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Using Apple Hardware Test
If you suspect a problem with the MacBook Pro hardware, you can use the Apple
Hardware Test application to help determine if there’s a problem with one of the
computer’s components, such as the memory or processor.
To use Apple Hardware Test:
1
Disconnect all external devices from your computer except the power adapter.
If you have an Ethernet cable connected, disconnect it.
2
Restart your computer and hold down the D key as it starts up.
3
When the Apple Hardware Test chooser screen appears, select the language for
your location.
4
Press the Return key or click the right arrow button.
5
When the Apple Hardware Test main screen appears (after about 45 seconds),
follow the onscreen instructions.
6
If 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 might be software related.
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Chapter 4
Problem, Meet Solution