Shutdown and immediately restarts
Hello there!
Excuse the bad grammar, I am dutch myself.
When I click the power button of my iMac it turns on just fine, but when I am at the desktop it randomly shuts off (withing 5 min, sometimes longer sometimes shorter) and immediately restarts to do the same thing again.
Sometimes when I leave it at the desktop it stays on and just works fine (browsing the web, accessing the finder etc…) until I shut down the Mac myself, only to repeat it the whole thing again when turning it on.
I was wondering if this behaviour is indiciative of a failing power supply? I’m not seeing any other graphical glitches and or io faults so I hope it’s not the logic board. I could also replace the hard drive but it boots into the desktop flawlessly everytime, so I’m also not sure if that’s the problem.
To summarize: sometimes it stays on and works perfectly until I turn it off myself, most of the time it shuts down within 5 minutes after booting and sitting on the desktop and then immediately restarts.
Thanks in advance!
I would also like to add that it seems work for longer when it’s been turned off for longer, implying it might be something overheating inside. How can I maybe verify?
3.4千 
1.1千 
2.6千 
2 件のコメント
Boot up, hold the "D" key on the keyboard, until it asks to select a language, and run the hardware test. This will tell you if something is failing.
Joe Hartwell さんによる
This gives me a spinning globe, and a drop down menu where I can select Wi-Fi around me. Eventually it stops spinning and the mouse will not respond implying it froze up. It doesn't turn off though.
I can also confirm that the problem is not due to overheating, as I was able to install temperature monitor applications during the period it stayed on. I tried with a new hard drive, but the issue persists which also excludes it as the culprit.
Daniel van Dam さんによる