Help with MBP 2016 hangs on boot, Macintosh HD flickers.

satellitea100

macrumors newbie
Original poster
Jan 8, 2020
3
0
I have the following problem: My 2016 Macbook Pro (El Capitan) hangs on boot. The progress bar loads to near completion, after that it stops. The laptop heats up and eventually shuts down.

What I need to do: Recover important data from the partition, then reinstall. No time machine saves are available :(
What I attempted:
1) I booted into recovery partition (Using Command+R) and launched disk utility. On first launch the disk utility app freezes. On second launch it works, displaying only the recovery partition.
2) Reset NVRAM, rebbot and - Using the terminal, diskutil list command I get Macintosh HD partition listed.

HOWEVER! If I run the command again, it is not longer listed. If I try to open disk utility app, its not listed there either. In order to see it again, I have to shut down, reset NVRAM, reboot into recovery mode and run the same command.

I do not understand this flickering behavior.

While I suspect disk failure, I am hoping that its simply an issue with the partition table.
 

satellitea100

macrumors newbie
Original poster
Jan 8, 2020
3
0
Hello, thank you for the suggestion - I do not have another mac, but I ordered a thunderbolt cable in case one shows up!
I wonder however if it will be able to see the partition. I have read somewhere that there is a way to reconstruct the partition with diskutil command line, I want to try that first.

At the mean time, this is what my output of:
Code:
diskutil list
looks like:
(at boot)

-bash-3.2# diskutil list

/dev/disk0 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme +2.1 GB disk0

1: Apple_HFS OS X Base System 2.0 GB disk0s1



/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *121.3 GB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_CoreStorage Macintosh HD 120.5 GB disk1s2

3: Apple_Boot Recovery HD 650.0 MB disk1s3



/dev/disk2 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Macintosh HD +120.1 GB disk2

Logical Volume on disk1s2

415411E3-C54B-44FC-BFE5-DF71AF55E7C1

Unencrypted



/dev/disk3 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +5.2 MB disk3



/dev/disk4 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk4



/dev/disk5 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk5



/dev/disk6 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk6



/dev/disk7 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk7



/dev/disk8 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk8



/dev/disk9 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +6.3 MB disk9



/dev/disk10 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +2.1 MB disk10



/dev/disk11 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +1.0 MB disk11



/dev/disk12 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +2.1 MB disk12



/dev/disk13 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk13



/dev/disk14 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk14



/dev/disk15 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +1.0 MB disk15



/dev/disk16 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +6.3 MB disk16



/dev/disk17 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk17



-bash-3.2#

-bash-3.2#
And when I run the command the second time:

-bash-3.2# diskutil list

/dev/disk0 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme +2.1 GB disk0

1: Apple_HFS OS X Base System 2.0 GB disk0s1



/dev/disk3 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +5.2 MB disk3



/dev/disk4 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk4



/dev/disk5 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk5



/dev/disk6 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk6



/dev/disk7 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk7



/dev/disk8 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk8



/dev/disk9 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +6.3 MB disk9



/dev/disk10 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +2.1 MB disk10



/dev/disk11 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +1.0 MB disk11



/dev/disk12 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +2.1 MB disk12



/dev/disk13 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk13



/dev/disk14 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk14



/dev/disk15 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +1.0 MB disk15



/dev/disk16 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +6.3 MB disk16



/dev/disk17 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: untitled +524.3 KB disk17



-bash-3.2#
 
Last edited:

hobowankenobi

macrumors 65816
Aug 27, 2015
1,040
299
on the land line mr. smith.
If the partition is there and Disk Utility can see it (while in TDM) you try running First Aid through the GUI or CLI if you want.

If it can be seen, you can also run any data recovery tools on it just like any other external HD...assuming it is not encrypted, or you can authenticate to decrypt and access the drive.

Forgot to ask: Did you try Internet Recovery Mode? With cable or at the prompt to join WiFi (These are instructions for an older Mac, will vary a bit):

  • Shut down your Mac.
  • Hold down Command-Option/Alt-R and press the Power button. (On some Mac keyboards the Option key will be named Alt).
  • Hold down those keys until you a spinning globe and the message "Starting Internet Recovery. This may take a while".
  • The message will be replaced with a progress bar. Wait for it to fill. Expect it to take a while...
 
Last edited:
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DeltaMac

macrumors G3
Jul 30, 2003
9,752
2,423
Delaware
I would suggest that trying to rescue your boot drive, from another partition on that same (likely failing) device is probably an exercise in futility (the recovery partition is another partition on your boot drive!)

Boot to an external drive. You can easily install a macOS system on an external drive.
While booted to that external drive, run whatever tools and commands that you want, which will probably be more productive than continuing and failing to get the drive to mount long enough to do anything.
This is also your clue that you should have an external drive that you can at least have a backup, just in case this happens to you again.

final note (and trying not to be redundantly repetitious :cool: ) - a backup drive is NOT a luxury. It is a necessity!
 

satellitea100

macrumors newbie
Original poster
Jan 8, 2020
3
0
Hello,

@hobowankenobi :
Yes, I have tried internet recovery, but with the SSD in, it crashes. It loads fine when I remove the SSD though.

@DeltaMac :
I have tried to boot with the linux install usb, was able to see the Macintosh HD partition, however I was not able to mount it.
Installing HFS toolsdid not help, even though the partition is not encrypted.

As for installing mac macOS system on an external drive, its an interesting idea. Can I install it on a USB?
If so, could you recommend any guide? Do I need to buy a license for a macOS in order to install it on an external drive?

As for backup thank you for the recommendations, I am well aware of how important it is to make backups. The computer belongs to my mother lol. I have told her to do backups several times but she did not listen.
 

DeltaMac

macrumors G3
Jul 30, 2003
9,752
2,423
Delaware
(You don't have to purchase a license, the macOS system has been basically free to use on a Mac for more than 5 years!)
There's only a few steps needed to install a macOS system on an external drive:
Boot to the recovery system.
Plug in the USB drive that you want to use for booting.
You will want to make sure the drive is prepared by erasing that drive with the Disk Utility.
Make sure the format is Mac OS Extended, and that the "scheme" is GUID partition map.
Name the drive something that you like. I suggest that you choose a name that is unique, different from your boot drive.
Erased? Quit Disk Utility, then choose Install macOS. Choose the drive that you just erased (with the new name, remember?) as the destination for the install, and continue with the install. Your system will download the complete install, copying all the files to the fresh drive. It will reboot to finish the install. This might take 30 minutes to an hour, depending on the speed of your internet connection, and also the speed of your external drive. You can then do the new user setup on that external drive. You will then be booted to that external drive, running a basic system, with just the Apple-supplied apps.
And, you can see if your internal drive is mounted on the desktop, where you can view the files and folders on that drive if possible. You can also try Disk Utility, which is in the /Applications/Utilities folder.
Launch Disk Utility. The boot drive on the computer should be listed, original name from Apple would be Macintosh HD, but it might have been changed at some point. If you see that drive listed, you can choose that, then click on First Aid, where you can run a test of the file system. That "First Aid" may report that there are problems on that drive, and might tell you it cannot be repaired, and may also tell you that you need to erase/format the drive, and try the test again. Remember, erase will be your last resort, as you will lose everything that is not backed up.