I have a 2019 15" MBP which has had a string of issues, but is passing all hardware tests when serviced at the Genius Bar:

November 2019–March 2020

Mac freezes daily, usually towards the end of the work day (4–5pm), mouse and keyboard are unresponsive, reboot resolves the issue.

March 2020–September 2020

Mac becomes unusable multiple times during the day due to really high kernel_task CPU usage (sometimes more than 4000% when no apps are open). Reboot does not resolve issue, but turning the MacBook upside down in clamshell mode seemed to help (connected to external display). Some tasks such as a Skype call with video are essentially impossible. Resolved by reinstalling the OS without restoring from back up.


Battery depleting at extreme rate, Mac is extremely hot even upon start up and fans almost always running at full speed. Now the icon in the upper right says "service battery", even though the battery has less than 400 battery cycles.

This just seems to me like there is some fundamental core hardware issue at play that Apple is failing to diagnose.

Has anyone experienced similar, or any insight into what is happening here?

  • The battery might be affected by the heat of CPU, which causes it to degrade. Also, what is the 2nd/3rd most CPU intensive task?
    – Joy Jin
    Commented Sep 20, 2020 at 3:42
  • Also, post the output of kextstat, since this is related to the kernel.
    – Joy Jin
    Commented Sep 20, 2020 at 3:43
  • @JoyJin I checked kexstat at the height of the kernel_task issue and deleted third party kernel extensions, issue still persisted. Now that the issue has resolved by reinstalling OS, I can't really check what the 2nd or 3rd CPU intensive task is.
    – univers_
    Commented Sep 20, 2020 at 23:14

1 Answer 1


High temperature sensors is the only other thing you didn't mention explicitly. Can you correlate this to ambient temperature / inability of the CPU to cool itself (to 80C is cool / even 100C is fine if Kernel Task isn't taking more than one core)?

Barring a clean erase install of the OS fixing this, I would seek repair service.

  • It definitely seems like temperature is the common thread here but I cannot correlate it ambient temperature. I am not keeping a close eye on the actual CPU temps, but during one period of high kernel_task usage (the Mac being almost unusable), the CPU was not even above 80c, yet the actual Mac was extremely hot to touch. I performed a clean install two weeks ago which resolved the kernel_task usage, but now I have this battery issue to replace it. The Genius Bar has already serviced the computer after the clean OS install and cleared it of any hardware issues.
    – univers_
    Commented Sep 19, 2020 at 22:46

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .