NZ Eve

Q: 2011 iMac powers off during startup in all modes

Specs:

iMac (Mid-2011) 2.5GHz Core i5 1TB (SSHD) 12GB (RAM)

Running OS X 10.10. Yosemite

 

I was having trouble uninstalling some programs (Adobe CC items, for whatever relevance that may be) so restarted my machine in Safe Mode, thinking my re-installation tasks may be more cooperative in Safe Mode.

I'd expected a Safe Mode boot to be slower than usual, but this was inordinately slow...and then at the near-halfway point of the status bar, the machine shut down (didn't auto-restart).

I tried Safe Mode boot again. Same thing happened.

I reset NVRAM, and tried to boot normally...but the same thing happened — both the excessively slow progress bar, and shutting down halfway through.

I tried booting from Recovery HD, but it made no difference—I still had a slow progress bar, and the machine shut down halfway through.

I ran fsck -fy in Single User mode. Results:

 

** /dev/rdisk0s2

** Root file system

Executing fsck_hfs (version hfs-285).

** Checking Journaled HFS Plus volume.

The volume name is Macintosh HD

** Checking extents overflow file.

** Checking catalog file.

Incorrect number of thread records

(4, 25319)

** Checking multi-linked files.

** Checking catalog hierarchy.

** Checking extended attributes file.

Incorrect number of extended attributes

(It should be 502461 instead of 502462)

** Checking volume bitmap.

** Checking volume information.

** Repairing volume.

** Rechecking volume.

*** Checking Journaled HFS Plus volume.

 

[...this repeats as previously, with same errors, three times. Then:]


** The volume Macintosh HD could no be repaired after 3 attempts.

*****The volume was modified*****

 

What next?

iMac

Posted on Jan 19, 2016 11:16 PM

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Q: 2011 iMac powers off during startup in all modes

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  • Helpful answers

  • by Mike Sombrio,

    Mike Sombrio Mike Sombrio Jan 20, 2016 3:34 AM in response to NZ Eve
    Level 6 (17,234 points)
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    Jan 20, 2016 3:34 AM in response to NZ Eve

    It's likely that your hard drive has failed. Hopefully you have it backed up. Make an appointment and take it in for service.

  • by NZ Eve,

    NZ Eve NZ Eve Jan 20, 2016 9:38 AM in response to Mike Sombrio
    Level 1 (0 points)
    Jan 20, 2016 9:38 AM in response to Mike Sombrio

    There's no other probable scenario? The hard drive is new, freshly installed a few weeks ago.

  • by Mike Sombrio,

    Mike Sombrio Mike Sombrio Jan 20, 2016 2:01 PM in response to NZ Eve
    Level 6 (17,234 points)
    Apple Watch
    Jan 20, 2016 2:01 PM in response to NZ Eve

    By whom? Sounds like a bad hard drive to me. Run the Apple Hardware Test Using Apple Hardware Test - Apple Support Run it 2-3 times in extended mode and see if it reports anything.

  • by NZ Eve,

    NZ Eve NZ Eve Jan 20, 2016 5:43 PM in response to Mike Sombrio
    Level 1 (0 points)
    Jan 20, 2016 5:43 PM in response to Mike Sombrio

    I had the drive replaced by a local mac repair company which, although not an official Apple affiliate, is the only Apple repair guy in town.

     

    Before I saw your latest message, I'd moved the computer next to the router to connect by LAN cable, and found it would boot to RecoveryHD that way. I reformatted the disk (I have an external Time Machine backup, but every time I've migrated it to a machine it seems it hasn't taken long for problems to follow), but on restart it found no startup disk.

     

    I had set it to reinstall an operating system from Recovery HD (it's Lion, which is a pain because I had Yosemite before, but Lion's all Recovery HD would allow me), but it looked dubious. It was still 'downloading additional components' after seven hours, and even though the progress bar looked to have reached the end, when the minute countdown got down to 8 or 5 minutes to go, the time estimation will jump back to about 1 and a half hours. Over and over again, ad infinitum...

     

    I did a force shutdown, at this time reboot didn't respond to RecoveryHD keys, nor to the Apple Hardware Test key on the next forced re-boot—both attempts gave me the no-startup-disk-found flashing folder symbol. (LAN was still plugged in.)

     

    I switched to wired keyboard. Apple Hardware Test still wouldn't run, but RecoveryHD would. Now I'm again attempting Lion install, not because I expect it to work, but because I feel better just doing something.

  • by Mike Sombrio,

    Mike Sombrio Mike Sombrio Jan 20, 2016 6:56 PM in response to NZ Eve
    Level 6 (17,234 points)
    Apple Watch
    Jan 20, 2016 6:56 PM in response to NZ Eve

    You're using Internet Recovery and it's slow. If that hard drive isn't dead I'm going to be very surprised.

  • by NZ Eve,

    NZ Eve NZ Eve Jan 21, 2016 1:34 PM in response to Mike Sombrio
    Level 1 (0 points)
    Jan 21, 2016 1:34 PM in response to Mike Sombrio

    I left it overnight.

    In the morning I came back to see it powered down. Booted into Recovery, to Disk Utility window. No Startup Disk was listed in the menu.

    Restored system from Time Machine backup, so I'd at least be allowed an OS to work with.

    Ran AHT advanced, twice (couldn't get to it via D key, but worked via Option-D). First returned error ‘4MEM/9/40000000: 0x88a62a98', the second time returned error '’4MEM/9/40000000: 0x88ed0998'.

    Rebooted in RecoveryHD, ran Verify Disk, which was reported okay. Startup Disk 'Macintosh HD' now detected.

    Rebooted as normal from Macintosh HD. Symbols on startup screen sporadically alternating between apple, and slashed circle.

    Force shutdown.

     

    I wonder if the Apple repair shop will buy the machine off me. At this point, I loathe it, and want nothing more to do with it. It's an unsustainable cost to keep taking it back in for repairs because something screws up within one or two days of his saying it'll be fine for years. The way costs are heading, I may as well have bought one new. Buying refurbished from a Mac repair shop was meant to be a strategic cost-saving move. But I rue it. I RUE IT!

  • by Mike Sombrio,

    Mike Sombrio Mike Sombrio Jan 21, 2016 2:22 PM in response to NZ Eve
    Level 6 (17,234 points)
    Apple Watch
    Jan 21, 2016 2:22 PM in response to NZ Eve

    That's a memory error, bad, unseated or incompatible ram more than likely. That iMac originally probably came with 4Gb of ram and 8Gb has been added at some point. Take out the two 4Gb modules and see if anything changes. Although I've never personnaly seen ram cause a Mac to act like that I suppose it's possible that it's not passing the POST and just shuts down.

  • by NZ Eve,

    NZ Eve NZ Eve Jan 21, 2016 6:53 PM in response to Mike Sombrio
    Level 1 (0 points)
    Jan 21, 2016 6:53 PM in response to Mike Sombrio

    I took the two added 4GB modules out and ran AHT again. The test got a lot further this time, before giving me the error code 4SNS/1/40000000: TH00-9.000.

     

    The town's Mac doctor had told me that fans always run louder when a hard drive is replaced with a non-Apple one, so if that's what the error's about, there's no surmounting it, is there? The AHT has just stopped whenever it's found an error, so does that mean I can't scan for any other hardware abnormalities, if the above will always be present?

     

    (I also want to take this moment to thank you for the time you've spent offering your assistance thus far. I appreciate it!)

  • by NZ Eve,

    NZ Eve NZ Eve Jan 21, 2016 7:10 PM in response to NZ Eve
    Level 1 (0 points)
    Jan 21, 2016 7:10 PM in response to NZ Eve

    Also, when attempting to boot normally after removing the extra RAM, I still get the slashed circle symbol on the startup screen.

  • by Mike Sombrio,

    Mike Sombrio Mike Sombrio Jan 22, 2016 3:57 AM in response to NZ Eve
    Level 6 (17,234 points)
    Apple Watch
    Jan 22, 2016 3:57 AM in response to NZ Eve

    That error is for the hard disk temp sensor. The "Mac doctor" is correct that non OEM hard drives will lack the internal temp sensor that controls the fan but he should have installed an inline temp sensor in it's place. If you ever get it running you can use software HDD Fan Control to control the fan but it isn't the best solution.

    About the screens you see when your Mac starts up - Apple Support

    In my opinion your "Mac doctor" owes you to get the Mac running. He replaced the hard drive and I believe its faulty, he needs to make that right.

    Are you SURE there isn't an AASP near you that you could use instead? https://locate.apple.com/country