Now if you’re having problems with your Mac
and you think it’s the hardware and you’re at the point where you’re just about either
to call Apple or go to the Genius Bar, one of the things you may want to do is run Diagnostics
Mode. This could tell you some things about what
might be wrong with your Mac hardware. Now go to this page here and this will tell
you how to do it. But I can walk you through the steps. It’s pretty simple. But do note that it’s different depending
upon the age of your Mac. If it is a Mac from before June 2013 then
you’ve got a different set of instructions here. Very similar but slightly different. Basically what you’re going to do is restart
your Mac and hold the D key down. Let me show you. So to access diagnostic mode I’m going to
restart the Mac andI’m going to hold the D key down. Going to confirm here. Then the D key should tell it to restart in
this special diagnostics mode. Now this won’t work if you’ve had your firmware
password set. If you don’t know what that is then you probably
haven’t set it. But if you have then you need to remove your
firmware password. Now you can see this is the beginning of Diagnostics
Mode. I first need to choose a language. Then it starts. It takes about three minutes on this Mac but
on other Macs it may take longer. So here you can see it says there are no issues
found. Now if it had found issues it would provide
you with these reference codes here which you could do searches for online or simply
report to Apple when you call in to them for help or when you go and visit the Genius Bar. At this point here I’m done and I can simply
restart or shut down my Mac. Now back at this web page from Apple you can
see here an example of something that may come up. For instance, in this example an issue with
the power adapter, some WiFi issues and it gives you some reference codes here. Then it gives you the ability to run the test
again. Obviously I didn’t see that because no issues
were found. You can look at the rest of this page here
and see there’s some shortcuts that you can use. Like, for instance, run test again, Command
R. Or restart is R and S. So take a look through this to see what you might be able to get
from running this hardware test. But in general if somebody tells you to run
the hardware test or the Diagnostics Test on your Mac this is what they mean and this
is how to do it.