Some weeks ago I bought a second hand MacBook Air. The MacBook Air runs fine but always shuts down without any warning at around 40-50% in battery mode. After restarting battery is at 0%. First I thought the battery is broken. It was the original battery with ca. 500 cycles. So I bought a new battery and replaced it. But surprisingly the MacBook still shuts down at ca. 40-50%. I tried different things found searching through the internet including SMC reset, NVRAM reset, different OS installations (Sierra, high Sierra, Mojave and also running with a LinuxLive Usb stick), and battery calibration. All of these steps didn't help. So anyone maybe know what could that be? Thank you

2018-10-18 22:01:47 +0200 Sleep    Entering Sleep state due to 'Low Power Sleep': Using Batt (Charge:39%)   

Charge Information:
Charge Remaining (mAh): 735
Fully Charged:  No
Charging:   No
Full Charge Capacity (mAh): 5855
Health Information:
Cycle Count:    6
Condition:  Normal
Battery Installed:  Yes
Amperage (mA):  -927
Voltage (mV):   7586 

System-wide power settings:
Currently in use:
standbydelay         4200
standby              1
halfdim              1
hibernatefile        /var/vm/sleepimage
powernap             0
disksleep            10
sleep                0
autopoweroffdelay    28800
hibernatemode        3
autopoweroff         1
ttyskeepawake        1
displaysleep         5
acwake               0
lidwake              1

UPDATE I just charged the battery (in safe-mode) and the percentage changed from 47 to 100% during one minute...strange

  • your original battery was only half life, they last up to 1000 cycles. – Ruskes Oct 19 '18 at 16:15
  • Applications -> Utilities -> System Information -> Power What does it say about the condition of your Battery? – Ruskes Oct 19 '18 at 16:20
  • Condition: normal – Piotr De Oct 19 '18 at 16:24
  • please post all the numbers – Ruskes Oct 19 '18 at 17:02
  • You have a defective battery, negative amperage means it's drawing current and it shouldn't be. – Allan Oct 19 '18 at 23:00

Verify your Battery information in Applications > Utility > System Information > Power and report the result in your post.


Charge Information:
  Charge Remaining (mAh):   6206
  Fully Charged:    No
  Charging: Yes
  Full Charge Capacity (mAh):   6451
  Health Information:
  Cycle Count:  208
  Condition:    Normal
  Battery Installed:    Yes
  Amperage (mA):    879
  Voltage (mV): 8548

The Charge Remaining (mAh) is the actual % you see. The Full Charge Capacity (mAh) is the health and age indicator, that number goes down over the life. The cycle count is specified up to 1000 cycles. The Amperage (mA) reports the current consumption.

Run pmset -g in Terminal to get System-wide power settings and report the result in your post.

These additional steps may help identify or resolve the issue:

Reset the SMC


Start up in Safe Mode to see if the issue is related to non-Apple startup items, login items, or kernel extensions.

Try to isolate the issue by using another user account.

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