George Garside Blog

A place of many ramblings about macOS and development. If you find something useful on here, it's probably an accident.

You can find the previous shutdown cause on your Mac by running the following command in Terminal. It used to be you could use, but as part of the move to unified logging, it’s no longer possible to query backwards with, so you need to use Terminal to find your previous shutdown cause.

log show --predicate 'eventMessage contains "Previous shutdown cause"' --last 24h

If Mac has shutdown in the time specified, you should see messages such as Previous Shutdown Cause: followed by a number. The number is a cryptic shutdown code representing the cause of the shutdown.

Below are a list of shutdown causes on macOS and OS X with a description of the code and explanations for what the codes mean, including some initial troubleshooting steps. The troubleshooting steps are by no means exhaustive, but should give you a good starting point for how to proceed with your investigation, especially if you suffer from the issue repeatedly.

5Correct Shut Down.Shutdown was initiated normally, from the macOS Shut Down menu or other shutdown command such as /sbin/shutdown. This does not indicate an issue with your system.
3Hard shutdown.Check the power button if you did not perform a hard shutdown yourself. It could be the case that the power button stuck down and forced a shutdown.
0Power disconnected.Check power supply/battery on a laptop, or the power supply for a Mac without a battery. On a laptop, the Mac should hibernate before the battery becomes so discharged it is unable to shutdown correctly, therefore if you see this shutdown cause on a laptop it may indicate a hardware issue with the battery or with the battery controller for reading the charge. Try resetting the SMC by connecting the switched off computer to power, holding ⌃control+⌥option+⇧shift and pressing power.
-3Multiple temperature sensors exceeded the defined limit.Hold D on boot to run Apple Diagnostics and follow the instructions if any errors are found. If the issue persists, make an appointment at an Apple Store. For Authorized Service Providers, Run Apple Service Diagnostics to check which sensor went beyond expected thermal limits.
-60Bad master directory block (badMDBErr).Back up your data, erase the disk and reinstall macOS. If you continue to run the system, data loss may ensue. Use Time Machine to keep a backup until you are able to erase and restore. A common symptom is being unable to repair with Disk Utility — as such, erasing the disk is required as mentioned.
-61Watchdog timer detected unresponsive application, shutting down the system.Troubleshoot for stuck application, startup item and any loading preferences. Boot to Safe Mode by holding ⇧shift on boot which disables most startup items and daemons. If the problem does not occur, try a new user account.
-62Watchdog timer detected unresponsive application, restarting the system.The system will automatically restart after this shutdown cause, unlike -61. Troubleshooting applies the same for cause -61. -61 is used where the system believes it cannot automatically recover, whereas -62 is used where the system determines it is likely to be resolved after restart. Hardware acceleration has been experimentally deemed a potential cause, based on kernel extensions being shown in logs. Memory management may be a potential cause, such as Google Chrome’s excessive use of RAM, which can be mitigated with various extensions that suspend tabs when not in use. While it is a bug with macOS that Google Chrome should be able to cause a -62, such mitigations might be necessary.
-63unknownHave you got this error too, or any information? Leave a comment below!
-64unknownHave you got this error too, or any information? Leave a comment below!
-65unknownPotentially linked to operating system issue. Try reinstalling macOS as fresh or booting from clean install on an external drive.
-71SO-DIMM Memory temperature exceeds limits.If possible, swap memory module and check with known-good one to confirm issue is with memory. Check fans physically and with an app such as iStat Menus to determine whether the fans are rotating correctly and being reported correctly. Check air flow: open device and clean airways.
-74Battery temperature exceeds limits.Reset the SMC by connecting the switched off computer to power, holding ⌃control+⌥option+⇧shift and pressing power. Swap battery and check with known-good one to confirm issue is with customer battery.
-75Communication issue with AC adapter.Check power/MagSafe connector (plug), adapter and cable. Make sure the adapter in use is an official Apple power supply. On MacBook Pro with USB-C, connect power to opposite side of laptop to determine if issue is with specific ports.
-78Incorrect current value coming from AC adapter.Make sure the adapter is an official Apple power supply. Check AC adapter plug and cable. Confirm current at the wall where the adapter is connected to.
-79Incorrect current value coming from battery.Check battery statistics: check if cycles are excessive and may indicate the battery needs replacing. Check the battery connection to logic board.
-86Proximity temperature exceeds limits.Check thermal contact with heatsink, fan connection and physical/reported activity.
-95CPU temperature exceeds limits.Check thermal contact with heatsink, fans. Reset SMC by connecting the switched off computer to power, holding ⌃control+⌥option+⇧shift and pressing power.
-100Power supply temperature exceeds limits.Check fans and air flow. Confirm power supply is official Apple. If MagSafe, remove any MagSafe adapters in use (e.g. MagSafe 1 to 2).
-102OvervoltageSafety shutdown related to over voltage protection (MLB or Battery).
-103Battery cell under voltage detected.Check battery and replace with known-good. Perform one charge cycle, then try again.
-104unknownPossibly linked to battery issue. Perform one charge cycle and try D-boot to run diagnostics.
-108unverifiedLikely memory issue. Commonly occurs when RAM is full and there was an issue with paging. Can occur when the system is sleeping.
-112unverifiedMemory issue. Almost always occurs around -128, another memory issue. Almost certainly hardware fault. See -128 for troubleshooting.
-127PMU forced shutdown.Check power button on your hardware. Potentially fine if you forced shutdown, otherwise may be hardware/SMC issue.
-128unknownPossibly linked to memory issue. If the issue is persistent, try replacing the RAM with known-good if your hardware has removable RAM.

Have you got an error not listed, or any other information on an existing one? Leave a comment below and I’ll keep this list comprehensive and up-to-date!

Leave a Reply

8 James Reynolds’s avatar

Nobody seems to know what these codes mean but you. Where did you get this list?

2 tanya e. pfeffer’s avatar

Any thoughts on what -64 represents?

1 Chaitanya’s avatar

For -128 (MBP Mid 2014) Try Ctrl+Cmd+Shit+Esc. Hopefully it will work keeping system stable rather than frequent shutdowns with -128 cause. I experienced the same and from Oct (post installing Catalina) Even downgrading to Mojave didn’t help. Took MBP Apple to Genius Bar. They diagnosed the system throughly and didn’t report or see any issue; hence, ruling out the logic-board/RAM or any other hardware issue for now).

I am assuming previous opened processes (just before are the crash( are not getting purged and causing system failure. I might be totally wrong. Even shutdowns and restarts didn’t help but trying the (Ctrl+Cmd+Shit+Esc) killing all processes followed with normal shutdown, starting system worked for me.

0 chaitanya’s avatar

Correction: Alt+Cmd+Shift+Esc to kill the processes.

And apologies for typos in my initial note.

1 Stamina Bing’s avatar

6 anyone?

1 Boaz’s avatar

same here. a lot of it.

1 Sharath Raju’s avatar

I am consistently getting the -128 error on a mid-2014 MBP (non-removable RAM). Any thoughts/suggestions on how to diagnose?


0 Justin’s avatar

-128 is most common with failing memory. So in your case you would need a logic board replacement since the memory is on board.

0 Chaitanya’s avatar

Interesting, looks like I am observing there is some pattern here.I also mid 2014 MBP. And I also started getting this since last week of Oct 2019 (post installing Catalina this has become more). Down grading to Mojave didn’t help. Took two months for me to observe there is an issue as the system shutdown intermittently.

Recently went to Genius Bar, they diagnosed it and mentioned all good with my MBP and couldn’t trace the exact issue/cause. Assume some occupation. (I also have Mac Air which have same Catalina installed using Time machine and it is working normal and good.)

Give a try for the below. Hopefully, it will not crash so frequently. Press Ctrl+Command+Shift+Esc : to kill all the processes. Me doing this stopped issue at least for certain time. Otherwise, it is horrible to use the system. Assuming there are some processes that are obsolete and system is not able to recover from it and shutting down. Even restarts and shutdown didn’t help and keeps occurring, until you kill them in this manner and start again. Good luck. Let me know if helps.

0 chaitanya’s avatar

Correction: Alt+Cmd+Shift+Esc to kill the processes.

And apologies for typos in my initial note.

0 Springer55’s avatar

I started to get the -128 issue on a fresh install of Catalina, too.

1 stephen boyle’s avatar

not sure if anyone is watching here – but ive been trying to build a script that keeps track of previous shutdown causes for our records. this is working great and i love the description above — but does anyone have weird behavior on their machine not always logging 5?? for example if i restart my laptop which is working fine it seems to always log a 3. although i was testing this out and previously had done a bad restart. the only way i can get back to 5 is to shutdown and start up again. another machine i have tested on has logged a 0 when it was a normal reboot too… i just wonder how accurate apple treats these.

0 Kev’s avatar

Okay so I get repeated -63 on 2018 Mbp.

0 Anders’s avatar

Getting the -63 too. Any help on what this issue can be would be awesome.

0 anders’s avatar

Also getting repeated -63 on 2018 – any tips would be helpful

0 Karntchana Sangjan’s avatar

Could be T2-related kernel panics. Check kernel logs to confirm.

0 Christian’s avatar

I got the shutdown cause -11. Any idea, what this means?

0 Nath’s avatar

Has anyone seen “Previous shutdown cause: -1”?

0 Dan’s avatar

Anyone knows about -20 cause?

0 LuxoNum’s avatar

I’m having that exact issue, but I’m not sure but I think It may be a kernel panic though

0 Al’s avatar

Hi, in Catalina I have ” Previous shutdown cause: 1 “.

Never seen 1. Anyone know what it means?


0 raul’s avatar

ia have a -102

any ideas?

0 Karan Bansal’s avatar

Anyone knows about -59?

0 Griffin’s avatar

Getting -59 as well on 2018 MacBook Air 10.14.6. No clue. Very annoying. It happens every time i put it to sleep by closing lid. I have to power it back on manually and previous shutdown cause is -59.

0 GGSS’s avatar

I’m getting cause -40, after a bunch of -128. Don’t know what it is.

0 Alex99’s avatar

What is the shutdown code «-5» means? I’ve got code -5 instead of 5. My mac just shutting down randomly without a reason! Please help

0 Ethan Cho’s avatar

What is Cause -11 ? I have a macbook pro 2019, shutdown cause -11 happened 5 times today!

0 Vic’s avatar

I’m getting a lot of cause -20 and -11. This is on a 2018 Macbook Air. Any suggestions to these new causes? I can’t find them anywhere.

1 Vic’s avatar

Today I got a cause: 1 also….

0 Dan’s avatar

1 comes up for me if I did a restart instead of a shutdown. But only on Mojave

0 Rino Armadiaz’s avatar

Hi George,

I’m having a random restart with my MacBook Pro 13″ 2018 and the logs says im having “shutdown cause : -20”

i searched on google seems very few people are getting the same problem.

Do you have any idea what the problem is? thanks!

0 mk’s avatar

I also have the code of -20. But it says here in my mbp 15 2019. Bad ‘cos I just got it.

0xcf Default 0x0 0 0 kernel: (AppleSMC) Previous shutdown cause: -20

Could it be SMC?

0 LuxoNum’s avatar

I think this may be a T2 chip issue because my MacBook Air 2018 is having the same code display and I’ve only seen 2018 or 2019 MacBooks with this issue in this comment section