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NastyComputers
Aug 22, 2010, 12:21 AM
Do iBooks have a PRAM battery? I have read somewhere before that they don't. Just would like some backup on this.



4JNA
Aug 22, 2010, 12:39 AM
Do iBooks have a PRAM battery? I have read somewhere before that they don't. Just would like some backup on this.


backup confirmed. there is no pram battery. there is a small capacitor that holds a limited charge for battery changes, but that's it.

remove the main/laptop battery for 10-15 minutes, and then upon restart you will need to set the date/time and everything else. best of luck.

MacHamster68
Aug 22, 2010, 04:03 AM
no it hasn't one, but a dying battery can cause the same symptoms as a dead pram battery as the little capacitor inside gets charged from the battery

NastyComputers
Aug 22, 2010, 05:39 PM
Very good that is what i thought. Its battery is shot to death, so that would be the problem. Thanks again

MacHamster68
Aug 22, 2010, 06:15 PM
the logic board mounted 0.022F 5.5V capacitor used to supply power to hold PRAM settings while changing the battery.
Unlike most PowerBooks and desktop Macs which have PRAM batteries and are capable of holding parameter RAM settings for extended periods, the iBook G3 & iBook G4 use a small capacitor which only provides around 20seconds of power which is considered sufficient to allow batteries to be switched without loosing settings. If this capacitor fails, settings will not be held and logic board behavior can become erratic. (from a website that sells them here in uk)

the big problem there is you can basically only check if the capacitor is working if the battery works

mine died not long ago but battery was just , just fine about 30min-1hr and suddenly one morning all dead , logic board looked like there had been a nuclear explosion inside , a known prob these failing logic boards on the ibooks ,usually they failed after the apple care period and apple did know that too like so often with their products,but i just like them so i look for another one

FourCandles
Aug 22, 2010, 06:23 PM
...
the iBook G3 & iBook G4 use a small capacitor which only provides around 20seconds of power which is considered sufficient to allow batteries to be switched without loosing settings. If this capacitor fails, settings will not be held and logic board behavior can become erratic.


Presumably if the charger is plugged in whilst changing batteries (obviously not always possible), this avoids the problem?

MacHamster68
Aug 22, 2010, 08:49 PM
i never did try that ,but as i understand it wont as the battery needs to be charged to get the capacitor charged:eek: