This happened maybe like 6 months ago now but I was just thinking about it. I used to use an iMac but switched to a pc. One day it just turned on by itself - probably a couple of months after I stopped using it. Nothing was plugged into it, other than the plug for power. Nothing could have possibly pressed in the button on the back to turn it on, and I never did anything with the schedule stuff it said online. Also it was shut down, not on sleep. It just suddenly made the turning on sound mid day and to be honest it kinda scared me. I had to plug a mouse back into it just to shut it down. Anyone know what could have caused it?
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iMac turned on by itself
- Thread starter Dynamix123
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If you have that set to auromatically boot after a power failure, then it will boot when power is restored after a power failure - even if your Mac is turned off. The same thing can happen if it is plugged in to power, then the cord is unplugged for some reason. Plugging the cord back in will cause a boot, even if it was not powered on when the cord was unplugged. Just a setting in the system. Maybe it was plugged in to a power strip, and that power strip has a fault of some kind, power strip off, then power strip on, and your iMac boots.
Yep, a split second brown-out or black-out will cause this. Power doesn't have to turn off, just be low enough to trigger internal shut down.
If a recurring issue, have a talk with the power company.
When it happened to me a few years ago, my wife was ready to spend $20,000 to rewire the house ("that must be the problem!") till the PG&E tech went up the pole and found that squirrels had nearly eaten through one of the legs ("this is more common than people think") and the issue went away.
If a recurring issue, have a talk with the power company.
When it happened to me a few years ago, my wife was ready to spend $20,000 to rewire the house ("that must be the problem!") till the PG&E tech went up the pole and found that squirrels had nearly eaten through one of the legs ("this is more common than people think") and the issue went away.
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