screen goes blank intermittently on battery

[undrgnd]

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 - article)

I have calibrated the battery about once a month - article

 

[OrangeSVTguy]

the ibooks are notorious for their video card/mother board going bad. sounds like yours might be going out...

 

[undrgnd]

things have changed for the worse

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?

 

[OrangeSVTguy]

here's a guide to fix it if you want to do it yourself.
http://geektechnique.org/projectlab/726/diy-obsolete-ibook-logic-board-repair

there is another cure by putting a shim underneath in between the video card and the bottom case.