macbook suddenly won't start, no diagnostic access

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macbook suddenly won't start, no diagnostic access

So the macbook rebooted suddenly without any good reason. It went into a reboot loop.

Now it starts, logo appears, bar moves across. Screen goes grey. That's it.

Since then I have tried all the startup keys. Some of them alter the sequence of logo and bar very slightly but none of them get me beyond the dreaded grey screen. The only one interesting was the internet recovery (option command R) which got me to the spinning globe and bar. However at the end of that very long bar the screen again went grey and the fans started running on full. I'm about to try making a bootable USB but my hopes are understandably very low.

Second hand 2011 macbook but visibly in very good condition, surprised something would suddenly pop without warning. I'm guessing this is the death of something important on the logic board.

MacBook Pro, Mac OS X (10.7.5)

Posted on Jan 31, 2016 6:22 PM

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Answer 1

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my ginger

Level 5

4,904 points

Jan 31, 2016 11:16 PM in response to Technical Slave

What options have you tried other than command r. Safe mode ,start with shift key? Single user command s? Start with option key held down? Should show the startup drive and the recovery volume. Have you done a pram reset? https://support.apple.com/en-us/HT204063 SMC reset. https://support.apple.com/en-us/HT201295 In single user you will get command line. When it stops loaning you can run (fsck -fy), without parentheses. Hit enter. If it comes back modified, run again till is says ok. Then type reboot. Hit enter.

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Answer 2

Feb 1, 2016 12:44 AM in response to my ginger

thanks for the response!

I made some progress since writing earlier. I had in fact not tried all the startup keys and a lot of them were useful (ahem. may have been a bit hasty there).

Option D got me to the internet hardware test. The hardware passed the short test. Didn't run the comprehensive test.

I was able to run the hardrive as an external disk connected to another computer. Backed up a lot of the data.

Option key alone doesn't show up any recovery partition. However I tried using a thumb as an osx booter. It recognized the drive but after that I just got a progress bar leading to a grey screen. (haven't tested the thumb as a boot drive on other computers yet).

I reset the NVRAM. Was rewarded with a bit of colourful static but then back to the grey screen.

Command S gets me into single user and a screen or two worth of code. There seems to be some error messages here and there but not sure how important they are or what they mean.

Double checked shift key - can't get into safe mode, just boring old grey screen.

Haven't tried fsk just looking up what that does.

Any help appreciated.

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Answer 3

my ginger

Level 5

4,904 points

Feb 1, 2016 9:00 AM in response to Technical Slave

Using fsck -fy is a command line to repair the hard drive. It's like running repair in disk utilities. In single user one of the last lines should have that command. But you have to type and run it to get it to attempt a repair. Modified would mean, found errors. If you thumb drive is an installer, it should have as part of the install an option to run disk utilities. See if you can boot the drive running it as an external disk to your MBP. If you can, then you may have a bad internal drive cable.

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Answer 4

Feb 1, 2016 4:00 PM in response to my ginger

Fsck doesn't show any errors - "volume appears to be ok". It won't boot from the thumb but it runs smoothly as an external disk. It may be a bad internal drive cable - how would I diagnose that? Also I'm thinking this could be a GPU problem? This is a 15" 2011 mbp, apparently known for such things. I'm just about to run the extended internet apple hardware test. Do you think that would correctly find a bad GPU?

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Answer 5

my ginger

Level 5

4,904 points

Feb 3, 2016 9:44 PM in response to Technical Slave

Running the hardware test would not hurt. But that is not definitive. The only way to check if it is a GPU problem is to take it in to the apple genius bar to have it tested. If you can run your operating system with no problems from an externally mounted drive, then most likely the internal cable is the problem. https://www.apple.com/support/macbookpro-videoissues/

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