Apple MC812LL/A, MD096LL/A manual Checking for a Hardware Problem, To use Apple Hardware Test

7To reinstall Mac OS X and your applications, follow the instructions in the Mac OS X Installer.

After reinstalling Mac OS X, you can re-download the Apple applications that came with your iMac and other apps you purchased from the Mac App Store. You can restore your other data and applications from a Time Machine or other backup.

Checking for a Hardware Problem

If you suspect a hardware problem, use the Apple Hardware Test application to help determine if there’s a problem with one of the iMac components.

To use Apple Hardware Test:

1Disconnect all external devices from your iMac, except the keyboard and mouse. If you have an Ethernet cable connected, disconnect it.

2Restart your iMac while holding down the D key.

3When the Apple Hardware Test chooser screen appears, select the language you want to use.

4Press the Return key or click the right arrow button.

5When the Apple Hardware Test main screen appears (after about 45 seconds), follow the onscreen instructions.

6If Apple Hardware Test detects a problem, it displays an error code. Make a note of the error code before pursuing support options. If Apple Hardware Test doesn’t detect a hardware failure, the problem may be software-related.

Chapter 4   Problem, Meet Solution 55