candrews90

Q: MacBook Air turns off randomly when unplugged

Hi all,

 

I have a 2011 13" MacBook Air running Mac OS 10.10.2. I have upgraded the SSD to a Transcend JetDrive 500 240GB, and recently replaced the battery with a genuine Apple MacBook Air 13" battery bought on eBay. I will include a screenshot of coconutBattery with battery stats.

 

Until yesterday evening/this morning, my laptop was running fine. I first noticed the problem when one of my family members was using the laptop, the battery charge was about 40% and the laptop just turned off unexpectedly. I thought originally the battery may have been dead or nearly, but I plugged it in and the charge was ~39%. The whole time the laptop was plugged in, there were no issues. I unplugged the laptop and put it in my bag to go to University, and I didn't know at this time if it had turned off or not.

 

Fast forward to this morning, went to use my laptop, and sure enough the laptop turned off within 5 minutes, keeping in mind the battery was no where near dead. Now this is where it gets strange. I tried turning my laptop on and this time it wouldn't boot, it got to the Apple logo, the loading bar appeared and after 30 - 40 seconds (way longer than an SSD should take to boot), I was presented with the grey circle with a line. So I thought I'd try safe mode, a

 

nd it booted fine, albeit very, very laggy. Noticed nothing strange, shut down the computer and tried booting again, no luck. Tried resetting SMC and PRAM (3 times to be sure for PRAM), but it made no difference. Tried booting into recovery and repairing disk permissions. Everything was fine, even the SMART check said the OS X partition was fine. I thought I would try Single-User Mode, but when it loaded, I couldn't try to run fsck, no input of text was allowed, and eventually the colours on the screen became washed and the circle with a line through it appeared.

 

I then thought perhaps it was Trim Enabler causing the issue with the new kext signing Apple has introduced with Yosemite, so I booted into recovery, and ran the disabling command through Terminal. At this point I don't know if the laptop was plugged in or not, because sure enough when I quit Terminal and rebooted, the computer booted! I have since disabled the kext signing and the computer booted no problem. Since then, I have unplugged the laptop once, and within 10 seconds it had switched off, even though the battery was at 100%! So, I've established the computer only wants to remain on if I have it plugged in to the mains. The battery in the laptop is very new, only about 50 cycles, and my previous battery had over 600 and just didn't hold the same charge any more. Also, ignore the manufacture date coconutBattery states, as I purchased it less than 3 months ago.

 

So I wonder, does anyone have any ideas as to why the laptop dies instantly, and what may have caused the seemingly endless kernel panics.

 

Thank you,

Chris.

Screen Shot 2015-03-10 at 18.45.37.png

MacBook Air, OS X Yosemite (10.10.2)

Posted on Mar 10, 2015 11:47 AM

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Q: MacBook Air turns off randomly when unplugged

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  • by my ginger,

    my ginger my ginger Mar 10, 2015 12:23 PM in response to candrews90
    Level 4 (2,472 points)
    Mar 10, 2015 12:23 PM in response to candrews90

    Did you install the battery or did apple store do it? OK. The trouble with coconut battery and even reading the settings in system under about this mac is that, while helpful is not complete.  It shows mAh and not volts. Lets see if I can explain. Lets say you have a car with this problem. To find out if the battery is bad a repair shop would run a load test.  This would show voltage as well as amps.At 100% charge it would show 12.5 volts , and after put under a load it drops to 8 volts. That would mean the battery is defective ,even though the amps are still good.In the case of a computer battery , this would be hard to determine. The apple store may have the ability to test beyond what you can do. The only load test that you can put on it is to use it under battery only.  While it shows 100% charge, if the charge percentage drops off fast while in use or shuts down. It could point to a battery that only holds a surface charge. I am not saying it is the battery. But as you have done An SMC reset and A pram reset. the only thing you could do is take it in to apple to let them test it.

  • by OGELTHORPE,

    OGELTHORPE OGELTHORPE Mar 10, 2015 12:48 PM in response to candrews90
    Level 9 (52,725 points)
    Mac OS X
    Mar 10, 2015 12:48 PM in response to candrews90

    Open System Information>Power and post this from your MBA:

    (make certain that the charger is connected)

    Screen Shot 2013-08-22 at 7.19.46 PM copy.png

    Ciao.

  • by candrews90,

    candrews90 candrews90 Mar 10, 2015 1:15 PM in response to OGELTHORPE
    Level 1 (0 points)
    Mar 10, 2015 1:15 PM in response to OGELTHORPE

    Thanks for both of your replies! Yeah, I changed the battery myself following a guide on YouTube. I see in your screenshot OGELTHORPE that your voltage is 12000+ whereas mine is only 8000+. Do you think this is the problem and what is probably causing it? A defective battery or something more serious?

     

    Thanks,

    Chris.

    Screen Shot 2015-03-10 at 20.11.35.png

  • by my ginger,

    my ginger my ginger Mar 10, 2015 1:39 PM in response to candrews90
    Level 4 (2,472 points)
    Mar 10, 2015 1:39 PM in response to candrews90

    I stand corrected in that it will display voltage. but as (mV) But that is very low if you are showing the battery at 100% or close to. You still could have a defective battery. Or a problem with your charging system. When battery drops to ,lets say 80% does your mag safe go to orange? Or stay at green?

  • by OGELTHORPE,

    OGELTHORPE OGELTHORPE Mar 11, 2015 10:22 AM in response to candrews90
    Level 9 (52,725 points)
    Mac OS X
    Mar 11, 2015 10:22 AM in response to candrews90

    Perhaps an Apple Hardware Test will provide a clue:

     

    https://support.apple.com/en-us/HT201257

     

    Note that an error free AHT is not definitive.

     

    Ciao.

  • by candrews90,

    candrews90 candrews90 Mar 12, 2015 11:21 AM in response to my ginger
    Level 1 (0 points)
    Mar 12, 2015 11:21 AM in response to my ginger

    I can't tell since I can't use the laptop long enough to get the battery down to say 80% because it turns off when I unplug it! However, at the moment, it's sitting at 99% with the magsafe charger light being green, but I doubt this is a big issue.

  • by my ginger,

    my ginger my ginger Mar 12, 2015 11:50 AM in response to candrews90
    Level 4 (2,472 points)
    Mar 12, 2015 11:50 AM in response to candrews90

    I take it that before you changed the battery, you were not having this problem. Am I right? Have you done a SMC reset. Command/Option/Shift key and power button for 10 seconds with power cord plugged in. In order to get a genuine apple replacement battery on Ebay, they would have to be an apple reseller. IF these are the same problems you were having before you replaced the battery. Then it's carrying forword. Or the battery off Ebay is defective.

  • by candrews90,

    candrews90 candrews90 Mar 12, 2015 12:39 PM in response to my ginger
    Level 1 (0 points)
    Mar 12, 2015 12:39 PM in response to my ginger

    Hi again,

     

    Well as I said, I changed the battery a couple of months ago max, and there wasn't this problem until 4-5 days ago. I will be going home tomorrow and changing the battery back to my old one to see if it is indeed an issue with the new battery. I ran the Apple Hardware Test as suggested, both a simple and more extensive test, and it showed no problems. The only thing I noticed was that the voltage while connected to the charger was 8.32V under the power submenu in the Apple Hardware Test. I'll include a photo, so perhaps this confirms it is a problem with the battery and hopefully not something more serious.

     

    Optimized-IMG_20150312_190132.jpg

  • by candrews90,

    candrews90 candrews90 Mar 12, 2015 12:41 PM in response to my ginger
    Level 1 (0 points)
    Mar 12, 2015 12:41 PM in response to my ginger

    Sorry for the double post, I can't seem to be able to edit any of my posts. Yes, I did reset the SMC at least twice, so I think that rules that issue out. If I put the battery in this weekend (my old one) and it works fine, then it is indeed a defective battery, which I am really hoping for. Is there anywhere other than Apple to get a genuine but cheaper replacement battery since I think Apple's prices are rather ridiculous.

  • by my ginger,

    my ginger my ginger Mar 12, 2015 12:58 PM in response to candrews90
    Level 4 (2,472 points)
    Mar 12, 2015 12:58 PM in response to candrews90

    In your hardware test post. You should have been seeing a charge rate from the power source of at least 12.4 volts. Is it possible the mag safe is getting bad? As far as replacement batteries. I have used Ebay, but I look for ones with a return option and a one year warranty.https://support.apple.com/en-us/HT203207

  • by candrews90,

    candrews90 candrews90 Mar 12, 2015 2:36 PM in response to my ginger
    Level 1 (0 points)
    Mar 12, 2015 2:36 PM in response to my ginger

    Yeah, it seems like this 8V business is becoming a regular occurence now. I know someone who has the same charger as myself, so I can test theirs with my laptop and see if it is the mag safe charger. As for the battery, I'll have to check if there was a warranty or return policy, and if it is the battery I'll have to try get my money back since it is defective. Thanks for your continued help!