There’s finally some good news for iPhone 6 owners who have been plagued with a mysterious bug that suddenly shuts down their phone. After months of downplaying the problem, Apple this week offered some details about the defect—and, better yet, says it found a way to fix 70% or 80% of the affected phones.
For those who haven’t read about this, the problem first appeared in the fall of last year, and affected many iPhone 6 and iPhone 6s models. It resulted in the battery charge level abruptly plunging from levels over 50% to 1% or else the phones would inexplicably turn off altogether—only to display charge levels of 20% or more as soon they were plugged in again.
The issue is a major nuisance because it’s so unexpected, sometimes leaving iPhone users (including me) stranded without navigation or communication tools in unfamiliar places. Meanwhile, Apple’s response has been cryptic, to put it politely. Last year, the company announced a replacement battery program for a limited number of iPhone 6s models, while only conceding that a “small number” of other customers were affected by the shutdown program.
As I earlier reported, there’s evidence to suggest Apple’s “small number” in reality amounts to millions of iPhone owners, who have been vocal about the problem and the company’s failure to come clean about it. But the good news, as noted above, is Apple has finally offered up some new information.
The gist of it is that the company says its most recent software update, iOS 10.2.1, is putting an end to the shutdowns in many cases. In an email to Fortune, a spokesperson wrote (emphasis mine):
With iOS 10.2.1, Apple made improvements to reduce occurrences of unexpected shutdowns that a small number of users were experiencing with their iPhone. iOS 10.2.1 already has over 50% of active iOS devices upgraded and the diagnostic data we’ve received from upgraders shows that for this small percentage of users experiencing the issue, we’re seeing a more than 80% reduction in iPhone 6s and over 70% reduction on iPhone 6 of devices unexpectedly shutting down.
We also added the ability for the phone to restart without needing to connect to power, if a user still encounters an unexpected shutdown. It is important to note that these unexpected shutdowns are not a safety issue, but we understand it can be an inconvenience and wanted to fix the issue as quickly as possible. If a customer has any issues with their device they can contact AppleCare.
Tech news site TechCrunch interpreted these comments to mean that the software update changes how the phone’s battery draws power, avoiding surges that force the devices to shut down. This makes sense and is consistent with what I’ve previously reported—that the recent shutdown phenomenon appears to have been introduced by Apple as a circuit breaker of sorts to protect vulnerable batteries.
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It’s also worth noting that, in my case, the solution does appear to be working. Since I installed the 10.2.1 update, which came out in late January, I can’t recall my iPhone 6 shutting down unexpectedly (though during this time I have also been neurotic about plugging in my phone whenever possible to maintain a high level of charge).
Fortune reached out to an Apple spokesperson for more details, including whether future updates might help the remaining phones still vulnerable to shutdowns, but has yet to receive a response.
So for those of you still experiencing the shutdown problem, the best thing to do is make sure you’ve installed the update, if you haven’t done so already. And if you’re one of the unlucky ones for whom the new update is not a solution, it might be worth asking Apple for a new battery.