Question iMac (2011) will not boot; Grey screen

[MrTuRtLe03]

Firstly, I feel slightly ashamed and took a big hit to my ego posting to a Mac sub-forum here. Apple and I do not get a long at all, but I digress. I received an iMac that got a new keyboard that wasn't working, so I rebooted and *BAM* the keyboard worked. Magic right? Then I rebooted again, and suddenly the iMac was stuck on a grey screen with the Apple logo and the spinning gear.

Steps I have tried:
- Rebooting again (duh)
- Attempting to boot into Safe Mode (didn't work. Totally a WTF moment..)
- Attempted to boot to install CD (Same thing, stuck at Apple w/ spinning gear)
- Reset the NVRAM + SMC
- Ran FSCK from Single User Mode (SUM) - something about the B tree being rebuilt. It then said that it appeared okay, might try it again.
- Ran diagnostics with the Applications CD (by pressing D) It booted and passes the extensive test
- Whispered and tried to coax it to work. It wouldn't respond...
- Pulled the HDD and right now I am backing it up from my PC
- Still will not boot the CD with the HDD pulled
- Right now I am downloading DiskWarrior

Any ideas? Anything would be helpful, the HVAC business (that gave me the iMac to work on) really needs it back to print off Tax things.

Thanks so much in advance!

 

[Ijack]

If it's still not working after what you have tried then I'd have to say that it is beginning to sound like a hardware fault (despite the diagnostics). There is a thread here: http://macosx.com/forums/mac-os-x-system-mac-software/318328-imac-completely-froze-wont-boot-install-disc-help.html about a similar (not identical) fault where it is suggested that a full hard disk could cause symptoms like this. In that case - if you have access to another Mac - you could use target mode via firewire to get the data off the disk and/or free up some space on the disk.

Not a particularly helpful answer, I realize, but you appear to have tried all the normal Mac troubleshooting steps without success.

 

[MrTuRtLe03]

If it's still not working after what you have tried then I'd have to say that it is beginning to sound like a hardware fault (despite the diagnostics). There is a thread here: http://macosx.com/forums/mac-os-x-system-mac-software/318328-imac-completely-froze-wont-boot-install-disc-help.html about a similar (not identical) fault where it is suggested that a full hard disk could cause symptoms like this. In that case - if you have access to another Mac - you could use target mode via firewire to get the data off the disk and/or free up some space on the disk.

Not a particularly helpful answer, I realize, but you appear to have tried all the normal Mac troubleshooting steps without success.

Well you sir have provided more help than Apple forums - the only response there was to bring it to a 'Professional Mac-Certified repair tech'. Yes the problem is similar, but when I pulled the drive there is only 111gb of the 1tb drive in use. I also ran a battery of diagnostics on the drive after I pulled it from the iMac itsself and it will not fail. I even set it to look for 12+ hours and it encountered no error. Quite odd. Right now I am trying to burn DiscWarrior and am praying that it will work. I have a suspicion that the Mac OS install disk is bad - but I do not have another to test this on.

 

[Ijack]

If the disk has tested OK then I would incline even more to the possibility of a fault on the motherboard - possibly with the disk controller. Otherwise it doesn't seem logical that the computer won't boot from the install CD with the hard disk removed.

Are you using the original install disk that came with the Mac? Macs are pretty specific about which install disks they will work with. It has to be the exact one supplied with the computer or else a retail disk. One other thought - do you have an external disk enclosure that you could put the disk in? A Mac should happily boot from an external USB drive so that might be another test to do.