You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

MacBook Pro 2011 Battery Re-Charging Issue

Hey everyone, I discovered a problem on my 2011 MBP 17" which I was told that "it's perfectly normal' and I want to see if you guys can reproduce it on your new 2011 models as well (please indicate your screen size).

In summary, I noticed that depending on CPU usage, the battery reacharge time will greatly fluctuate to the point where the laptop just stops charging the battery. I noticed the giant fluctuations in time when I booted one of my VMs which used up like 15-20% overall cpu usage. I was at 5% battery life and the computer was plugged in recharging and the battery indicator all of the sudden went from somewhere around 2.5 hours recharge time to 10 hours to 15 then 20 hours. Then at some point the magsafe light went green and the battery indicator showed 'Not Charging'.

I thought that I may have a bad MagSafe so I tried the one from my 2009 MBP (both are the 85W version) and bam same problem. I figured that this may be due to a design flaw where the power unit cannot supply enough tower to feed a CPU that's being somewhat taxed (i'm talking about 25-50% usuage) and recharge a battery.

Here is a simple way to try to reproduce the problem:

1. Let you battery drain to about 80% or less.

2. Close all open programs.

3. Change your battery indicator icon in the menu bar to display the info as 'Time'.

4. Plug in your MagSafe and let the recharge time in the battery indicator calculate and stabilize (give it about 2 mins to get a stable time value).

5. Open up safari and go to Hulu and play any TV show to drive up your cpu usage.

6. Then open Terminal and type the command 'yes' (without the quotes) and hit enter. The 'yes' command basically causes an infinite loop of the letter 'y' to be display in the terminal window which also taxes your CPU in addition to the video playing in Hulu.

7. Now watch the battery indicator's recharge time value and you should notice that it'll start going up significantly in time and at some point it'll say 'Recalculating' and eventually it'll give up and say 'Not Charging'. I have a 2009 MBP 17" C2D 2.66GHz, and although the recharge time goes up by 20-30% in the exact same test, it at least still charges the battery.

I was able to reproduce this at the apple store on a 17" 2011 model as well but I'm curious if this also happens on the 15 and 13 inch models. I was told by the engineering team on the phone that this is 'perfectly normal'. I guess it falls in the category of malfunctions as designed...

null

null

2011 MBP 17" anti-glare, Mac OS X (10.6.6)

Posted on Mar 18, 2011 4:29 PM

Reply
186 replies

Apr 15, 2013 10:04 AM in response to studyplenty

If anyone's interested, here's the closest thing to a workaround I've come up with based on my testing.

The steps are different depending on the OS you're running.


10.6.8 -

download this program CPUPalette (its part of xcode, and can also be extracted from a 10.6.8 dvd using pacifist) and use it to disable all but one core of your cpu, as well as hyperthreading. no matter how hard you push the system with 3/4 cores disabled, it will not drain. This will not persist through boot and needs to be done every time you restart. You also have to keep cpu palette open.

https://mega.co.nz/#!YUohlQ7a!WDRrImiMN1fxJyrFvfJ8IFCYCfUZLxRGlx_YR_Ktq9A


10.7 and 10.8 -

install xcode from mac app store:

https://itunes.apple.com/us/app/xcode/id497799835?mt=12


Once installed, open up Instruments, and look in it's preferences window. It should have a slider in there to adjust cpu cores and a checkbox to disable hyperthreading as well. Use this the same way as cpupalette to disable cpu cores.


Until apple owns up to their defective design and does something about it, this is all you can do.

I wouldn't hold my breath on that one though.

Oct 25, 2013 10:08 AM in response to TheRosta

If anybody is still running one of these machines that has this issue, I'm hopeful 10.9 Mavericks will solve this problem for us, since it has such a big focus on energy savings and performance, with any luck this issue will have been looked into during testing and resolved. When I update, I'll run the same tests and report my findings for everyone here.

Nov 2, 2013 1:06 AM in response to FlyEvolution

UUnfortunately I am able to drain the battery while on AC with Mavricks. (Late 2011 15" i7 2.2Ghz, 16GB ram, 750GB 7.2k rpm HDD, high res display)


If I run multiple CPU intensive virtual machines in Parallels I can view the energy graph in activity manager drop all the while indicating I'm charging (green).


I think this is an engineering failure in the total sum of all energy consuming parts exceed the supply, luckily the charging circuits allow the battery to help. I would guess this is one reason the battery is not user serviceable?


anyway whatever the cause - it's a hardware issue that an OS change can only mitigate, not resolve.

MacBook Pro 2011 Battery Re-Charging Issue

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.