Apple Hardware Test: iMac (Mid 2007) and later models

Summary

Learn how to use the Apple Hardware Test (AHT) diagnostic software with the iMac (Mid 2007) and later computers.

Note: The iMac (Mid 2007) and later model computers come with Apple Hardware Test installed on a separate hard drive partition. This partition is not visible in the Finder.

To run Apple Hardware Test from the internal hard drive

  • Restart your computer while pressing and holding the 'D' key on your keyboard during startup.

Note: If Apple Hardware Test was removed by reformatting the drive, or if you cannot open it from your hard drive, you can still use Apple Hardware Test from the 'iMac OS X Install Disc 1' install DVD that came with your computer.

To run Apple Hardware Test from the Install DVD

  1. Insert the 'iMac OS X Install Disc 1' install DVD into the optical drive of your computer.
  2. Restart the computer while pressing and holding the 'D' key on the keyboard during startup.

Note: You can restore Apple Hardware Test to the internal hard drive using the 'iMac OS X Install Disc 1' install DVD that came with your iMac (Mid 2007) or later. To do this, use the Restore feature to reinstall your System Software.

iMac (20-inch, Mid 2007) iMac7,1 3A125
iMac (24-inch, Mid 2007) iMac7,1 3A126 or 3A127
iMac (20-inch, Early 2008) iMac8,1 3A138
iMac (24-inch, Early 2008) iMac8,1 3A139
iMac (20-inch, Early 2009) iMac9,1 3A156
iMac (24-inch, Early 2009) iMac9,1 3A157
iMac (21.5-inch, Late 2009) iMac10,1 3A176
iMac (27-inch, Late 2009) iMac10,1 3A179
iMac (21.5-inch, Mid 2010) iMac11,2 3A195
iMac (27-inch, Mid 2010) iMac11,3 3A202
iMac (21.5-inch, Mid 2011) iMac12,1 3A212
iMac (27-inch, Mid 2011) iMac12,2 3A213

Note: You can locate the Model Identifier on your computer using Apple System Profiler:

  1. Go to the Apple menu and choose About This Mac.
  2. Click More Info...
  3. Under Hardware Overview, see Model Identifier.

 

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