Hardware issue?!

[SC92]

Hi all

 

This morning we've had 4 imacs refuse to boot to the mac partition. At first I thought ok, maybe that partition has corrupted which happens from time-to-time, so 3 of the 4 I have rebuilding at the moment because disk utility couldn't repair each of the partitions. Get to the 4th one & can't boot to the recovery partition at all, odd. Can boot to the Windows partition fine & everything works fine. Can't then boot to the network, so currently can't rebuild this thing. Read a few things online, tried running disk utility through terminal commands remotely to no avail, and booting to safe mode worked the 9th time (Not that I was counting or anything..) but then the keyboard/mouse did not work whatsoever. This is the same keyboard mouse that works fine on the bootcamp part of said machine. Swapped them with known working ones, no joy. I then reluctantly try to network boot again & hurrah, it worked! Wait never mind, keyboard/mouse still doesn't work. Is there anyone that has had anything like this before, I seem to be just going around in circles here & getting nowhere fast!

[Rozzer]

Have you cleared all the partitions and remade them? IF that doesn't work sounds like hard drive failures imo.

 

Ross

[SC92]

Unable to format the whole drive as can't get disk utility booted from either the hdd or recovery partition. It's Lion too so we don't have a disc to format from, even if we were able to boot to disc too! Can't really see what else I can try here

[ste1988]

what happens if you try a snow leopard disk???

[SC92]

Have tried booting from a SL disc, but had effectively given that up after the thing was still trying to load it after at least half hour. Keep the suggestions coming though, might've missed something very simple, it is friday..

[ste1988]

being friday, that was, and is the only thing i can come up with lol. Looking very much like your first thought, and a hardware failure of some sort, did you can out apple care/under warranty still?

[iSteve]

What machine is this?

 

When you say they don't boot from the network / CD / HDD are the machines locking up? If so I would suggest checking or swapping out the RAM. Failing that source (!) and Apple Service Diagnostic CD for your model of machine which will thoroughly test each hardware component to narrow down any hardware issue. If the computer is under warranty, sending it off or taking it to a store will take care of this.

 

You can also boot the machine holding down T to put it in target disk mode. Whilst in this mode connect it to a working Mac with a firewire cable. The drives will mount on the desktop of the working machine and you will be able to run Disk Utility or similar on the bad Mac's disks from the working one.

 

Hope that helps.

[SC92]

What machine is this?

 

When you say they don't boot from the network / CD / HDD are the machines locking up? If so I would suggest checking or swapping out the RAM. Failing that source (!) and Apple Service Diagnostic CD for your model of machine which will thoroughly test each hardware component to narrow down any hardware issue. If the computer is under warranty, sending it off or taking it to a store will take care of this.

 

You can also boot the machine holding down T to put it in target disk mode. Whilst in this mode connect it to a working Mac with a firewire cable. The drives will mount on the desktop of the working machine and you will be able to run Disk Utility or similar on the bad Mac's disks from the working one.

 

Hope that helps.

 

It is a 21" imac, purchased in approx July 2010, so no warranty unfortunately. What I mean by not booting is that whichever I attempt to boot from, about as far as I am able to get is the white screen with the Apple logo & the spinning gear - I have been able to boot into safe mode a few times, but this is rare and even when I am able to, the mouse moves but does not click, nor does the keyboard work.

 

Booting into target disk mode in principal sounds like a great idea but the other 3 machines that did have the same problem before hand the disks were not repairable using disk utility, so had to rebuild. I will give it a go later on though, class in the room now & the bootcamp partition on that same machine still very strangely works, so they are at least able to use that.

 

Where would I go about 'acquiring' a diagnostic cd for that particular machine? Is it something that we can buy?

 

Thanks so far!

[iSteve]

You'd have to have a look "online". It's a service tool so not available to Joe Public. If you have a relationship with the reseller you got the machines from they may be able to help you out.

[SC92]

You'd have to have a look "online". It's a service tool so not available to Joe Public. If you have a relationship with the reseller you got the machines from they may be able to help you out.

 

Luckily, it was actually on my 'Applications' disc that came with the machines - not a bad result. However upon reading up on the hardware test, it doesn't work if you have a firmware password set. Now my problem is being able to remove the firmware password from said iMac.. without the ability to boot into anything at all.

[Marci]

Now for reasons I won’t delve into I have an EFI Firmware password set on my Mac. I presume if your reading this article your the same. The EFI firmware password essentially stops you doing any of the important key combinations at boot, resetting PRAM/NVRAM, single user mode the whole shebang. Now this is useful in many many circumstances except when your screwed like I was. Essentially when I thought I was resetting my PRAM and NVRAM I was doing absolutely nothing. If your as screwed as I was and cannot get to a DVD to boot OR you have forgotten your password there is only one way around it.

 

1.Add or remove a stick of ram. Obviously if you have one stick in, add one and if you have two in remove one.

2.Power on the mac and immediately press and hold command-option-P-R.

3.The system will restart with the ‘bong noise’, allow it to do this 3 times. On the third ‘bong’ you can let go of the keys.

4.The machine will now boot with a cleared password and reset PRAM/NVRAM.

5.You can shut down the machine and replace the original ram configuration.

 

(Source: Bypassing the EFI Firmware Password on a Mac | David J Moore)

S'worth a try *shrug*

[HodgeHi]

The newer macs have diagnostic boot up now built into the EFI firmware. Just hold down D on startup.

[HodgeHi]

Also check the SMART status of the drive. I had one where the mac partition wouldn't boot but windows would. Replacing the HDD sorted it out.

[iSteve]

Luckily, it was actually on my 'Applications' disc that came with the machines - not a bad result.

 

Apple Hardware Test (on consumer CDs) is not the same as Apple Service Diagnostic, but the hardware test will help you out. Glad you're semi-sorted.

[SC92]

Successfully got into the hardware tester, but the quick scan showed that everything was working as expected. Didn't quite believe that so I have set the advanced hardware scan running and I shall check back on it in the morning. Part of me is hoping that it picks something up, so then I can easily replace said faulty part. I am going to be completely stumped if this one comes back clean too!

[SC92]

Extended hardware test came back with no problems. Let the head scratching commence once again.

[ste1988]

Also check the SMART status of the drive. I had one where the mac partition wouldn't boot but windows would. Replacing the HDD sorted it out.

 

Did you check that as well?

[bladedanny]

It's been a few years since I last worked with Macs but resetting PRAM often sorted funny issues, not sure if it's still relevant though. 'CMD + OPT + P + R' after pressing the power button.

 

Like I said it may not be relevant on newer macs.

[HodgeHi]

You could also try resetting the SMC. This differs from machine to machine so you would need to find out on Apple's pages what the process is for yours.

[bladedanny]

You could also try resetting the SMC. This differs from machine to machine so you would need to find out on Apple's pages what the process is for yours.

 

If I remember correctly most iMacs that have no access to the case you can reset their SMC by taking out the power cord and holding the power button for 10 seconds, the same used to apply to laptops.

[HodgeHi]

Laptops also require the battery to be removed as well.

[SC92]

I think I have now sorted this. Resetting the PRAM then allowed me to boot into safe mode, which then after a few restarts I was able to get into Lions recovery hd. Although the drive came back from disk utility as unrepairable, I then tried to erase the partition but couldn't do that either so I have just ended up formatting the whole drive instead of that 1 partition. It is now rebuilding with Deploystudio so fingers crossed it all comes together. Thanks for all the help!