Reports are making the rounds about a bug in iOS 17 and iPadOS 17 that causes devices to shut off at night and restart in the morning. The giveaway is being asked for your passcode because the iPhone or iPad has restarted. For confirmation, check Settings > Battery > Last 24 Hours, which will show a gap if the device was dead to the world overnight.
Doug Miller broached the topic on TidBITS Talk, sharing screenshots from his iPhone and iPad, both of which decided to shut down for hours on the same night. Notice that the iPhone screenshot on the left has a pause icon and lacks the green background and lightning bolt of the iPad screenshot that indicates charging. But the graph shows that the iPhone must have been charging because it’s fully charged when it restarts around 7 AM.
My iPhone suffered the same problem the next day, but my screenshot looks like Doug’s iPad screenshot in terms of icon and background, so it doesn’t add anything new. In contrast, Dana Schwartz posted a screenshot that shows the pause icon and white background along with the comment, “Charging was on hold due to iPhone temperature.” Dana said the iPhone was sitting bedside charging, just like every other night, so there’s no external reason it should have overheated. Notice that when the graph resumes, the battery level is higher than before the pause but not fully charged. The differences suggest that the bug may have multiple triggers or effects depending on other variables.
It’s odd that the bug hit so many people in the last week, and while most were running iOS 17.0.3, plenty were still using earlier versions of iOS 17, and one person experienced it with the developer beta of iOS 17.1. A very few people claim they’ve seen it in earlier versions of iOS, but such reports are exceptions.
For many people, these restarts aren’t all that problematic. I mostly don’t care what my iPhone does or doesn’t do while I’m asleep as long as it’s fully charged and ready to use when I wake up. However, some have missed alarms, and calls that would have woken you up could be lost. If you have a can’t-miss alarm for an early morning flight or essential meeting, set a backup on another device until Apple addresses the bug. We hope that happens soon.