Kernel task uses >800% of CPU - MBP is useless now.

Discussion in 'MacBook Pro' started by megaRa24, Feb 17, 2013.

  1. megaRa24 macrumors newbie

    Feb 16, 2013
    :confused: I have kernel task problems. it is using >800% of cpu (YES, eight hundred percent). it slows my 15" macbookpro 8,2 (mid2011) in all functions down to unusability. system usage of cpu at activity control shows about 90% permanently even though there is nothing to do. the download of 35MB took almost 2 hours at a speed of 7KB/s. my battery is somehow involved, too. the mac is useless like it is now. :mad:
    I hope someone can help about it. if u post it here, I will check again later. thx.
  2. simsaladimbamba

    Nov 28, 2010
  3. alphaod macrumors Core


    Feb 9, 2008
    First I would reboot the computer.

    Next, I would repair disk permissions, reset the PRAM and SMC.

    Then check out the console logs to see what is causing the issue.
  4. Ledgem macrumors 65816


    Jan 18, 2008
    Hawaii, USA
    In addition to alphaod's advice, while you're in Disk Utility I would also verify your disk. I've had some minor file system corruption due to forced shutdowns, and occasionally it causes problems when the computer tries to back up to Time Machine.

    If an error is found, you will be asked to boot into recovery mode to repair the error. Reboot, holding "command" and "r" before the Apple logo appears, and then select "disk utility." Repair the disk, and then reboot. Your problem should be resolved.
  5. cfdevkev, Mar 5, 2013
    Last edited: Mar 7, 2013

    cfdevkev macrumors newbie

    Mar 5, 2013
    It is absolutely battery related - I had the exact same problem... same hardware, same symptoms, same everything.

    I would guess your battery is saying to "replace now" (mine was, though no idea if yours will). Either way, I disconnected the battery from the motherboard inside and everything runs just like new. It is a simple connector to remove; iFixit probably has a picture of it if necessary.

    No other solution worked for this -now I am running with "no battery" until a replacement can be ordered.


    Edit: Well, this worked for a short period of time; now back up to near 800% and a useless MBP. Got a battery on order so will see if that does the trick.
  6. megaRa24, Jul 5, 2013
    Last edited: Nov 22, 2013

    megaRa24 thread starter macrumors newbie

    Feb 16, 2013
    @CFDEVKEV - in the meantime I used the macbook without a battery, because at time I use it stationary only anyway. although I had to shut it down and start new (not via 'restart') every 3-4 hours it was at least usable. but it looks like getting worse now (shorter periods of running ok).

    what was your experience after replacing the battery? was everything as good as before? would be nice to hear the ongoing of your story. :)

    EDIT: 22.11.13
    YES, the battery (which blew up a year ago, but was refused to be replaced on warranty by the apple-store, because it happened 3 month after the 12 month warranty) caused the problem. NOW, after the same apple-store replaced the MISSED battery for free, the problem is finally solved.

Share This Page