I am using a mid 2007, 20" iMac running the most recent software and all my updates are installed. I think I have a video issue and wanted to run apple hardware test, but it won't start up. I have restarted more than a dozen times pressing the "D" key each time, but the test will not start... it just runs through a normal startup leading to the login screen. Any thoughts as to why I can't run it or what I can do to get it going.
Apple just posted an update to the AHT support page 2 days ago, addding the option + D command to start Hardware Test. Thanks Baby Boomer for your help!
ACTUALLY you CAN download it from somewhere and just run it off a USB drive, have a search on github (user upekkha has compiled all the info you need on there) and follow the instructions - make sure you get the right version if AHT for your machine. I ran off a USB drive for a 2008 MBP Unibody no probs (except the extended test took nearly 3 hours!).
Link here: GitHub - upekkha/AppleHardwareTest: Apple Hardware Test Download Links
AHT resides on the original install discs that shipped with the computer, specifically disc #2. If you don't have yours any longer then contact AppleCare and for a small fee they may be able to replace yours. You will need the serial number and a credit card, oh and no you cannot download it from somewhere.
When you upgraded the OS from whatever the computer orginally came with you lost the .diagnostics folder, which enables D key booting to the hardware test.
You can get it here.
http://download.info.apple.com/Apple_Hardware_Test/018-2845-A.dmg (Should be the right one for your Mac).
After downloading the .dmg, you will need to open it using the free demo of Pacifist. Drag the .dmg to the "Open Package" field. It will look like this after you open the disclosure triangles.
Next, you will need to be able to view normally hidden files and folders. .diagnostics is normally hidden.
Paste this command into Terminal.app (in Utilities folder) and hit Enter/Return (to reverse when finished, simply replace "true" with "false."
defaults write com.apple.finder AppleShowAllFiles -bool true ; killall Finder
Next, navigate to /System/Library/CoreServices, and drag the .diagnostics folder that you extracted with Pacifist into that location.That will be in the Macintosh HD folder.
Hide invisible folders and files again.
Post back if you need further instructions. If that's the correct .dmg for the AHT you need, this should enable D key booting again.
Thanks, but it is still not launching. I add the .diagnostics to my core services (and it wasn't there when I opened it) but it still did not boot up the hardware test.
The way the system launched did change. The progress bar under the apple logo paused and went away (just a gray screen, no logo) about 1/3 of the way through, then it came back on at about the halfway mark on the progress bar and finished loading.
Two Three things come to mind: One, that isn't the right dmg from GitHub. The other is I forgot to tell you that you need to change the permissions on .diagnostics. And the third, and maybe most important, is that it may be that D key booting isn't supported on a 2007. Sorry about all that.
So paste this into Terminal and hit return/enter.
sudo chown -R root:wheel /System/Library/CoreServices/.diagnostics
You will be asked for your admin password, which won't appear in any form when you type it in. Disregard the scary message about using sudo.
If you don't have the original discs, you can try opening that dmg from GitHub directly. But I don't think that will work, since it needs a few other steps, including a Disk Utility Restore and a sudo bless, which I've never been able to figure out correctly for those dmgs from GitHub.
See if this works:
How to run AHT w/o the system discs
1) SHUT DOWN the computer (Don't RESTART... shut it down)
2) Hold down the OPTION + D keys
3) Press the Power Button (make sure to hold down the OPTION + D keys first)
4) Continue to hold down the OPTION + D keys until the system enters AHT mode
5) Let the app verify the hardware setup before initiating the test.
6) There are two testing modes. To select the "Extended Test" activate the check box below the Test button.
7) Press Test button to begin test
Above solution provided by an ASC member “wayoverbored”
https://discussions.apple.com/thread/7027974
Just a clarification. Didn't meant that you could run the hardware test directly from the dmg. A dmg isn't bootable. What I meant was that in order to put it on a disc or a flash drive, you need to use Disk Utility Restore and then properly bless it to get to be able to boot. I've never had any luck with those dmgs from GitHub for that. But I am fairly certain that if your computer does D key booting, they can be used for that, in the way I already outlined.
Thanks for all your help.
From what I can tell, my computer should support D key booting. However, I never was able to get it to boot on the hard drive. I did finally find a 2007 mac install bundle (it never said whether it was for iMac or not). I checked the files on it and it had several versions of the .diagnostic AHT files.. including the one you sent me the link for. I set my startup disc to the CD drive, restarted holding the D key and AHT booted. I ran it and it gave me an error code (which I suspected there was something wrong). Now to follow up and see what's going on.
Again, thank you... and everyone who commented, for your help.
What was the error reported?
This is the error code I have: 4M0T/1/40000003:HDD
That means take it in for service! It has a hardware fault, likely a failed HD fan, sensor or the HD is failing.
Most likely the hard drive fan (MOT=motor). Don't run it like that because the drive will overheat and you will kill it.
I too, tried you suggestion. I did the permission change from the recovery sector using Terminal. I could not get pacifist to install it, so I just dragged it over from the dmg. But alas, it will not work.
This totally worked for me. Thank you so much.
Apple Hardware Test will not start up
