This is a weird one. A few days ago my iMac started shutting down and/or restarting itself. I couldn't get it to stay on for more than a few seconds. Thing is, even after shutting it down, it would start itself up on its own volition after a few seconds or minutes.
I booted to an external, swapped RAM, reset SMC and PRAM, booted in diagnostic mode, disconnected all peripherals -- all the standard troubleshoot, but to no avail. Also, confirmed that "Start up automatically after a power failure" is not on in Energy Saver.
Next day to Genius Bar, it boots right up, passes their diagnostics, so we talk about options and I end up taking it home to see what happens. It was fine all last night and I really put it through its paces. Shut it down. This morning I find it ON, showing a screen that says Reset password. This screen normally comes up if you get to the login screen (FileVault on) and then hold down the power button to shut it down.
Doesn't seem to be a software issue, since it happened when trying to boot to a known quantity external, Recovery mode, Diagnostic mode, etc. My best guesses are the power supply and/or the power button itself -- does this make any sense? Any ideas would be greatly appreciated.
4.2 GHz Quad-Core Intel Core i7, MacOS 13.1
I booted to an external, swapped RAM, reset SMC and PRAM, booted in diagnostic mode, disconnected all peripherals -- all the standard troubleshoot, but to no avail. Also, confirmed that "Start up automatically after a power failure" is not on in Energy Saver.
Next day to Genius Bar, it boots right up, passes their diagnostics, so we talk about options and I end up taking it home to see what happens. It was fine all last night and I really put it through its paces. Shut it down. This morning I find it ON, showing a screen that says Reset password. This screen normally comes up if you get to the login screen (FileVault on) and then hold down the power button to shut it down.
Doesn't seem to be a software issue, since it happened when trying to boot to a known quantity external, Recovery mode, Diagnostic mode, etc. My best guesses are the power supply and/or the power button itself -- does this make any sense? Any ideas would be greatly appreciated.
4.2 GHz Quad-Core Intel Core i7, MacOS 13.1
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