I'm using a 13" mid-2012 Macbook Air (yes, it's an old machine:)). It's running MacOS Catalina, 10.15.6. It works fine (if sluggishly, no surprise there!), but I'm getting sudden battery shutdowns, and I'd like to use the hardware self-test to see how many cycles the battery has been through. It appears to me that I should be able to start the "Apple Hardware Test" on this machine by holding down 'd' during startup, but instead, holding down 'd' takes me to "Internet Recovery", which isn't what I want at all.

Any idea what's going on, and how to access Apple Hardware Test on this machine?

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    RE: "I'd like to use the hardware self-test to see how many cycles the battery has been through" -- You can get battery info from > About This Mac > System Report… > Hardware > Power as it shows Cycle Count:. Or, from Terminal: system_profiler SPPowerDataType Sep 19, 2020 at 14:20

1 Answer 1


Just because you hold d doesn’t mean the signal is correct. Also, I wouldn’t put any effort into running home diagnostics. That only tests for things like “One of the four tires on your car is missing.”

My move for this symptom is to call Apple or chat with them online. Ask for them to send you a link to test your battery remotely while the OS is running. That will tell you far more. Also, if you can’t get the os running or erase, reinstall it from recovery, then you have larger issues than even getting diagnostics to run.

They will either fix your issue or offer a flat rate repair so you know how much worst case a repair will be.

In the end, you’re in the correct screen you need to decide how to move forward despite your wanting a quick diagnostic. You need to get to system information and have the battery specific diagnostics run by Apple at this point.

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    I’ve even have it miss that half the RAM was gone / failed on a Mac. It’s rubbish - pressing d should show the number to AppleCare and explain how to do a backup / erase install IMO.
    – bmike
    Sep 19, 2020 at 14:33
  • hmm... can you explain what you mean by "the signal is correct"? Sep 19, 2020 at 19:44
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    Failing hardware / battery can send the wrong key code. That’s an electrical signal. However. If it boots, you can know if the keyboard works, but I’ve seen odd things when the firmware is interpreting the USB signals vs when the OS interprets them. @JohnClements hopefully, you can boot to an OS and check the power settings in system information or get Apple diagnostics - that really tells you how the battery health is.
    – bmike
    Sep 19, 2020 at 19:54

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