does this. There is no way to restore the screen image except to force a shutdown and then restart.

I verified my settings in energy saver under system preferences are correct and have not changed. my screen saver is disabled unless i manually activate it.

*Any suggestions on beginning troubleshooting?*

I have tried resetting the PMU, no change.

I have calibrated the battery about once a month.


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## sinclair_tm (Mar 11, 2005)

Are you sure that the iBook is still on when the screen goes blank? And why calibrate the battery so often? Two times a year is more than enough for that. It sounds like you may have a hardware failure of some kind, but you have already reset the PMU, which is what I'd be blaming. Do you have the CDs that came with this iBook when it was new?


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## undrgnd (Jan 15, 2007)

sinclair_tm said:


> Are you sure that the iBook is still on when the screen goes blank? And why calibrate the battery so often? Two times a year is more than enough for that. It sounds like you may have a hardware failure of some kind, but you have already reset the PMU, which is what I'd be blaming. Do you have the CDs that came with this iBook when it was new?


Sinclair - yes the iBook is still on. I calibrate the battery often to ensure I'm getting the most out of an old battery. The only CD's I have around are the Mac OS X CD's, but I could easily download drivers/etc and burn a CD if i had to.

Also: Today I found the screen blank and not fixing itself after a restart. It does not matter if it is using AC power or battery. 

Last night before it went out completely I could see the screen ok, and then when I grabbed the laptop near the edges by the mouspad the screen would move and squiggly lines were running horizontally across the screen. 

So would it be safe to assume I need a videocard or motherboard replacement or would it possibly be the display itself?


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## sinclair_tm (Mar 11, 2005)

Well, the video card is part of the motherboard on that laptop, so I'd say it's pretty much gone. You could look on ebay, and other sites that have iBook parts, and see if you can find a replacement, but I fear that you'll find it more cost effective to get a new Macbook. I asked about the CDs because one of the included CDs would of been a hardware test CD. You'd boot the iBook from it and run tests, and it'd hopefully tell you what is wrong.


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## shuuhen (Sep 4, 2004)

As I understand it, the screen now is _always_ blank (as if it were off) even when the computer is booting.

First thing I would've suspected would be the PMU, but there are a few other things I would try.

Have you tried resetting the PRAM? Hold the command (apple), option, p and r keys right after starting/restarting your Mac. Hold them until the Mac has restarted two or three times (you'll hear the chime after each one).


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