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MBP Running slow when its on batteries .. working fine when plugged to the charger ?!

Hi there !
I noticed that my MBP is running very slow when it's on batteries.. but when plugged to charger it works fine..

Is the battery drained already ? I purchased it OCT 2011 but has been using it lightly for almost 5 months ..

P.s : I cleaned it up coz I thought its a space or piled files issues but it didn't work




Thank u in advance 🙂

MacBook Pro, Mac OS X (10.7)

Posted on Jan 5, 2013 1:14 PM

Reply
88 replies

Jul 20, 2017 9:56 AM in response to RoXy1988

I just tried this on a mid-2010 Macbook Pro on a fresh installation of macOS Sierra. The computer had a history of water damage but there was no damage visibly obvious on the board. It had been examined by Apple several years previously when water damage had occurred. The computer had sat for a year or two without use and had such a badly bloated battery that the touchpad was popping out of the front about an inch (hard to believe the touchpad could withstand this..). After installing a new battery, doing a fresh install of Sierra, doing a hard reset with the battery out and repeatedly resetting the SMC the computer continued to exhibit signs of SMC issues -- the keyboard backlight was vacillating between on and disabled and the computer was running so slowly when it was off the charger that it was nonfunctional. The computer failed Apple Hardware Test for sensor failure: 4SNS/1/40000001:VP0R-0.000.


I am guessing that this sensor is in some way related to the battery and how the SMC detects it and adjusts the computer's power settings accordingly. Removing this KEXT resolved all the visible SMC issues like the vacillating keyboard backlight and the slowness off the charger. The changes were persistent across shutdowns and after running the Sierra 10.12.6 update the changes remained. With the KEXT removed I haven't noticed any differences between fan operation or CPU temp in stress testing and the computer is correctly recognizing that it's running on battery when it's off the charger.


Although this fix works for the visible symptoms, Apple power components are intricate and altering SMC settings have pretty serious implications, including overusing and overheating your motherboard from a lack of proper settings. Although I implemented this I'm continuing to monitor the computer. This problem indicates a motherboard sensor or component failure. Ultimately, if you're having this issue running Apple Hardware Test or Apple Diagnostics wouldn't be a bad idea.


Apple Diagnostics is the newer version of AHT and is available on computers released June 2013 and after. You can hold down D at startup (after the screen comes on) to access either of these tools. More information on these diagnostics:


How to use Apple Diagnostics on your Mac - Apple Support

How to use Apple Hardware Test on your Mac - Apple Support


For some older computers, an external CD is required. If you don't have this CD, you can find the version of AHT that fits your model computer (7,1, 8,1, etc.) online. If anyone has similar experiences and runs the diagnostics, it would be interesting to hear the results.

Jul 26, 2017 6:46 AM in response to tony_stead

Thanks a lot man. It really worked. I tried many option to fix this. First i thought battery is faulty then i swapped with another one from my friends macbook pro . But no solution. But this one worked for me. Though i had to disable system integrity check from recovery mode to delete that file. But it really worked , big thanks for sharing this knowledge.

Oct 16, 2017 5:30 PM in response to tony_stead

It worked just fine with Sierra. Now I just updated to High Sierra and the problem came back. I repeated the process and it worked again like a charm! Thank you!


Just noticed the file in my case is MacBookPro8_1.plist and its path is slightly different:


/System/Library/Extensions/IOPlatformPluginFamily.kext/Contents/PlugIns/ACPI_SMC _PlatformPlugin.kext/Contents


MacBookPro8_1.plist to trash!

Jan 6, 2013 8:26 AM in response to RoXy1988

Reset the SMC, then test your MacBook Pro again.


SMC reset:


Before Resetting the SMC


Try each of the following steps in this order before you reset the SMC. Test the issue after completing each troubleshooting step to determine if the issue still occurs.


  1. Press Command + Option + Escape to force quit any application that is not responding.
  2. Put your Mac to sleep by choosing the Apple () menu from the upper-left menu bar and then choosing Sleep. Wake the computer after it has gone to sleep.
  3. Restart your Mac by choosing the Apple () menu from the upper-left menu bar and then choosing Restart.
  4. Shut down your Mac by choosing the Apple () menu from the upper-left menu bar and then choosing Shut Down.


Resetting the SMC on portables with a battery you should not remove on your own


  1. Shut down the computer.
  2. Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
  3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
  4. Release all the keys and the power button at the same time.
  5. Press the power button to turn on the computer.

Jan 7, 2013 10:30 AM in response to RoXy1988

This is normal. The battery may appear to stop charging between 93 percent and 99 percent. The batteries used in these computers are designed to avoid short discharge/charge cycles in order to prolong the overall life of the battery.


If you think it is still running poorly while on battery power there may be an running process causing this that you may be able to fix. To determine what it might be read:


Runaway applications can shorten battery runtime


If you cannot find any obvious runaway process, consider performing the following two troubleshooting steps:


Creating a temporary account to isolate user-specific problems: Isolating an issue by using another user account


Safe Mode or "Safe Boot" is a troubleshooting mode that bypasses all third party system extensions and loads only required system components. Read about it: Starting up in Safe Mode


If after performing these procedures you still think something is wrong, schedule a Genius Bar appointment:


Genius Bar Reservations: http://www.apple.com/retail/geniusbar/

Aug 1, 2013 7:58 AM in response to RoXy1988

Try this at your own risk - It Worked for me after a complete system reload which didn't make any difference.


I will take no responsibility for any damage or loss caused to you or your property. Do it of your own free will and at your own risk.


I did this on a MacBook Pro Early 2011 - 2.7 GHz Intel Core i17

System Version 10.6.8 Snow Leopard


Running well on mains power but dramatically slowing down when running on battery power


First try this to see if you get the same result I got


Quit all programs

With the mains connected

Open Activity Monitor and click on CPU in the bottom half of the window

Check the CPU Usage graph - It will probably be minimal - Under 1%

Now disconnect the mains and watch the graph shoot up and CPU activity around 80%


Here's what I did...


Again - I will take no responsibility for any damage or loss caused to you or your property. Do it of your own free will and at your own risk.


Firstly, you’re going to need the model identifier of your Mac,

go to the Apple in the menu bar and select "About this Mac"

When the About this Mac pane appears click on "More info…"


Select Hardware in the left panel

In the right panel make a note of the Model Identifier e.g. "MacBookPro8,1"


Now open a finder window and click on Macintosh HD

Click on system >Library > Extentions

Find the kext file called IOPlatformPluginFamily.kext

Right click it and Show Package Contents

Click on contents

Click on Resources

Click on PlugIns

Right Click on ACPI_SMC_PlatformPlugin.kext

Right click it and Show Package Contents

Click on contents

Click on Resources

Find the the plist file that corresponds to your Model Identifier e.g. "MacBookPro8,1.plist"

Move it to the trash and delete it

Restart and everything should now be fine.

MBP Running slow when its on batteries .. working fine when plugged to the charger ?!

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