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PowerBooks, iBooks falling asleep without warning

PowerBooks, iBooks falling asleep without warning

Response has been tremendous to last week's report of PowerBooks and iBooks suddenly falling asleep, with hundreds of afflicted readers chiming in.

All models affected Virtually all Apple portables capable of running Mac OS X 10.3.x (Panther) are affected by this issue. So far we've received reports of the problem with the following systems:

  • iBook G3 (Clamshell)
  • iBook G3 Dual USB
  • iBook G4
  • PowerBook G4 12" - one of the most frequently reported, and the model affected by this issue in-house
  • PowerBook G4 15" (Aluminum)
  • PowerBook G4 Titanium
  • PowerBook G4 17"
  • PowerBook G3 (Pismo)
  • PowerBook G3 (Lombard)

Panther the culprit in most cases Most reports indicate that the problem started happening with Mac OS X 10.3.0, though for a number of users, it only started with one of the incremental Mac OS X 10.3.x updates - primarily Mac OS X 10.3.3. A significant portion of readers also report the problem in Mac OS X 10.2.x - primarily Mac OS X 10.2.8.

Henry Shites writes "Since updating my ibook (800 mhz) from 10.2.6 to 10.3, I've noticed a drop in battery performance. Since updating to 10.3.3, it has gotten much worse. I updated to 10.3.3 specifically because it was supposed to improve battery performance but now it's almost like watching the fuel gauge on a car with a hole in its gas tank."

Interestingly, Apple has a Knowledge Base article regarding this issue in Mac OS X 10.2.x, stating " The PowerBook or iBook goes to sleep without displaying a low-battery warning." and offering the solution: "Connect the computer to its power adapter once it goes to sleep."

Gareth Johnson is one of the users who is experiencing this issue with Mac OS X 10.2.x: "Both my wife (PB G4 1gb 10.2.8 ) and I  (PB G4 500mhz 10.2.8) have exactly the same problem after updating to 10.2.8. "

Making the problem even more complex, in some cases, Mac OS X 10.3.3 has actually resolved the unexpected sleep issue:

"I've seen the opposite result... Prior to updating from 10.3.2 to 10.3.3, my G4 TiBook (1GHz) would always suddenly go to sleep, when the "percent charge remaining" still showed around 18% to 20% charge remaining. (and there would be no warning, at all).

"Now, after updating to 10.3.3, the PowerBook is able to get down to about 5% charge remaining, and then a warning pops up, saying that the laptop is about to switch over to the reserve battery. [...] So, in my case, the latest system update actually seems to have solved this frustrating problem, instead of causing it."

Amount of power remaining when unexpected sleep occurs The time at which PowerBooks and iBooks unexpectedly fall asleep varies from case to case. Most reports (and our in-house experience) indicate that systems are much more prone to the problem when available battery time falls below 30 minutes.

MacFixIt reader Steve writes "I too have seen this both before and after the 10.3.3 update. It happens every time for me. Basically if my battery meter says 30 or so, my PowerBook could go to sleep at any second."

For some users, however, the problem is occurring when a more significant portion of battery life remains:

Harvey Riekoff writes "After the battery shows 100%, it quits suddenly at about 85%"

Thomas Maney writes " My memory is that a had at least 50% left on the battery - and the machine just went to sleep without warning and would not wake up. I immediately plugged in a power source, and the unit woke up showing only 1% battery life."

Worth noting, a disproportionate number of reports peg the unexpected-sleep point at around 12% or 27%. We're not sure what (if anything) is significant about these specific points in battery capacity.

Happens more frequently with some activities? Some users report that the unexpected sleep issue happens more frequently during disk, graphics, or audio intensive activities - including watching a DVD or listening to music through the built-in speakers.

If you are noticing the problem occurring more frequently while using certain applications or performing certain activities, please drop us a line at

How often the issue occurs In-house, the unexpected sleep issue occurs in less than half of low-battery situations. Some users, however, report that the problem manifests with much greater frequency:

Brett Stewart writes "Yes, my 1GHz 15" Tibook running OS 10.3.3 has the 'no warning before sleep problem.' It happens this way 4 out of 5 times, 1 out of 5 times it's normal."

Screen darkness - then revival A handful of readers report that - in a possible variation of this issue - the portable screen goes dim for a few seconds, then suddenly re-ignites:

Steve Prindle writes "Occasionally, by which I mean once or twice a day, the screen of my 12-inch G4 powerbook suddenly goes black and then -- one hippopotamus, two hippopotamus -- comes back on. While I'm not 100 per cent sure, I believe I never experienced this problem before installing Mac OS X 10.3."

Second battery in Pismo ignored Stephen Joniak experienced the unexpected sleep issue, but with an interesting twist - the second (charged) battery in his PowerBook G3 (Pismo) was ignored when the first battery's low charge triggered automatic sleep:

"Since upgrading to Mac OS X 10.3.3, my Pismo also just goes to sleep without warning - even when it seems there is a good 20 mins or more left on the charge. I found it also happened with 2 batteries in each bay - the second battery was ignored - so when the system felt the main left battery was running low it went to sleep regardless if the right bay battery was fully charged or not."

Erratic battery lights In a possibly related, but likely separate issue, MacFixIt reader Gregory Stobbs reports erratic behavior from his PowerBook's battery charge indicator lights:

"I too am having this sleep-without-warning experience. Although it may not be related, I recently noticed that the battery lights on my PowerBook 17" do not behave normally. Sometimes they flash on and off erratically. Even when fully charged, only one light is lit most of the time. The battery life seems rather short as well. I have tried the battery update program and also reset the power manager. These steps did not seem to help."

Calibrating the battery Knowledge Base article #86284 explains the PowerBook/iBook re-calibration process, which may work to correct this problem in some instances:

"The Lithium Ion battery of an iBook or PowerBook computer has an internal microprocessor that provides an estimate of the amount of energy in the battery during charging and discharging. The battery needs to be re-calibrated from time to time to keep the on screen battery time and percent display accurate. You should perform this procedure when you first use your computer and then every few months thereafter."

Resetting the PMU Some users have reported that resetting their portables' PMU solved this issue. Apple provides details for performing the reset procedure for a number of portable models in Knowledge Base article #14449.

Using " SlimBatteryMonitor" One solution that has proved successful for some readers is the usage of a third-party battery monitoring utility. Michael Sugerman suggests "SlimBatteryMonitor":

"I've taken to using the app "SlimBatteryMonitor" which puts a battery level icon in the menu bar and has an option that allows you to set it to give a warning when your battery hits a predetermined power level."

Version 1.1 of SlimBatteryMonitor also has a nice feature for users of PowerBooks with two battery bays: the second battery's remaining time can be estimated from the first battery's power characteristics. Also, times and percentages are now aggregated across both batteries.

Using a power adapter In-house, the method we most often use for solving this problem is the simple connection of a power adapter. Doing so usually allows the PowerBook to wake up properly (restoring interrupted open projects) and usually allows several more minutes of charge time even if temporarily connected to the external power source.

Bo Westerlund confirms this behavior, finding a good chunk of his battery charge still available after temporary connection to a power source subsequent to the unexpected sleep:

"Yesterday my iBook fell asleep with half full battery. I was really surprised. When I plugged the power adapter in it started without problem showing 75% battery left."

Other users' portables display zero charge despite indicating a significant charge before the unexpected sleep:

MacFixIt reader Forrest writes "Same issue, often with the battery indicating >20% charge. I'm using a 12" powerbook 867, and the battery is less then 2 months old. When I plug in and wake the unit, the battery then is at 0% charge."

However, it should be noted that some users are not able to awaken their portables even after being plugged in, with a manual restart required:

Seth Benjamin writes "Not only does my PowerBook no longer remind me about low battery, but if it goes into low power sleep mode, it never comes back up after being plugged back in. If the display goes black and the power light pulses like it's waiting to be plugged in, I cannot get her back up. I have to unplug, pull the battery and wait about 3 minutes for the PRAM battery to discharge and the power light to go off permanently. Then she'll boot. This never happened before Mac OS X 10.3.3."

Other PowerBook battery issues

0% charge An issue with PowerBook/iBook batteries stuck at a 0% charge, which has been previously noted, is cropping up with more frequency since the Mac OS X 10.3.3 update. Generally a constant 0% charge indicates a faulty battery:

Jason Wolf writes "After the Mac OS X 10.3.3 update I noticed that my laptop would just go to sleep with no warning. Now I have a much worse problem - I turned on my laptop and noticed the battery indicator was at 23% - then boom, it turned off, not sleeping, just turned off. Then when I plugged in the charger, it won't charge! The battery is completely dead - registers a 0% and resetting the PMU did nothing. My second battery (after putting it in) charged fine."

Another reader writes "My battery stays at 0% all the time, and in the 'remaining time' field, there is the 'calculating..."'message. My powerbook was purchased 3 months ago (apple refurb) and I have done light use on the battery."

The above-mentioned PMU reset and re-calibration methods are sometimes successful in reviving "stuck at 0%" batteries.

Battery life span/degradation Exactly how quickly do PowerBook/iBook batteries begin to lose their full charge capacity? MacFixIt reader Paul Vail reports that his battery lost a fairly significant amount of capacity in only two months:

"I do see that the battery is aging from just a couple of data points:

  • January 30, 2004: 3174 mAh max
  • April 4, 2004: 2887 mAh max

"So over a 2 month period with approximately 40 recharge cycles, the max of this battery has declined to 91% of its capacity at the time I applied the battery update."

Paul also reports that his PowerBook discharges much more quickly during sleep since applying the recently released Apple Battery update:

"One thing I have noticed over the past many weeks since applying the battery update to my PowerBook G4 867 12" is that the battery performs worse than prior to the update.

"For instance, the powerbook appears to discharge the battery aggressively even after the lid is down and in sleep mode. I can have 20 to 50% of battery remaining, close the lid, and open the powerbook some hours later to find the battery completely exhausted. Running the PB off of battery in a normal fashion does not indicate an abnormal discharge through normal use, so I don't believe the battery predictor is off greatly -- the Powerbook simply seems to use the battery at a much greater rate while in sleep mode than it did prior to the update."

We previously reported that users purchasing new batteries have experienced greatly improved charge capacity.

Jump from one measurement to another Chico Woodhill reports a problem, for which we are seeking confirmation, where the battery life indicator suddenly jumps from one measurement to another:

"My 667 MHz TiBook has picked up a variant of this problem. Battery power drops normally to somewhere around 30%, then somehow makes a quantum drop to around 7%. It never registers the range in between these values. It then proceeds to go to 0% power and forced sleep, usually without any low battery warning. Occasionally I get the warning, but usually not."

  • article
  • #86284
  • #14449
  • "SlimBatteryMonitor"
  • purchasing new batteries
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