Apple Hardware Test at Startup

I restarted my computer and it is not seeing the startup disc. Ran disk utility through C drive boot disk, but now when I reboot I get a screen with the Apple Hardware test icon, a right arrow icon, what looks like the refresh screen icon and the CD disc icon (with an X). The b/w clock cycles for a bit then nothing. Disk utility did its verify and repair tasks and indicated repairs were made.
Suggestions on a next step to get the computer to boot up?

Similar Messages

Apple Hardware Test (AHT) invoked at startup with 'ALT-D' not 'D'

Although several reasonnaably reliable sources (including such page as http://support.apple.com/kb/HT1533 ) mention that pressing 'D' at startup will invoke the Apple Hardware Test startup option, at leats on my Macbook Pro 2011 with OSX Lion, EFI 2.8 it is really 'ALT-D' that invokes AHT not 'D'. Pressing the 'D' at startup simply seems to hangs bootup until I release the key.

OS X Lion- About OS X Recovery
OS X (Lion/Mountain Lion)- About OS X Recovery
Computers that can be upgraded to use Lion Internet Recovery
The above documents what keyboard shortcuts are used to invoke AHT and some added functions in Lion and/or Mountain Lion.

Can't boot off Apple Hardware Test disk

Can anyone suggest why my laptop won't boot off of its Apple Hardware Test disk anymore? I have not tried it in years, but want to try now. I have the original, and a copy I made years ago, and neither will boot. I can select them at startup disks in that preference pane in OSX, but then it fails to find it, and boots into OSX. I can boot into OS9 on the hard drive. I was able to partially boot off of a different AHT disk from my 12" Albook G4, but it gave the message that I can't use that disk since it is not meant for the Tibook. One idea is that TechTool tells me that "macintosh startup file was absent", and the Help file states:
"The Startup file is intended for use by systems that do not have built-in ROM support for booting from HFS Extended volumes. The first eight extents of the Startup File are stored in the Volume Header. This makes them easy to locate and read into memory. This file contains information used by the computer’s ROM to determine what program will boot the computer. In almost every case, this will be configured to point to the preferred System."
But it does not tell me how to restore this Startup file.
-how can i get my startup file back?
-my computer boots fine off the hard drive, so is this file used only to boot off a CD?
-any ideas why i can't boot off my AHT CD?

Hi, t. (That alias of yours sure is a mouthful.) I think in your shoes I would pose the question to the tech support people at Micromat (TechTool's developer). It's their error message, after all, and they should be able to explain it to you in as much detail as you need. Perhaps they'll shed some light on the original problem in the process.

Cannot start-up to the Apple Hardware Test — MacBook Pro & Lion

Whenever I try holding the D key before and throughout all of the start-up process, it simply makes the grey screen appear for longer, and slow the whole process... but never beings the Apple Hardware Test.
I'm following Apple's official instructions:
To start up your computer in Apple Hardware Test:
Press the power button to turn on your computer.
Press and hold the D key before the gray startup screen appears. An Internet-enabled connection via Ethernet or Wi-Fi is required to use this feature.
Note: Some Macintosh computers that shipped with OS X Lion support the use of Apple Hardware Test over the Internet. These computers will start up to an Internet-based version of AHT if the hard drive does not contain AHT.
Why doesn't it work?
My MBP was shipped as follows:
For Apple computers that shipped with Mac OS X v10.5.5 to 10.6.7, Apple Hardware Test is located on the Applications Install Disc 2 and should be included with your computer.
But I have upgraded to Lion! Do I need the disk still? If so, why am I to lumber around a disk from a previous OS... good that I didn't throw it out!

I'm trying to find the answer to a similiar question. Here's my thread.
https://discussions.apple.com/thread/3549995

G4 that will not boot from any disc EXCEPT the Apple Hardware Test CD

We have a DP 1ghz Quicksilver PowerMac G4 that will not boot from any disc EXCEPT the Apple Hardware Test CD that came with the machine.
We were in the process of installing 10.4 Tiger before placing it for sale.
The Mac was originally OSX Server 10.1 that we later converted to a worksation running 10.3 Panther.
It has 1 GB of memory, 80GB hardrive, 250MB Zip Drive and a Radeon 7500 video card.
Since this machine only has a CD-R drive and not a DVD-R, we installed Tiger using another Mac via Target Disk Mode. The installation process went well, but when I tried to reboot I got a Kernel Panic right after startup screen with the grey Apple logo.
On some reboots we get to the blue startup screen, others it stops at the grey Apple logo, others a black box like the a Kernel Panic - but with no text. Twice it went directly into Open Firmware.
We have done the following during our troubleshooting:
- Reseat RAM, Video Card, Hard Drive, Zip & CD-R connections
- Remove RAM 1 stick at a time and reboot
- Replace RAM with RAM from another working Quicksilver
- Replace Video Card with one from another working Quicksilver
- Zap PRAM
- Reset CUDA switch
- Unplug the MAC and remove everything (RAM, Battery, etc) for 30 minutes and try to reboot
- Tried booting from the Macintosh Server G4 Software Restore CD
- Tried booting from Mac OS X Server CD
- Tried booting from AppleCare Protection Plan CD with TechTool
- Tried booting from Diskwarrior CD
- Tried booting from an external FireWire drive with a disk image of Tiger OS Install
- Tried booting with the hard drive disconnected
The Mac WILL boot from the Apple Hardware Test CD and will pass ALL of the extended tests.

Conventional wisdom says that any Mac that will not boot up from a System/Install CD OS 9 or an Install CD Mac OS X, has a Hardware problem.
The diagnostic CD is a red herring because it uses a very primitive method of reading the CD, and so does not properly represent the machines general ability to read CDs.
I would look at the CD drive cables, etc, and see if another drive gives different results.
You have not mentioned using the Startup Manager (option key at Startup) to do any checking:
HT1310- Startup Manager: How to select a startup volume

Won't Boot to Apple Hardware Test or accept Boot Commands

Hi All,
I would appreciate some help with this issue, I am trying to boot up to the Apple Hardware Test on my Install Disk 1 that shipped with my MacBook Pro 2.4GHz Model #A1226 ordered new with 4 gigs of memory (around Aug. 2007). I am currently running 10.5.6 and the install disk of course contains the Tiger OS. I have nothing plugging into my computer, other than the Power Adapter. I have the proper install disk inserted in the computer and am holding down the "d" key on my built in keyboard throughout startup, but it will not go to the AHT. It simply boots to the normal login screen for Leopard. In fact the only boot commands that I see any visible or audible confirmation that it has taken effect is the option key, taking me to selecting a Startup Manager and holding down the Power Button gives me a tone from the internal speaker after a few seconds.
Below are what I have tried with seemingly no effect:
"d"
"c"
"t"
Option-Command-"p"-"r" (no beeps)
Command-"v"
Command-"s"
Shift (not sure I should see or hear any confirmation, I don't have any login items set right now so I can't tell if it has any effect)
I have not tried an of the networked drive boot commands as I don't have any networked drives
The only way I have been able to boot from either the optical drive or another disk is either holding down the option key during boot up or selecting the drive from the startup manager in system preferences.
I can't seem to access the AHT an in any way. The reason I am trying to access it is because I have had a few weird intermittent problems that I can't put my finger on and would like to be able to rule hardware out.
I also just replaced my HD with a WD 320 gig drive after my original drive failed due to a physical error. I just restored my data, and all seems to be running well after a permissions repair and a disk repair while booted up on my install disk.
The intermittent problems I was talking about are very vague and rare so I is difficult to describe them other that just a hunch that something is still a bit off. One is the display, every once in a while, showing what looks like a massive bar code or UPC code on my screen. This is not like the bands with soft edges that seem to be a well documented issue with the early MBP but transparent lines of alternating width and brightness with hard edges. Again it looks just like a UPC code transposed on my screen. The other items are random freezing of the OS or the mouse and the fact that my keyboard does not respond to any but a few boot commands. Again all the things are either rare and intermittent or do not come up in daily use of my machine. But when taken together, seem to add up to the conclusion there is still some issue present (at least in my mind).
To recap my specific questions relate to not being able to run the Apple Hardware Test and many of the boot commands having no effect. If you can shed light on the other items mentioned, great!
Thank you!

At a guess, I would think this error code has to do with the video artifacts you are experiencing. You might try reseating all the cables to the display. If the position of the screen makes a difference, there may be damage to a cable, particularly where it goes through the hinge.
Apple is the keeper of the error codes. If you have access to an Apple Store, you could probably ask about this.
Don't know about the other intermittent problems. Does an external keyboard work? If so, there's likely a problem with the internal, maybe even again, a cable or connection.
You could also try creating a new use account and see if the keyboard and mouse problems persist. If not, there could be some sort of software corruption in your usual account. Ditto with the freezing.
Good luck!

Won't boot from Apple Hardware Test or 10.1 Install disc

Disk utility states that I need to boot from a CD and then run Disk Utility to repair my disk. However, neither CD seems to be recognized as a viable startup disk from either holding down the C key or trying to select it as a startup disk in System Prefs.
FYI, I am running 10.6 and trying to boot from a 10.1 disc and an Apple HT disc with SW version 1.2

There is no way any Intel Mac will run with 10.1 -- it was released before there was any Intel support in the OS.
Every Mac model requires a specific version of the Apple Hardware Test to support its hardware. (If yours is the "Late 2008" black MacBook, the Mactracker database says it requires version 3A147.) Somewhere in the fine print of your original grey system disc set, or on any other grey system disc for any model, you will find the version of AHT it contains, if it contains any version. Unless that version is the same as your Mac requires, it won't work.

How do I run Apple Hardware Test on a 2012 MacBook Air with 10.8.4?

Hello everyone,
I am trying to run Apple Hardware Test on a mid-2012 MacBook Air with 10.8.4 installed. Whenever I restart and hold the letter D my computer goes into internet recovery mode and asks me to connect to Wifi... Please help, thanks!

Using Apple Hardware Test on computers with OS X 10.7 or later
Mac NoteBook and Desktop computers shipping with OS X 10.7 or later have a partition on the hard drive or flash storage that contains AHT. To start AHT on these computers please follow these instructions:
Press the power button to turn on your computer.
Press and hold the D key before the gray startup screen appears.
It takes a minute or so for AHT to start up and inspect your hardware configuration. While this is taking place, an icon appears on the screen:
When the process is complete, select your language and click the right arrow. If you aren't using a mouse, you can use the up and down arrows to select a language and then press the Return key.
The AHT console appears. You can choose which sort of test or tests to perform:
To perform all of the basic tests, click the Test button or press the "T" key or the Return key.
To perform a more thorough diagnostic test, select the "Perform extended testing" checkbox under the Test button before you click the Test button.
Note: Your test results will appear in the window in the bottom-right of the console.To exit AHT, click Restart or Shut Down at the bottom of the window.
Some Macintosh computers that shipped with OS X Lion and later support the use of Apple Hardware Test over the Internet. These computers will start up to an Internet-based version of AHT if the hard drive does not contain AHT. An Internet-enabled connection via Ethernet or Wi-Fi is required to use this feature. Internet-based AHT functions the same as AHT on the hard drive or flash storage outlined above.
The Mac NoteBook and Desktop computers listed in Computers that can be upgraded to use OS X Internet Recovery will require a firmware in order to support the Internet version of AHT. Without this update you may see the behavior discussed in this article.
http://support.apple.com/kb/HT1509

Apple Hardware Test problems

Hi All. I have a very weird problem here, as I can't get the Apple Hardware Test to start on my late 2008, 2.66 MBP15 inch model# MC026LL/A (released early 2009 as a quiet upgrade from 2.53). Here's the story:
I opened up my machine as usual one morning, and the optical drive made a very weird noise I never heard before. So I decided to run the Apple Hardware Test (AHT) to see if anything was amiss. Well, I inserted the second install disk, held down the "d" key, and restarted the machine. It began to boot into the hardware test, but just after the AHT screen appears the computer just shut down. This happens every time I try to run the AHT.
I went to an Apple Store while I was on holiday in Brisbane (they don't have one here in Adelaide), and the genius said it was likely a bad optical drive. Well, I returned to Adelaide last week and had the local Apple Authorized store replace the optical drive. Tried to run AHT once again, and the same problem persists. So the original problem wasn't with the optical drive.
I thought maybe I accidentally used the startup disks for my wife's late 2008 15inch, 2.4, MBP (the one actually released in late 2008). I've looked around for the other sets of disks and can't find them. So here's what I'm asking help for: can someone who owns a 15inch MBP 2.66 15-inch (released in early 2009, model# MC026LL/A ) please tell me what the part # is for their set of install disks? It is written on the plastic sleeves of the install disks. And, could this person please tell which version of AHT is written on the disk itself? The set I have (which I think might be my wife's) has AHT version 3A158.
Might this be the problem, or should my computer still be able to run the hardware test using my wife's disks? I know they are both technically late-2008 15inch unibody MBPs, but I think my 2.66 (again, quietly updated and released in early 2009) might require a different AHT version, which would explain my inability to run the test. If not, what might be causing my computer to not run the AHT? I tried reinstalling OS X to no avail.
Thanks for all of your help!

I think I share your skepticism--if your Mac was shipped with the later version of the OS, you should not have been able to do a clean install with discs of an earlier version. It looks like some machines originally shipped with OS X v. 10.5.5 and others with OS X v. 10.5.6. I don't remember just when 10.5.6 came out.
Your two machines are likely very similar in build, and maybe similar enough for the OS to install. It may be that the AHT is specifically designed for the hardware in each machine, and that would be a bit different.
As someone else said in another thread, there ought to be a tutorial on how to keep track of the original install discs since they are always getting lost. Maybe a secure note in the keychain or something like that.
Out of curiosity, does the AHT work on your wife's machine? If not, there could be a problem with the install disc itself, and if so, you might be able to get a free replacement under warranty.
Good luck!

Apple Hardware Test on a late 2008 MBP new HDD

Hey Community!
I own a Mac Book Pro - Late 2008 shipped with OSX 10.5.5. Currently I a new 500GB HDD and a 265 SDD are running in my MBP. The Super Drive is in an external USB Housing. Current OS X is version 10.7.1.
I need to run the Apple Hardware Test, because sometimes the system seems to freeze for at least 30 seconds.
What I've already tried:
*) Holding down "D" at the startup -> nothing happens, normal startup
*) setting start volume to external fire wire optical drive, insert 10.5.5. Installation disc, restart, holding down "D" -> startup with installation wizard
*) same with 10.6 Installation disc
*) same with choosing the Backup Partition when holding down "Alt" at startup and then pressing "D"
Always, I was connected via WIFI and Ethernet.
Can someone give me an advise how to run the Apple Hardware Test, or how to reinstall it on the new SDD Harddrive, where my system is mounted?
Thank u and greetings from Austria
Claudio

Try using your disk utility to read the drives. I'm not at my computer now but if you go into utilities->disk utility you might be able to solve it from there.
Also try holding down the C key on boot or esc.

Files/Folders Sticking to Mouse Pointer - Not Releasing (Reset PRAM & Apple Hardware Test Fail to Run)

I've been having two issues with my Late 2008 MacBook Pro 15-inch - Running OS X 10.8.5 (Mountain Lion). Unable to Reset the PRAM and Run Apple Hardware Test (AHT).
On a random basis - File/Folder icons are Sticking to the Mouse Pointer - Not Releasing. I've done everything from trashing finder preferences, making sure Universal Access preferences are off, Restoring Defaults in the Energy Saver System Preferences, Resetting the System SMC. Another post mentioned that this is being caused by the Graphics Driver not working correctly - and mentioned to put the MBP to sleep, then wake it up, and the files/folders are no longer sticking to the mouse pointer. This works for me and released the sticking items in the Finder.
OK, Good this is a simple fix, BUT, what is really causing this issue, and how may it be fixed or repaired?
I also tried to Reset the PRAM and Run the Apple Hardware test (AHT), and these both fail to run on my MacBook Pro with OS X 10.8.5.
1) Resetting the PRAM:
Shut down the MBP, press the power button, and hold down at the same time <option><command>-P-R. The Reset PRAM process never starts up, but rather I receive the Padlock/Password Login which logs me into the Restore System Utilities. I'm unable to Reset the PRAM.
2) Apple Hardware Test (AHT):
Shut down the MBP, press the power button, and hold down the "D" key, the system boots up as normal and does not enter the AHT.
The File/Folder Finder sticking to the mouse pointer issue is very annoying. Does anyone have a solution to resolve this issue?
- Cheers

HI Barbara,
It sounds like the hard drive is failing or has failed. Boot from your Mac install disc and if you can run Disk Utility in case the startup disk needs repairs.
Insert your install disk and Restart, holding down the "C" key until grey Apple appears.
Go to Installer menu and launch Disk Utility.
Select your HDD (manufacturer ID) in the left panel.
Select First Aid in the Main panel.
*(Check S.M.A.R.T Status of HDD at the bottom of right panel. It should say: Verified)*
Click Repair Disk on the bottom right.
If DU reports disk does not need repairs quit DU and restart.
If DU reports errors Repair again and again until DU reports disk is repaired.
When you are finished with DU, from the Menu Bar, select Utilities/Startup Manager.
Select your start up disk and click Restart
While you have the Disk Utility window open, look at the bottom of the window. Where you see Capacity and Available. *Make sure there is always 10% to 15% free disk space*
If you cannot boot from your install disc, try booting in Safe Mode
What is Safe Mode
Carolyn

Using Apple Hardware Test?

Hi, I need some assistance.
I've got a MacBook Pro from 2011. That have some hardware, I'm sure. Please see this post. https://discussions.apple.com/thread/6029708
So I'm trying to use Apple Hardware Test. http://support.apple.com/kb/HT1509?viewlocale=en_US
But I can't make it work. And I've read the instruction for using the Apple Diagnostics test as well. http://support.apple.com/kb/HT5781?viewlocale=en_US
And it seems to me to be exact same approach.
Using Apple Hardware Test on computers with OS X 10.7 or later
1. Press the power button to turn on your computer.
2. Press and hold the D key before the gray startup screen appears.
3. It takes a minute or so for AHT to start up and inspect your hardware configuration. While this is taking place, an icon appears on the screen...
To start Apple Diagnostics:
Turn off your computer if it is on by choosing Shut Down from the Apple () menu.
Press the power button to turn on your computer.
Immediately press and hold the D key until Apple Diagnostics begins.
If you previously selected a language for” the computer, a "Checking your Mac" screen will appear in that language.
Can anyone instruct help me? I've tried using 25 times enabling the AHT. But the little icon never shows. I just get the regular login screen after some time.
MacBook Pro early 2011.
OS X 10.9.2

Sweet, OGELTHORPE
That worked! Apple own instructions are really not impressive. Haha. ****.

Can't get Apple Hardware Test to work

So I'm trying to run the Apple Hardware Test. I start the computer up and hold "D". It boots into OS X like a normal startup. So, I plug in the Ethernet and hold option-D to do the AHT from the Internet. It tells me "Apple Hardware Test does not support this machine".
So, I try to install the "iMac EFI Update 1.8" from http://support.apple.com/kb/DL1493 (which is for my iMac model, which is a iMac (Mid 2010)), but it says "This software is not supported on your system." I also tried the later version, v1.9, from http://support.apple.com/kb/DL1498 but it isn't for my iMac and so I get the same error.
So now I'm stuck. What should I do now?

Thanks that was it. It says AHT on the disk itself. I successfully ran it, and it found no problems ("No trouble found.") I ran the basic test only because I have 16 GB RAM, and so I imagine it would take a long time to run the extended—probably at least two hours? And I don't know what more that would find that the basic wouldn't?

Error 4PRC in Apple Hardware Test

Hello,
I have a 24" iMac (2.16GHz Core Duo, 1.5GB RAM) from late 2006. A few days ago, the display went black although the power stayed on. I turned it off, and it hasn't been able to boot since then. Whether I try to boot normally, in safe mode, or from the install DVD, the same thing happens: (1) happy startup sound with gray Apple logo; (2) that screen darkens and *sort of* a kernel panic message appears in the center. I say "sort of" because the kernel panic message's rectangle is in the right place and some of its text is readable, but partway down the rectangle it looks as though the drawing is offset somehow. Anyway, that's how this problem manifests itself: a kernel panic very early in the boot process.
Miraculously, the Apple Hardware Test starts up successfully from the install DVD. Both the normal test and the extended test give the same result: the RAM passes its tests, but when it reaches the CPU, the following error message appears, and the tests stop:
4PRC/1/40000003: Processor
That looks bad. I searched the web and various forums (including this one) and found very little information. An Apple document marked "Error Codes, Apple Hardware Test version 3A117" suggests that the appropriate action is to replace the processor.
I suspect that if I take the iMac to my local Mac repair specialists, they will offer to expensively replace the motherboard. I'm an old UNIX nerd and have tinkered with lots of machines other than Macs; can I simply replace my iMac's CPU myself?
Or is CPU replacement in fact unnecessary, when some other fix might work? Does anyone have specific advice about this error message?

In case it's helpful, here's a textual description of the panic from single user mode startup (which fails just as badly):
hi mem tramps at 0xffe00000
PAE enabled
64 bit mode enabled
standard timeslicing quantum is 10000 us
vmpagebootstrap: 382549 free pages
migtable_maxdispl = 71
Enabling XMM register save/restore and SSE/SSE2 opcodes
84 prelinked modules
ACPI CA 20060421
AppleIntelCPUPowerManagement: ready
AppleACPICPU: ProcessorApicId=0 LocalApicId=0 Enabled
AppleACPICPU: ProcessorApicId=1 LocalApicId=1 Enabled
Copyright (c) 1982, 1986, 1989, 1991, 1993
The Regents of the University of California. All rights reserved.
using 7864 buffer headers and 4096 cluster IO buffer headers
Enabling XMM register save/restore and SSE/SSE2 opcodes
Started CPU 01
panic(cpu 1 caller 0x001A49CB): Unresolved kernel trap (CPU 1, Type 14=page fault), registers:
CR0: 0x8001003b, C5å: 0x19d0010c, CR3: 0x0120f000, CR4: 0x000006e0
EAX: 0x037a9198, EBX: 0x037de760, ECX: 0x0041fa40, EDX: 0x037ffc80
CR2: 0x19d0010c, EBP: 0x1cfb3e58, ESI: 0x0378bdc0, EDI: 0x037602c0
EFL: 0x00010212, EIP: 0x19d0010c, CS: 0x00000008, DS: 0x00000010
Debugger called: <panic>
Backtrace, Format - Frame : Return Address (4 potential args on stack)
0x1cfb3c38 : 0x128d0d (0x3cc65c 0x1cfb3c5c 0x131f95 0x0)
0x1cfb3c78 : 0x1a49cb (0x3d2a94 0x1 0xe 0x3d22b8)
0x1cfb3d88 : 0x19b3a4 (0x1cfb3da0 0x4b00d0 0x1cfb3dc8 0x4)
0x1cfb3e58 : 0x3c10b5 (0x37de760 0x378bdc0 0x1cfb3e88 0x389d2b)
0x1cfb3e88 : 0x38af5f (0x37de760 0x378bdc0 0x1cfb3eb8 0x38998b)
0x1cfb3eb8 : 0x38ed6e (0x3821f00 0x37602c0 0x37de764 0x3821f08)
0x1cfb3f38 : 0x38ebb5 (0x3821f00 0x37ffe40 0x0 0xffffffff)
0x1cfb3f88 : 0x3902fa (0x3821f00 0x0 0x134db9 0x390228)
0x1cfb3fc8 : 0x19b21c (0x380dd50 0x0 0x19e0b5 0x375c3b4) Backtrace terminated-invalid frame pointer 0x0
Kernel version:
Darwin Kernel Version 8.11.1: Wed Oct 10 18:23:28 PDT 2007; root:xnu-792.25.20~1/RELEASE_I386

Imac 24 aluminum - apple hardware test using wireless keyboard

The manual that came with my imac describes the steps to run the apple hardware test as follows:
1. disconnect all external devices, except keyboard and mouse
2. restart mac holding the 'd' key
The apple hardware chooser should appear next.
When I do these steps it goes right to my desktop every time. I am running a mac wireless keyboard and mac mighty mouse.
Anyone have an idea how I can get the Apple Hardware Test up?
Thanks.
Message was edited by: pathfinder31

Hi,
It can take a few minutes for the AHT to appear after booting, D key, etc:
http://support.apple.com/kb/HT1509
Try shutting down your iMac, reboot and THEN do the AHT.
Are you able to boot from the restore disk?
To check the hard disk:
Open Disk Utility, in the Utilities folder in the Applications folder.
Insert your Mac OS X Install disc in your computer’s optical drive or an optical drive connected to your computer, and then restart your computer. When you hear the startup tone, hold down the C key until you see the progress indicator, which looks like a spinning gear.
Follow the onscreen instructions until the Menu Bar appears with the Utilities menu in it, choose Utilities > Disk Utility, click First Aid, and then click the Verify button. If DU reports errors, click Repair. When it's finished, from the Menu Bar, select Utilities/Startup Disk. In the Startup Disk window select MacintoshHD 10.x.x and click Restart.
Carolyn

Apple Hardware Test at Startup

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