hittade det här efter visst letande:
I'd like to share a recent experience with my iBook (white, dual USB, 600mHz). I hadn't used it in a few weeks and when I turned it on, the battery was completely dead. I booted up the machine and was very surprised to find that the battery wasn't even recognized. There was a little "X" over the battery icon in the menubar (OS X 10.2). I attempted to re-seat the battery, zap PRAM (using the key combo upon startup), and reset the Power Manager. Nothing worked. So I called tech support and they had me do all of those things over again. Finally they agreed to send me a new battery.
In the meantime, I decided to try one other thing (after reading about iBook battery issues somewhere online). I booted into Open Firmware and typed "reset-nvram", followed by "reset-all". Surprise, surprise...my battery came back to life and recharged fine. Too bad Apple tech support didn't tell me to try this!
Undrar om det kan funka på en Macbook?
Och hur kommer man in i Open firmware i starten?