Model A1225 / Mid 2007 and Early 2008 / 2.4, 2.8, or 3.06 GHz Core 2 Duo processor

441 Questions View all

No boot from any device (DVD, HDD, etc.)

Dear all:

Thank you for having this forum fully working.

My iMac 24" Aluminium (november 2008) can't boot, completely frozen, although all HW are perfectly working.

I'll try to explain the issue best I can.

SYMPTOMS

- After a chime... grey screen of death without Apple's logo.

- No bootable devices detected (either HDD or DVD), when you hold ALT (Option) while booting.

- No way to force boot from DVD.

CAUSE OF PROBLEMS

a) HDD has 3 partitions created by DiskUtils:

/dev/disk0s2= Mac OS(HFS+)

/dev/disk0s3= Linux DVD Installer (FAT32)

/dev/disk0s4= User Data(HFS+).

b) rEFIt installed and fully working on the system ( http://refit.sourceforge.net/ )

c) Linux DVD installer partition was filled this way:

dd if=/path/to/linux.iso of=/dev/disk0s3

As you can see, there are no HW errors at all, everything was perfectly working before dumping the Linux iso into FAT partition.

TEST BED

In the process of dealing with iMac booting problems I organized a test bed which allow to detect where the booting is failing:

STAGE 0 - Setting initial boot memory conditions.

STAGE 1 - Reset NVRAM memory to factory defaults.

STAGE 2 - Booting from external device.

STAGE 3 - Reinstall iMac firmware.

STAGE 4 - Hardware intervention.

Before running the test bed:

a) Unplug all devices except USB keyboard (no wireless keyboard, no mouse... you can plug an USB mouse once you see the graphical user interface up and running).

b) Combination of keys available on booting:

http://support.apple.com/kb/ht1533

STAGE 0 - Setting initial boot memory conditions

This bundle of tests must be executed before any test of next stages.

TEST 0.1 - Erasing booting memory values.

Leave the iMac disconnected from all wires (especially power cord) for 15 minutes for memories to loose their values.

http://www.youtube.com/watch?v=JId524890....

TEST 0.2- Resetting PRAM memory.

a) Press Power button

b) Press CMD+ALT+P+R keys while black screen, before you hear the chime.

c) Hold these keys until you hear 3 chimes (3 reboots).

http://support.apple.com/kb/ht1379.

STAGE 1 - Reset NVAM memories to factory defaults.

TEST 1.1 - Validate machine with Apple's Hardware Test.

=> Detect Hardware errors with Apple's Hardware Test

a) Original Apple's Installation DVD on the machine

Installation DVD should show something like this

DISC 1

Mac OS version 10.5.4

AHT version 3A152

Disc version 1.1

2Z691-6304-A

To use Apple Hardware Test, hold down the D key as the computer starts up.

b) Holding Down D key as the computer starts up

http://support.apple.com/kb/HT1509.

=> Hardware OK: continue with Stages 1, 2 and 3

=> Hardware Failure: jump to Stage 4 (skip Stages 1, 2 and 3)

=> Unable to run Apple's Hardware Test: jump to Stage 3, firmware restoration

TEST 1.2 - Change RAM Configuration: amount or disposition.

a) Open RAM Slot

b) Extract RAM stick from Slot.

c) If you only have one RAM stick, reintroduce it in the unused empty slot of memory.

TEST 1.3 - Resetting PRAM memory.

Please check TEST 0.2

STAGE 2 - Booting from external device

TEST 2.1 - Boot from DVD.

a) Introduce Apple's Mac OS original DVD on the unit.

b) Run Test 0.1 and Test 0.2

=> Force DVD as Booting Device.

c) Press power button.

d) Press C key while black screen, before you hear the chime.

e) Keep hold the C key until you see the MacOS installer window.

http://support.apple.com/kb/ht1533

=> If still no boot from DVD: StartUp Manager with DVD inside the machine.

c) Keep hold Power Button 10 seconds to reboot the machine.

d) Press ALT key while black screen, before you hear the chime.

e) Keep hold the ALT key until you see the StartUp Manager.

f) From StartUp Manager, choose DVD as booting option.

https://discussions.apple.com/thread/138...

=> If still no boot from DVD: StartUp Manager without DVD inside the machine.

c) Keep hold Power Button 10 seconds to reboot the machine.

d) Press F12 key while black screen, before you hear the chime.

e) Keep hold the F12 key until DVD is spelled from the iMac.

f) Run StartUp Manager again (see steps above) .

g) Insert Apple's Mac OS DVD on machine while StarUp Manager is running.

h) From StartUp Manager, choose DVD as booting option.

https://discussions.apple.com/thread/138...

TEST 2.2 - Firewire cable and Target Mode: run installer from external Mac.

http://forums.macrumors.com/showthread.p...

TEST 2.3 - Remote Installation.

You can run this test twice: remote installation from PC and MAC.

=> Remote Installation Server on PC/MAC:

a) Mac OS DVD on PC/MAC optical drive

b) Install Network Client (just run setup.exe from DVD and follow the steps until everything is installed).

c) Keep open a window saying... machine is ready for Remote Install.

=> Physical Direct Network Connection between Remote Installation Server and iMac

a) Unplug power cord from iMac for 15 minutes.

b) Connect to the Server Machine this way:

Option 1.- Crossover Ethernet wire direct connection,

Option 2.- Using an Ethernet switch with no additional devices plugged to the switch.

=> StartUp Manager on Client

a) Run Test 0.1 and Test 0.2

b) Press power button.

c) Press ALT key while black screen, before you hear the chime.

d) Keep hold the ALT key until you see the StartUp Manager.

e) From StartUp Manager, choose NetInstall as booting option.

http://support.apple.com/kb/PH6450

TEST 2.4 - NetInstall.

=> Prepare NetInstall Mac OS NetBoot Server

Option 1 - Using Mac OS X Server

http://support.apple.com/kb/HT4178

Option 2 - Using Linux Server

https://docs.math.osu.edu/linux/how-tos/...

=> Force Boot from the Network

a) Run Test 0.1 and Test 0.2

b) Press Power Button.

c) Press N key while black screen, before you hear the chime.

d) Keep hold the N key until you see the Mac OS X Installation screen.

=> If no NetBoot after 15 minutes: NetBoot from StartUp Manager

a) Keep hold Power Button 10 seconds to reboot the machine.

b) Press ALT key while black screen, before you hear the chime.

c) Keep hold the ALT key until you see the StartUp Manager.

d) From StartUp Manager, choose NetInstall as booting option.

TEST 2.5 - Apple's Mac OS Installer/Reparation from External USB HardDrive.

Very unlikely to work.

=> Create Bootable OS X USB device

a) Format HDD with GUID partition.

http://support.apple.com/kb/PH7247

b) Fill the partition with the Mac OS X installer (only the version your iMac came with, no newer, no older).

=> Boot iMac from USB device

http://support.apple.com/kb/HT1948

STAGE 3 - Reinstall/Repair iMac Firmware

TEST 3.1 - Using Firmware Reinstallation CD.

a) Download and burn Firmware Restoration CD for your iMac

iMac 8,1: http://support.apple.com/kb/TA24012

b) From power off state, press the power button and continue to hold it down until the "Sleep" LED blinks rapidly three times, then slowly three times, then rapidly three more times... this could be chimes, instead of LED blinks! Keep the power button pressed down.

c) Insert the Firmware Restoration CD you have burned into the iMac's CD drive, then release the power button.

d) Monitor the "Progress Bar" beneath the Apple logo as the restoration process updates your iMac's firmware, taking care not to disconnect the power, shut down your computer or restart your computer (otherwise, you will have to start over). The iMac will restart automatically once the firmware restoration is complete.

TEST 3.2 - Using Apple's Propietary Software.

Contact Apple's Technical Support to know the price.

STAGE 4 - Hardware Intervention

TEST 4.1 - Replace the faulty Hardware on your own.

a) To detect faulty Hardware, please run Test 1.1

b) Replace the Hardware following those instructions:

http://www.youtube.com/watch?v=3w6E2_Xqa...

TEST 4.2 - Contact Apple's Technical Support.

Answered! View the answer I have this problem too

Is this a good question?

Score 1

Comments:

What CD/DVD are you using to boot from? Original disks that came with the system, bought OS-X DVD, or your own creation.

by

Have you tried a bootable OS-X USB thumb drive (verified to work on another system)?

by

Thanks for the quick answer. DVDs are Apple's original ones (all of them). It is very likely to be a firmware problem.

by

Why do you think it's a firmware problem? Did you do some poking around in the BIOS altering things? iMac's tend not to have these type of issues as they are a closed architecture (unlike a Windows PC or the Mac Pro).

by

Hi Dan.

The testing sequence should be this way:

Stage 1 - Check all external booting possibilities:

1.1.- CD/DVD with Apple's Original DVD

1.2.- USB with Apple's original restoration tool.

1.3.- NetInstall from Mac device

1.4.- NetINstall from Windows

1.5.- Firewire from Mac device

Stage 2 - Firmware intervention... now back to Stage 1.

Stage 3 - HW intervention... now back to Stage 1

At this point of the Stage 1, only 1.3 and 1.5 trials are missing, since I don't have additional Apple's device. Therefore I should continue Stage 2, firmware intervention.

Since the BootConsole (ALT on boot) do not work at all, it is very likely to be the firmware.

Apple's technical support has two different ways to restore the firmware when the machine comes for reparation:

1.- Propietary SW to reinitializate locked/corrupt firmware, based on machine's ID specific.

2.- CD Firmware restoration.

At home I can only proceed with the method 2: Firmware restoration CD.

So, this is my option.

by

Show 3 more comments

Add a comment

3 Answers

Chosen Solution

From the sounds of it your boot blocks are messed up so the OS can't load. The fact you are getting the system to get as far as you have proves your hardware is OK.

Hopefully you have everything backed up. I suspect you'll need to scrub the disk down and re-partition and format the volumes. Remember the first volume will be a hidden volume for OS-X Lion or Mountain Lion recovery (if your going that way). The first visible volume needs to be OS-X, then you could add in your other OS's.

Was this answer helpful?

Score 1
Add a comment

The testing sequence should be this way:

Stage 1 - Check all external booting possibilities:

1.1.- CD/DVD with Apple's Original DVD

1.2.- USB with Apple's original restoration tool.

1.3.- NetInstall from Mac device

1.4.- NetINstall from Windows

1.5.- Firewire from Mac device

Stage 2 - Firmware intervention... now back to Stage 1.

Stage 3 - HW intervention... now back to Stage 1

At this point of the Stage 1, only 1.3 and 1.5 trials are missing, since I don't have additional Apple's device. Therefore I should continue Stage 2, firmware intervention.

Since the BootConsole (ALT on boot) do not work at all, it is very likely to be the firmware.

Apple's technical support has two different ways to restore the firmware when the machine comes for reparation:

1.- Propietary SW to reinitializate locked/corrupt firmware, based on machine's ID specific.

2.- CD Firmware restoration. At home I can only proceed with the method 2: Firmware restoration CD. So, this is my option.

Was this answer helpful?

Score 0

Comments:

Revew the following Apple TN: Startup sequence and error codes, Here's another more detailed description from another source Peachpit-Macintosh Reference Guide.

As to EFI, there's a lot of confusion as Apple's version is heavily modified. Here's a small writeup on it: review last section.

I still don't think you have a firmware issue here. I still suspect you have corrupted boot blocks and the installed Mac OS is likely corrupted as well, your description of how far into the boot cycle implies this. As to why your DVD is not working is related to the fact the system IS seeing the HD and expects it to load (which it can't).

How to fix this: Hopefully you have a spare HD that will work with your system (older SATA I or SATA II jumpered for SATA I). Opening you system and swapping out the HD with a raw HD (blank unformatted disk). You should then be able to boot under your DVD and prep the HD with Mac OS-X. Your system should be working booting on the internal HD.

Once you get this far you should then be able to connect your original HD in either a FireWire or USB case/cable harness to your system. Try running Disk Utility on it then install a fresh copy of Mac OS-X on it. Only then try selecting it as the boot disk. Restarting your system it should now come up as the first disk.

by

Add a comment

Hi my friend! I want to say that this article is awesome, nice written and include almost all important info's. Id like to see more posts like this. Check this DVD Replication i hope this also help you.

Was this answer helpful?

Score 0
Add a comment

Add your answer

Cesar will be eternally grateful.
View Statistics:

Past 24 Hours: 8

Past 7 Days: 67

Past 30 Days: 183

All Time: 10,557