Apple has clarified in a new support document on its Chinese website that random shutdowns that have been plaguing some customers may affect more iPhone 6s models than previously thought, saying a software update may fix the issue on units outside of iPhone 6s devices which were manufactured between September and October 2015 and for which it’s offering a free battery replacement program.
As first noted by Gizmodo, Apple wrote it needed additional diagnostic data to determine the exact cause of the problem.
Here’s Apple’s machine-translated notice:
Outside the affected batch, a small number of customers reported an unexpected shutdown. Some of these shutdowns may be normal, because the iPhone will shut down to protect its electronic components. To gather more information, we will add an additional diagnostic feature to the iOS software update that is released next week.
This feature collects a variety of information in the coming weeks that may help us improve algorithms for managing battery performance and shutdown operations. If such improvements can be achieved, we will deliver them through further software updates.
In other words, an upcoming iOS software update will contain additional diagnostic capability to help it gather information about the affected devices.
Should Apple determine that devices outside the certain serial number ranges are suffering from unexpected shutdowns due to an issue that can be fixed in software, then a patch will be delivered in future software updates.
Three weeks ago, the company put forth a worldwide free battery replacement program for iPhone 6s units manufactured between September and October 2015 that exhibit random shutdowns when the battery charge level falls below the thirty percent mark.
You can see if your phone is eligible for a free battery using Apple’s web tool.
A support document in Chinese posted four days ago explained that the problem stems from some battery components being overexposed to controlled ambient air before being assembled into battery packs, causing them to cut out.
“As a result, these batteries degrade faster than a normal battery and cause unexpected shutdowns to occur,” Apple writes, underscoring that “this is not a safety issue.”