Did I remove Apple Hardware Test with SSD upgrade?

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Did I remove Apple Hardware Test with SSD upgrade?

So I've been enjoying the use of a new SSD, but I've been seeing a few things that seem a little bit different including a bluish screen at startup. Someone here suggested running Apple Hardware Test, and I did, but it seems different now. I cloned my 7200 RPM WD 750 drive using CCC to a SanDisk Ultra 3D 512 using Carbon Copy Cloner 5.0.5. I might have done a few things after I saw unusual activity. One was when I tried to do an external boot of my freshly cloned drive holding option. After a much longer than average delay I forced a power down and just installed the SSD anyways, which seemed to boot fine. I've since completely reformatted that source drive and the backup drive that I used before and cloned from my SSD. If AHT was on those volumes it's gone now.

It seems to pull it up AHT from the internet now, with the Internet Recovery globe. I thought that AHT was built into the firmware, but I guess it's actually in a hidden partition on the drive?

Is there any way to rebuild AHT on my new drive? I know at this point I can use it over the Internet, but I'd like to be able to run it when I don't have internet access or issues with internet access are what I trying to diagnose.

MacBook Pro, macOS High Sierra (10.13.2), (13" mid-2012)

Posted on Jan 26, 2018 11:14 AM

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Answer 1

y_p_w Author

Level 6

17,642 points

Jan 26, 2018 11:33 AM in response to JimmyCMPIT

JimmyCMPIT wrote:

if your 2012 shipped with 10.7 see this link

How to use Apple Hardware Test on your Mac - Apple Support

I know that stuff. Mine shipped with Mavericks though. I'm just trying to see if there's any way to restore it just in case I don't have internet access or Apple might discontinue support. I doubt the latter, but I'd like to be self-sufficient.

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Answer 2

Jan 26, 2018 12:04 PM in response to y_p_w

Apple Hardware Test:

The diagnostic was installed on the Boot drive at the factory, in the directory:

/System/Library/CoreServices/.diagnostics (an invisible directory)

... Unfortunately, there is no software responsible for putting it back there after you erase or replace the boot drive.

A User has assembled all the diagnostics they could find, and placed them on an Open Source web site here:

GitHub - upekkha/AppleHardwareTest: Apple Hardware Test Download Links

You can download the one for your Mac, place it on a USB-stick, and bless the USB stick to make it bootable using instructions on that site. You can also put the invisible .diagnostics folder back where it should be on your boot drive, but you must be booted from another drive when doing so, because System Integrity Protection locks up the folder where it needs to go, and it is an invisible folder, so Finder has trouble moving it in the usual way.

If you go to build a bootable USB-stick, you will notice that the structure of the .diagnostics folder inside the CoreServices folder is maintained, even on the stand-alone diagnostics.

--------

Only Macs that shipped much later use the Apple downloadable diagnostic, accessible from Internet Recovery. (Although if your Mac is not working properly, i question its ability to accurately download the diagnostic.)

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Answer 3

y_p_w Author

Level 6

17,642 points

Jan 26, 2018 12:30 PM in response to Grant Bennet-Alder

Thanks. I'll have a look at that.

I can't even seem to bring up recovery HD from my new SSD, although I cloned it back to my 7200 RPM drive and that seems to have a new volume called Recovery 10.13.3. I'm at home today so I tried reinstalling the old hard drive. When I tried running AHT from it, it said it couldn't find it and it would try to run it from Recovery HD.

I had my original HD die on me a few weeks ago, but I had a working clone. I would have thought that it would have all copied over with each clone.

I'm trying to copy it over now from the mounted image. I didn't see anything with the hidden directory, but I looked up that I need command-shift-. to make hidden files visible. I'm not quite sure how to access a mounted image in Terminal. I copied over .diagnostics and I'm going to give it a try now. I just hope it doesn't destroy everything.

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Answer 4

y_p_w Author

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17,642 points

Jan 26, 2018 1:00 PM in response to Grant Bennet-Alder

Just a follow-up. I tried copying it over with my HD installed back in to take care of the SIP issue. I'm pretty sure I got the right file. It still goes straight to Internet Recovery to look for it. When I installed my 7200 RPM hard drive it wouldn't run AHT at all holding D - just that message about looking for it from Internet Recovery, and options at the bottom to restart or shut down.

This may simply all stem from my original boot drive being corrupted, so I'm guessing it's not worth it if I can still access AHT via Internet Recovery.

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Answer 5

Jan 26, 2018 6:04 PM in response to y_p_w

You will see in the article on the GitHub site (that holds all the Apple hardware test binaries), that there is a command called bless, that is used to make the USB-stick bootable. What that does is to have the Mac write the location of the first boot file in a "magic place" on the drive, because the File System is not available early in the boot-up process.

Once the .diagnostics folder location has been blessed, that folder will be bootable with the D-for-diagnostics key. Without blessing, it cannot be found. At the point when you want the .diagnostics folder, there is no File System, so you can't search for it.

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Answer 6

y_p_w Author

Level 6

17,642 points

Jan 26, 2018 7:18 PM in response to Grant Bennet-Alder

Grant Bennet-Alder wrote:

You know, I thought it should, too. But I tried it without blessing, and I could not get it to work.

That worked, but I guess only for the drive. I don't seem to be getting back the D startup to get to AHT. It still goes straight to the Internet Recovery version of AHT. I can live with it since I have it now in a form where I don't need internet access. It's only 51 MB, so I set up a tiny partition.

Some different things though. The version linked for MacBook 9,2 was 3A237, while the one pulled up from Internet Recovery was 3A244. The version linked (3A237) properly identifies my machine as a Core i5 processor, while 3A244 identifies it as a Core i7. I remember whenever I ran AHT before I'd see that odd identification.

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