If you have a Mac, which was shipped with OS X Lion, you might have wondered that pressing the “D” key right after the pressing the power button will not load Apple Hardware Test (AHT), in case if you wish to identify any issues in hardware of your Mac. Click on the link given below:
Here, it is stated : “Some Macintosh computers that shipped with OS X Lion and later support the use of Apple Hardware Test over the Internet”, but notice that the correct key or key combination that is needed to be pressed in order to initialise AHT is not given.
Let me explain how to perform the AHT over the internet.
- Power the laptop on. Make sure that there is an active internet connection
- Before the grey screen is appeared, press D and ⌥ (alt). Then the screen given below should appear. Don’t be alarmed by the terms “Internet Recovery” as that is the nomenclature given to the internet-based AHT.
Finally, follow the on-screen instructions. These will be the same as the ones given from Step 3 onwards, which are provided in the link above.
Hope this helps.