MacBook air won't boot after kernel panic

0007776

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I was Using my computer normally, and it suddenly kernel panicked on me. I turned it off using the power button, and then when I tried to turn it back on, it got to the grey screen, but wouldn't go any farther. I then tried to boot it up in safe mode, but after 5 or 10 minutes it hadn't gone much farther, so I tried turning it off with the power button again and restarting it. Now it won't turn on at all, I'll see a black screen, and the sleep light will come on but it won't boot. Anybody have ideas of what to do? It's a rev b MacBook air, 1.83ghz, with 128gb ssd if that matters. Also, Im away from home where the disks are, so I have no acess to disks for the next 3 months.
 

bcaslis

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Mar 11, 2008
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Shut down completely and then hold down the option key and see if your SSD shows up. If so, then it thinks it's bootable. Select it and see if it starts. If it doesn't show up then the disk is no longer bootable. If you can't get the option screen to come up then you likely have a hardware failure.
 

0007776

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Shut down completely and then hold down the option key and see if your SSD shows up. If so, then it thinks it's bootable. Select it and see if it starts. If it doesn't show up then the disk is no longer bootable. If you can't get the option screen to come up then you likely have a hardware failure.
Thanks, I just tried that, and I can't get any screen right now, if I hold down option, the sleep light comes on, and then it goes off again. If i don't, the sleep light comes on, but I don't see any screen, or hear the boot chime. The sleep light stays on, and I can hear the fans until I shut it down, but I see nothing on the screen. So I guess it's a hardware failure then, unless someone else has ideas?
 

halledise

macrumors 65816
Thanks, I just tried that, and I can't get any screen right now, if I hold down option, the sleep light comes on, and then it goes off again. If i don't, the sleep light comes on, but I don't see any screen, or hear the boot chime. The sleep light stays on, and I can hear the fans until I shut it down, but I see nothing on the screen. So I guess it's a hardware failure then, unless someone else has ideas?
try this:

reset SMC
reset NVRAM
if no response: try starting up from install stick (hold down 'c' on startup)

repair permissions - using disk utility
restart normally.


if you do get some action after resetting SMC and NVRAM try the following sequence:

in Terminal:
(copy and paste one command at a time, the 2nd and 3rd take a little while to execute)

sudo chown root:admin /
(now you'll be asked to enter your system password)

sudo kextcache -system-prelinked-kernel

sudo kextcache -system-caches
 

0007776

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I tried the SMC and NVRAM key combinations. Neither worked, and I can't try the restarting from the disks because I'm away from home for the next 3 months and the disks are at home.
 

0007776

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or have it mailed to you … …
I'm in Eastern Europe, and if I had them mailed they would dissapear in customs, I don't trust the postal service or customs agents here at all.
However I did try calling Apple, but while I was on the phone with them I tried starting it up and it started up fine. So I got off the phone, then it froze up and it's not starting again.

Edit: it's working again, and it has been for a little bit longer this time. Anybody got an idea of how to tell if there is some hardware problem that caused it, or if it's just some weird software issue?
 
Last edited:

0007776

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if you do get some action after resetting SMC and NVRAM try the following sequence:

in Terminal:
(copy and paste one command at a time, the 2nd and 3rd take a little while to execute)

sudo chown root:admin /
(now you'll be asked to enter your system password)

sudo kextcache -system-prelinked-kernel

sudo kextcache -system-caches
So I finally got the SMC reset to work, and it results in me being able to access the computer for anywhere between 5 minutes to several hours before it crashes again, I haven't got another kernel panic though it just freezes up and becomes unresponsive. So I'm thinking of trying those terminal commands the next time it starts up, but what exactly do they do?
 

chrisperro

macrumors 6502
Oct 24, 2009
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So I finally got the SMC reset to work, and it results in me being able to access the computer for anywhere between 5 minutes to several hours before it crashes again, I haven't got another kernel panic though it just freezes up and becomes unresponsive. So I'm thinking of trying those terminal commands the next time it starts up, but what exactly do they do?
I know this is old but I'm having the same problem.
What happened? Did you resolve the problem?
Thanks
 

0007776

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I know this is old but I'm having the same problem.
What happened? Did you resolve the problem?
Thanks
If I remember correctly it fully died soon after this thread and had a logic board replacement under warranty that got me another year or so out of it before the battery died and I replaced the computer as it was no longer under warranty.