In order to install the update, you have to plug in your power adapter.
Read this compendious article about the Battery Update 1.2...
Macbook Pro 15.4' Mac OS X (10.4.8) Core 2 Duo 2.16 GHz
Have just had exactlyy the same experience. Battery discharges to around 40% and then power just goes off. No warning, no nothing. Just powers off. Useless.
Have tried re-setting PRAM (ii) re-setting SCM (iii) calibrated battery.
Useless. Now can't afford to try running without power connected, otherwise will get caught in an unscheduled re-start during some file writing.
Is there a way to reverting the software to its original state?<</div>
Yes. Archive and install. Or erase and install if you have complete backups made.
Reinstalling Mac OS X (archive and install):
Calibrating MacBook Pro batteries...
PowerBook G4 (15-inch Double-Layer SD), MacBook (all models), MacBook Pro (all models), and MacBook Pro (17-inch) (all models)
The battery calibration for the PowerBook G4 (15-inch Double-Layer SD) and any model of MacBook or MacBook Pro has been updated because of a new battery released with this computer. With these computers, follow these steps to calibrate your battery:
Plug in the power adapter and fully charge your PowerBook's battery until the light ring or LED on the power adapter plug changes to green and the onscreen meter in the menu bar indicates that the battery is fully charged.
Allow the battery to rest in the fully charged state for at least two hours. You may use your computer during this time as long as the adapter is plugged in.
Disconnect the power adapter with the computer still on and start running the computer off battery power. You may use your computer during this time. When your battery gets low, you will see the low battery warning dialog on the screen.
Continue to keep your computer on until it goes to sleep. Save all your work and close all applications when the battery gets very low, before the computer goes to sleep.
Turn off the computer or allow it to sleep for five hours or more.
Connect the power adapter and leave it connected until the battery is fully charged again.
Tip: When the battery reaches "empty", the computer is forced into sleep mode. The battery actually keeps back a reserve beyond "empty", to maintain the computer in sleep for a period of time. Once the battery is truly exhausted, the computer is forced to shut down. At this point, with the safe sleep function introduced in the PowerBook G4 (15-inch Double-Layer SD) computers, the computer's memory contents have been saved to the hard drive. When power is restored, the computer returns itself to its pre-sleep state using the safe sleep image on the hard drive.
My problem is that computer shuts down without any warning at around 15-20 minutes battery charge left. Before battery update, I would get a warning about low battery at 9 minutes of battery power left, and it would go to "Sleep" mode at 2 minutes of power left.
I've tried leaving it off for few hours, battery calibration and all, but without results.
I am gonna be in London in a week or so, might take it to a Genius bar.
Just contact Apple and have the battery replaced. Mine's also acted funny, shutting down at times when it showed lots of time left, 20%, then plugging in and showing no time left 0%.
Got my new battery today, under warranty. Will see what happens when getting down to the low levels of battery power.
This is now my 3rd battery, both the older ones gave me good battery life, 1st one was replaced under recall, ± 150 cycles, 2nd one after battery update 1.2, 169 cycles.
I'm not complaining, MBP is 16 months and I have a brand new battery...
I have the same exact problem and I thought my battery was a defective one, but it's not! I have checked its serial number and I can't have it replaced. Despite this, my mbp still shuts down unexpectedly while still having 80% of its charge left... What can I do?
Something is wrong with this battery update. Mine worked all right before being updated.
Is there any way of 'downgrading' the battery? By re-installing the previous firmware, for instance?
MacBook Pro 2.16 Ghz Core Duo Mac OS X (10.4.9)