Abies_Balsamea
Level 1 (0 points)

Q: 1) Why does 3 1/2 yr old MacBook Pro drain battery while connected to AC? Has rarely been used off AC; then only for an hour or so. 2) Please advise if action needed.

1) Why does 3 1/2 yr old MacBook Pro drain battery while connected to AC? Has rarely been used on battery/off AC, and then just for an hour or so.

2) Please advise if action needed. I know little about battery behaviour & how to prolong its life. My energy settings are quite conservative & I shut down completely every night. Am hoping battery is not dying. Many thanks!!

MacBook Pro, Mac OS X (10.6.8)

Posted on Jan 18, 2015 7:55 PM

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Abies_Balsamea

Q: 1) Why does 3 1/2 yr old MacBook Pro drain battery while connected to AC? Has rarely been used off AC; then only for an hour or so ... more

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  • by spudnuty,

    spudnuty spudnuty Jan 18, 2015 8:20 PM in response to Abies_Balsamea
    Level 5 (7,097 points)
    Mac OS X
    Jan 18, 2015 8:20 PM in response to Abies_Balsamea

    Hello Abies_Balsamea and welcome to Apple Support Communities,

    First try:

    Reset SMC

    http://support.apple.com/en-us/HT201295

    Look at this:

    Mac notebooks: All about batteries - Apple Support

    Common practice seems to be let the battery discharge to about 20% once a month.

     

    Also go to the Power section of System Report. Go under the Apple - About this Mac - More Info - System Report- Power

    Like here:

    Power System report.png

    report what that says

  • by Abies_Balsamea,

    Abies_Balsamea Abies_Balsamea Jan 18, 2015 9:24 PM in response to spudnuty
    Level 1 (0 points)
    Jan 18, 2015 9:24 PM in response to spudnuty

    Here are data from the Power section of System Report:


    Health Info: Cycle Count 25

    Condition: Normal


    Charge remaining: 1563

    Full Charge Capacity: 6748


    AC Charger Info:

    Connected: No

    Charging: No


    This last is weird because the MacBook is plugged into a clearly functioning power strip that I've checked and rechecked.


    Am scared that battery will drain all the way and I won't be able to communicate if laptop can't function w/out battery.


    Oh!! It's just begun to charge after getting to 31% power left. Now yesterday it let itself drain to 56% left, then began to charge. Dear Spudnuty if this helps you help me understand what is going on I'll be so relieved. THANK you!


    I've looked at some general info about battery life on my model & since I didn't know about letting it go down to 30% once monthly I wonder if it has started to take this step itself? To try to help itself? Or am I misreading?


    I appreciate your help,

    Abies_Balsamea

  • by spudnuty,

    spudnuty spudnuty Jan 18, 2015 9:37 PM in response to Abies_Balsamea
    Level 5 (7,097 points)
    Mac OS X
    Jan 18, 2015 9:37 PM in response to Abies_Balsamea

    "Health Info: Cycle Count 25"

    Well that count is really low, especially for a 3 1/2 year old MBP. Original battery?

    "Oh!! It's just begun to charge after getting to 31% power left. Now yesterday it let itself drain to 56% left, then began to charge."

    Hmmm well Apple used to say to let it discharge to 20% once a month but now there's no mention of that.

    MacBook Pro... To Charge or not to Charge

  • by Abies_Balsamea,

    Abies_Balsamea Abies_Balsamea Jan 18, 2015 10:33 PM in response to spudnuty
    Level 1 (0 points)
    Jan 18, 2015 10:33 PM in response to spudnuty

    Yes it's the original battery.


    I don't know what the "Cycle Count" is.


    I've just followed the instructions for resetting the SCM. I have also been having mysterious overheating issues so thought it was a good idea, but can't tell what the result was.


    My computer has stopped recharging again and is now showing a red 21% charge left in the battery.


    What do I do??? If anyone can help, I would be so glad. PLEASE.