# iBook G4 12" losing date and time



## jlyttle (Dec 18, 2005)

I guess that this model does not have a PRAM battery, this info is maintained by the main battery. My problem is this: after turning the machine on if hat has been off for a while, the date and tome revert back to 1970. The actual power of the battery is fine, it holds a charge and will operate the laptop for quite a while, so I don't understand how these settings are being lost or where to look to fix it. Everything else with the unit seems to be fine. Any help would be greatly apprciated.

-Justin


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## sinclair_tm (Dec 19, 2005)

all computers have a pram battery, just to store that info, even laptops.  or else it would lose the info when you switch your batteries around on a trip, and what a pain that would be.  so it sounds like you need to visit an apple repair place and have then get the pram batter replaced.


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## jlyttle (Dec 19, 2005)

Yeah that's what I thought too, but I found info in several places that warn that this model will lose date/time if you are slow in swapping batteries, you have maybe 15-20 seconds. So, the problem lies elsewhere.


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## mdnky (Dec 19, 2005)

You're right, iBooks don't have a PRAM battery.  You have about 20 seconds to switch batteries before you loose your settings.  On a side note, here's a list of batteries and their part numbers from the Apple Support site.

Try resetting your PRAM, if that doesn't work try resetting the PMU.


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## sinclair_tm (Dec 19, 2005)

wow, thats weird, so how long have they not been putting pram batteries in these things?


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## JoshT (Dec 19, 2005)

sinclair_tm said:
			
		

> wow, thats weird, so how long have they not been putting pram batteries in these things?




The iBooks have never had backup batteries.  All powerbooks starting with the titanium ones have had backup batteries but I dunno about anything before then.

For the original poster of this thread, if your battery holds a charge just fine but the date/time is still reset EVERY time you restart your computer then you have a corrupt PMU.  You can reset the PMU but you simply must be very careful.  If you do it wrong (or do it more than one time without starting up) then you will permanently corrupt the PMU and your software problem would turn into a hardware one that will cost you $$$.  Here are instructions for doing PMU reset:  http://docs.info.apple.com/article.html?artnum=14449

After you do the PMU reset and start up your computer the date/time will definitely be reset.  Normally that is how you'd know that you really did do a PMU reset correctly.  So just restart your computer as normal and if the date/time are still wrong then your PMU is corrupt beyond what resetting it can do.  You now either have to live with the issue (perhaps by turning on the option to set date/time with a time server) or take the computer to an AASP.


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## redghost (Feb 4, 2010)

I think there really is a PRAM battery, but it is soldered to the logic board.  I have been repairing a few iBooks recently and they all have little 5.0v button batteries on the logic.  This allows Apple to charge you an arm and a leg to resolve all the issues we used to be able to deal with by purchasing a little lithium battery.  Now for $500 you can let them swap in a new logic board.

I am having a narcolepsy issue with a G4 1.42 iBook that resets time to 1904 and will not remain awake.  All symptomatic of dead PRAM battery. No matter which of the three good batteries I use or which of the five chargers, the thing will not respond.  The theory that the rechargeable battery holds PRAM data only is not supported by the behavior of this iBook.  There is a logic board battery, but Apple tells you it is a capacitor.


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## and5150 (Sep 3, 2010)

Hi redghost,

I drilled my iBook to the LB, found the capacitor on the top side; but where should I look to find the LB battery?

thx,
Andrea


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## DeltaMac (Sep 3, 2010)

There's lots of misinformation in this thread.
The capacitor is the 'battery'
Batteries are a form of capacitor.
The iBook uses one that does not have long-term storage - only at most a few minutes when the main battery is out (or dead), and the power cord is disconnected. Usually, time and date dump immediately or you only get a few seconds.
From Redghost post - the default date for a 1.42 GHz iBook G4 will not be 1904, but will be 1970.
I have tested a few hundred iBooks over the last few months, all different generations of those. They will often behave very strangely, especially when stored with a dead battery, or the battery has been removed.

I have a successful resuscitation routine, if you are interested. It 'usually' will get any iBook going (if there are no other obvious problems), and assuming that the iBook has any response, and not just dead.


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## and5150 (Sep 6, 2010)

Thanks DeltaMac for the clarification!

My iBook doesn't seem to fall in the "video issue" cat, but more in the "totally dead" zone;
it showed the date reset to 1970 a few times before it finally died; I suppose multiple resets might have corrupted the PMU (??)...

I disassembled mine (a 12" G3/700 approx 2002, don't remember if I told), I'm now soldering a new cap;

I'll update if anything changes


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## and5150 (Sep 9, 2010)

BTW, as I read on other forums, sometimes iBook revives from this state... not my case;

current state is iBook completely took apart; despite specs googled around, the button-shaped super cap I desoldered isn't a 22&#956;F, but a 15 times bigger 0.33F.

In case you might want to know....

Andrea


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## and5150 (Sep 16, 2010)

cap wasn't guilty...
multiple PMU reset to make the old friend aware of the totally-empty battery, then tried to power up either with DC-power or fully charged battery, but to life sign 'til now

let you know,
Andrea


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## doramide7 (Sep 29, 2010)

sinclair_tm said:


> all computers have a pram battery, just to store that info, even laptops.  or else it would lose the info when you switch your batteries around on a trip, and what a pain that would be.  so it sounds like you need to visit an apple repair place and have then get the pram batter replaced.



Yeah that's what I thought too, but I found info in several places that warn that this model will lose date/time if you are slow in swapping batteries, you have maybe 15-20 seconds. So, the problem lies elsewhere.
__________________


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