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A new way to resuscitate a dead battery System
In my most recent issue of the MacWorld Weekly e-mail newsletter, they reposted a hint that I hadn't yet seen on Mac OS X Hints. So this is a repost of a repost. :-)

They reported that on the Laptop Batteries special report on MacInTouch, reader Rob Wyatt reported that after trying and failing in everything he could to resuscitate his dead battery (reseating the battery, zapping the PRAM, resetting the Power Manager), he finally found a magic bullet. He booted the iBook into Open Firmware by pressing Cmd-Opt-O-F at startup. He then typed reset-nvram, hit the Return key, and then typed reset-all.

When his laptop restarted, the "battery was recognized and recognized and recharged perfectly. Subsequent readers confirmed that the technique revived batteries they too had given up for dead."

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A new way to resuscitate a dead battery
Authored by: XiMac on Jul 21, '03 11:01:13AM

If I'm not very, very wrong, this trick reset the open firmware to the original-on-factory OF. Be aware that the PowerBook users that needs an OF update to run OSX must update again the Open Firmware before restart on OSX.

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A new way to resuscitate a dead battery
Authored by: chabig on Jul 21, '03 11:55:23AM

This doesn't revert the machine to old firmware (how could it?) It just resets the values to their default settings.

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A new way to resuscitate a dead battery
Authored by: johnsawyercjs on Sep 26, '03 03:41:16AM

No, resetting a Mac's "Open Firmware" does not reset the Mac's "firmware" chip. This is an unfortunate case where two different things have similar names. The firmware chip that gets updated by Apple's firmware updaters, is a different chip than the one where the Open Firmware settings are stored. After you do an Open Firmware reset, you don't have to re-apply the latest firmware update to maintain OS X compatibility.

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A new way to resuscitate a dead battery
Authored by: firthy374 on Jul 21, '03 11:11:04AM
In addition, the "set-defaults" command should come between these two as follows:

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A new way to resuscitate a dead battery
Authored by: airdrummer on Jul 21, '03 01:04:09PM

well, my 4mo.old battery tech clamshell battery was starting to lose capacity (would only charge to 90%, 88%, etc) so i reset the pmu per apple's instructions, did the OF resets (minus the set-defaults) and the ibook refused to charge the battery(green, no amber)-: swapped in the original apple battery(which only holds 1/6 of its original charge, ~30mins) and it charges fine...

so what killed my bti battery?

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A new way to resuscitate a dead battery
Authored by: palbax on Aug 18, '03 01:19:38PM

I am a wallstreet 250 owner with openfirmware 2.01.
reset-nvram is not a known command.
What am I doing wrong?

My battery is still dead after all the reset and insert-extract procedures.
Is it really dead?
Many thanks

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A new way to resuscitate a dead battery
Authored by: macsolve on Aug 23, '03 05:34:02AM

I just tried this on a dual USB iBook of newer model (out of warranty by 5 days) with a battery that wouldn't take charge. The iBook would die immediately when pulling the power cord. Resetting PMU would not help.

This cure worked perfectly.

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A new way to resuscitate a dead battery
Authored by: minicop on Feb 07, '12 05:19:25PM

It worked for me too!!! Thank you very much!

I have the same ibook G3 model. It was a gift from a man who didn't know what to do with it. Now is like new. I'm using it with OS X 10.4. Yes, slow response but enough for read or listening itunes.

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A new way to resuscitate a dead battery
Authored by: mnystedt on Jul 21, '03 01:12:53PM

My PB G4 12inch was totally freezing up (mouse would not move, could not force quit) now and again without any apparent pattern to it. I had taken out the 512Mb expansion RAM and it was still freezing up. The only thing I could do was hold down the power button until it rebooted. I was on the phone with Apple Support and they told me to try these exact things, without any effect. Finally they told me I had bad RAM and it is now sent in for repairs.

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A new way to resuscitate a dead battery
Authored by: hungry_worm on Oct 01, '03 04:55:47AM

A reply to mnystedt on Mon, Jul 21 '03 at 01:12PM whos powerbook froze....

I had nearly the same thing with my iBook Dual USB, in my case it would freeze as soon as the powerplug was pulled, rendering it a non-portable laptop. Very tearful annoying.
I reset and zapped whatever was possible but nothing worked. Reinstalling the OS however worked. Then 1 week after that, the same thing. Tears, Screaming, nothing helped, I saw visions of ruined Logicboards etc.
But then... I found out that it started working normally after I set the Energy Saver Settings to Highest Performance.
But setting the Energy Saver Prefs to Longest battery kills it instantly and leaves only a way out via forced restart.

I now believe my battery is dead and has to be retired. It turned from full to empty within an hour - wich I never noticed before as I mostly used the Power supply.
I still don't know why a crap battery can do this at these settings, but for me this was definitely the cause and effect.
Good luck with your (hopefully) repaired PB!
Running OSX Server (10.2.6).

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A new way to resuscitate a dead battery
Authored by: bluehz on Jul 21, '03 01:18:42PM

I have an iBook 2001 (late, dual usb) that has been giving me problems for the last 3-4 months. It would charge fine, but when it got to about 80% it would drop instantly to 0%. Gave me about 15 mins of time on it. I tried everything including the nvram techniques and nothing worked. I finally decided the battery had just lived its life and was depleted, even though I have rarely even used the battery.

After reading the Macintouch article last week - I decided to give it one more go. Tried the nvram rest, let it charge overnight - tried it... no go same behaviour.

So I read the article again and noticed one persons comments about using OS 9 was the trick on REALLY stubborn machines. Well I decided to give it the ol' "Try # 378" - rebooting into OS 9. I have long since 86'd OS 9 on my iBook so I had to pull out an old OS 9 boot cd. The process said to reset the nvram (as explained in this article) then reboot to OS 9 and cycle the battery. So I reset the nvram, then booted off OS 9 CD and pulled the plug. Nothing... after 15 mins it died. So I plugged it in and let it charge in OS 9 for several hours. Pulled the plug... voila... it ran for 1.5 hours (with no activity on it, but hey its an improvement. Now the big test - will it stick in OS X. So I rebooted into OS X and it appeared to be working. First I got about an hour out of it, then the next recharge it returned to its old habits of 15 mins, die at 80%.

So the solution listed partially worked for me. One thing I have not tried that one of the submissions at Macintouch mention - was disabling the Battery menu extra. According to the author - it is the menu that crashes and takes down the PMU (that controls power management and charging) with it. I have yet to try that technique yet though.

In summary - if all else fails including the nvram solution - try this:
* Reboot into OS 9 and cycle battery (discharge completely, then recharge)
* Remove the Battery menu extra

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A new way to resuscitate a dead battery
Authored by: nchen on Aug 31, '03 04:36:38AM

Last night my girl friend's iBook went hairwired. The battery simply would not charge and there was this single L.E.D at the battery that simply would not go away. Furthermore, any prominent characteristic was that the battery indicator in OS X says that it needed 7:30 hours to charge! To cut a long story short, I tried every hint here but to no avail. Then, just for kicks I booted into os 9, just to see what will happen. Instantly, the battery was detected! And it was fully charged. After rebooting in OS X, this effect seems pervasive. So, this might just be the very last resort.

IMHO, some idiot who used her iBook did something seriously to the OS 9 partition because when it started up, it went into repair start up disk.

One more thing, after this reboot into OS 9, the computer seems a bit more responsive and not as sluggish as it was.

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A new way to resuscitate a dead battery
Authored by: 47ronin on Jul 21, '03 05:19:58PM

I doubt this would help Wallstreet PB users with original Apple-made batteries :) .. those are just plain screwed up.

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A new way to resuscitate a dead battery
Authored by: rkchang on Jul 21, '03 06:49:47PM

After reading all these tales of dead batteries and experiencing a few tales of my own, I feel compelled to add my two cents (or my tale).

To put it succinctly, I am incredibly happy that I bought the Applecare protection package, when I bought my dual USB iBook last July. For the last couple months, I had a similar problem that someone here posted: once my battery dropped to about 80%, it would instantly plunge to 0%. I finally decided to give Apple tech support a call. After I had told them that told them that I had tried the typical tricks (complete drain to recalibrate, resetting power manager, etc.), they offerred to send me a new battery free of charge. My iBook has been happy ever since.

They also let me know that if I had called any later, they wouldn't have been willing to send me the new battery. As it is, Apple only supports and warranties their batteries for up to a year, even if you buy the 3-year Applecare protection package. Apparently, they know that their batteries have an extremely low shelf life, and are hoping to make some extra $$ off of replacement batteries.

"I have seen the evils of procrastination, and I vow to change my ways tomorrow."

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A new way to resuscitate a dead battery
Authored by: phlavor on Jul 21, '03 08:32:41PM

I used to give the breath of life to old Wallstreet batteries using the following method:

1. plug in laptop
2. insert battery for 5 seconds
3. pull battery for 12 seconds
4. repeat steps 2 & 3 until battery is recognized
5. charge as normal

The idea behind this is that the caps in the Wallstreets have enough juice to burst charge the battery for the first 5 seconds of charging and then take another 12 seconds to regain that charge. They will burst charge anything conected wether the system sees it as a battery or not. When the battery is fully depleted it is not recognized and therefore not charged. I have had a 100% success rate with this method but I've only done it with Wallstreet and Bronze Powerbooks. Will it work on others? I don't know.

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I think my battery is beyond help!
Authored by: stevecopley on Jul 22, '03 04:48:05AM

Over the past few months my PowerBook G3 Firewire's battery has been holding less and less charge. It had got to the point where it would only give me about 25mins on battery, even after being plugged in all night. X-Charge would show a very steep drop-off as soon as the charger was un-plugged, I'd get a low-charge within a few minutes, and then the PB would shut off a few minutes later. (when new it was 3+ hours I think, certainly enough to watch a full DVD).

Things have taken a turn for the worse now. The battery will not charge at all. I have tried ALL of the hints listed here, and others...

- Reset the PMU (reset button on rear)
- Reset the PRAM (opt-cmd-P-R on boot)
- Reset-all in Open Firmware (opt-cmd-O-F on boot)
- Removing / Re-inserting battery repeatedly
- Booting into OS9 and trying to charge the battery overnight

All to no effect. The battery is recognised, but it firmly sits at 0%. X-Charge reports the following when the battery is removed and re-inserted...

2003-07-22 12:22:38: Battery removed
2003-07-22 12:22:43: Battery installed (current charge = 0%)
2003-07-22 12:22:43: Battery started charging (current charge = 0%)
2003-07-22 12:22:48: Battery stopped charging (current charge = 0%)

i.e. The system sees the battery, it starts to charge, then stops a few seconds later.

So... Is this a completely dead battery? It would seem so. Any other ideas?

I've had the PB for 2 years from new. A new battery will cost me £97 plus p&p which is not so bad, but obviously I'd prefer to get a bit more life out of this one first if possible!

All the best


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I think my battery is beyond help!
Authored by: claude on Sep 24, '03 06:17:16PM

I've got almost the same problem here, on a PowerBook G3, except that my battery has never been to the point of not being recognized. It always gets detected, under OSX, OS9 and Linux (I got three OSs on my Powerbook).
The problem is, it does not accept a charge. It sits there, at 0% for ever. Here too the OS used does not make the slightest difference. X-charge gives the same log, except it doesn't say the charge has stopped, but nevertheless, it remains at 0%.
I tried the above hint, also resetting the powermanager, resetting the PRAM (cmd-opt-P-R and let it chime 5 times) which also resets the NVRAM, if done from a cold start, but nothing helps.
I know the battery is not completely dead, as it still blinks, when in the PowerBook, and the Powerbook is plugged in and the little button on the battery is pressed. It blinks one of the LEDs for several seconds and that's it. Apparently batteries are only completely unrecoverably dead, when they don't even respond in that way anymore, so there is some hope - I hope!
BTW, I also tried the Battery Reset from Apple, although it is meant for the G3 Series PowerBooks, but that too didn't help. :(

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I think my battery is beyond help!
Authored by: Gabe462 on Sep 26, '03 07:15:30PM

Scuze my obliviousness, but where is the PMU button on my G3 bronze/firewire's battery? There's the charge indicator button, but I don't see anything else to push. Do I have to open the battery? Is it hidden in the connector somewhere? I figger I should at least start at the beginning before I try all them fancy steps.


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I think my battery is beyond help!
Authored by: osex314 on Sep 26, '03 08:33:54PM

Try finding your computer in the list here:

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A new way to resuscitate a dead battery
Authored by: thebimbo on Jul 23, '03 10:13:41AM

Folks, I too had problems with a *new* iBook (1st gen) battery. As a last resort after spending hours running thru the tips I finally tried running down the battery in the iBook - till battery 'dead' - and then trying all the tips and since then the battery and iBook behave together.


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A new way to resuscitate a dead battery
Authored by: simdude on Jul 29, '03 08:41:39AM

I too tried every tip I could for my ibook battery. I bought a second one and had no problems with it so the problem didn't seem related to the computer itself.

I was just about at my 1 year end so I gave Apple a call and managed to get a new battery. I'm convinced it got hosed after the 10.2.4 update. You might have to run around in a few circles since techinically, Apple will not take phone calls without Applecare after 90 days. I told them I wasn't calling for technical support however, just information about where to send back a defective battery still under the 1 year warranty. The second person I talked to was going to charge me the $49 one time call fee but I pleasantly explained how I had already tried all the suggestions from the first person at Apple I talked to. I think they have a little bit of leverage as to whether they will charge so if you call, be very nice and professsional and you may have the same good luck I did.

The new battery is working great. And since I saved the cost of the battery, I went right to my local Apple store and bought some more stuff.

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A new way to resuscitate a dead battery
Authored by: pmseng on Aug 24, '03 06:43:22PM

My battery problem is a bit different. One of my kids stepped on my power supply plug and broke the tip off. The PS still worked but I noticed the iBook's battery wasn't charging. I've since gotten a new power supply, but my battery is totally dead - no lights on the bottom of the iBook - and obviously it still won't charge.

However, I can't start my dual FW iBook with the battery removed either. Any thoughts as to why this might be?


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A new way to resuscitate a dead battery
Authored by: johnsawyercjs on Sep 26, '03 03:54:49AM

Here's a tip from Macfixit, and my response at the time:

Macfixit, Feb 27 2003:
Shorting an iBook's battery to reset it [my advice: use a fast-blow fuse instead]
Warning: Before we continue with this information, it's very important to note that you should not even consider attempting this procedure without the aid of a skilled electrician, and you should be aware that your iBook battery may be destroyed. Again, do not attempt this procedure on your own. Take your iBook battery to an authorized electrician or another specialist.

A Mac service provider who wishes to remain anonymous describes the process of shorting a defective iBook battery (which was temporarily ruined by static electricity), in order to restore its function.

"One of my clients was using an 800 MHz Combo 12.1" iBook purchased late 2002. As he was using the computer, he got a mild shock of static electricity from someone. It froze his computer (OS X), completely requiring a reboot. Upon reboot (plugged in to wall), the computer stated that no battery was present. After removing and reinstalling the battery, the computer stated the battery was at 0%, even though it was actually fully charged. The battery itself showed one steady light. Nothing he tried would change anything. It also would not charge, though the orange charge light would come on.

"We decided that the battery itself needed to be reset, since he knew it was fully charged (and only a couple of months old). Of course, with only one button to press, we couldn't reset it. By fluke, shorting out the two outermost power leads on the battery together, for a split second (still makes quite a spark) actually reset the battery. The four lights cycled from 1 to all on a couple times, and then all 4 lights came on.

"He inserted two small pins (the kind that you get with a new dress shirt) into the outermost contacts. Then, using a multi meter, he measured the voltage, and then briefly zapped the two together in a single 'motion.'

You should also include a fuse in the (short) circuit. Without a fuse there is a potential for the shirt-pins or other leads to electrically weld together and draw a huge current for an extended period. They'd also get very hot, making it difficult to remove before damage was done.

If you are one of the several readers having an iBook battery problem, you should first attempt invoking your Apple warranty or AppleCare (if you purchased the coverage) before attempting home repairs such as the one described above.

UPDATE: James Sentman offers some further explanation on why shorting the battery works, and further caution about the procedure:

"I might be able to shed a little light on why shorting out the battery would cause it to reset. Every lithium ion battery pack has a set of sensors and circuits to protect the batteries from things like charging at high temperatures, complete discharge, and short circuits. If this chip sees excessive power drain like from a short, it will temporarily disconnect the cells to protect them from catching fire or exploding. So by shorting it out you are basically power cycling the other circuit in the pack that keeps track of the power level in the battery. However, even with this protection built in it is important not to short the battery for more than the moment necessary to do this. While I have no reason to think that these circuits are prone to failure, if you're lucky enough to get one that is not functioning, shorting the battery will cause the cells to catch fire and even explode very quickly without this protection."

Posts in response:
Authored by: jonsaw on Thursday, February 27 2003 @ 01:37 PM PST
I'd recommend using a fast-blow fuse in-line with the wires you're
using to short the battery contacts, instead of simply using wires
or pins alone. A half-amp fuse should do the trick. If you find that
a fast-blow fuse opens too quickly, try a regular fuse. Since it's
still possible the battery could explode, you might also want to put
the battery into a box, with holes for your hands, and wear thick

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