Strange power issue with my 2013 iMac 27”
Experiencing a very strange problem with my iMac.
When I shut down or restart my iMac, I can’t turn it back on immediately. To start/turn on again, I’ll have to unplug the power cable from the wall then wait for 30-60 seconds before connecting the power cable back into the (wall) power then it will turn on. Sometimes it powers off suddenly while the computer is in use.
Have no idea what the problem is but looks like it needs some kind of power “reset”. But that doesn’t explain why it shuts off suddenly sometimes.
Spoke to Apple on the phone and they asked me to try the following commands which I did but the issue still exists.
- Option 1: Shift+Ctrl+Option+Power for 10 seconds
- Option 2: CMD+Option+P+R until the second startup noise
Hope it’s nothing serious as in something to do with main circuit or motherboard.
Please suggest any solution if you have come across this issue before.
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3 件のコメント
Just a thought here, wondering if the backup button battery may be dead: try disabling the "Set time and date automatically" option—to prevent OSX automatically correcting if it finds a network connection—and see if after leaving unplugged for a while, whether the time and date has been reset (to 1/1/80 I think) or is still current when you power up again. That may be a fair test of the battery (happy to be corrected if wrong).
It's a CR2032, on the back of the logic board on 2013 and later iMacs.
See this link: https://discussions.apple.com/thread/796... which might be relevant.
Guy
Guy Hemmings さんによる
Guy - A dead battery would not explain the shutdowns. Besides, the battery is only used when the system is unplugged (not getting any power). As long as the system is able to gain some power (vampire load) the system won't use the battery.
Dan さんによる
Thanks for the correction, Dan, and the update on the battery behaviour. G
Guy Hemmings さんによる