Editors' Note: This story was updated on Dec. 2 with news of Apple's tool for eligibility.
As we reported last month, Apple is starting a battery replacement program to fix a bug that's causing certain iPhone 6s models to randomly shutdown due to faulty batteries. Now, we've learned that you can check whether or not your iPhone qualifies for this new battery program, using a new tool made available from Apple itself.
9to5Mac reported that you can check the characters in the "4th and 5th" position match an item in a list below to see if your iPhone 6s qualifies. The lack of a source for this information, though, gave me doubt, so I reached out to Apple Support and an agent told me that you can't check it yourself.
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The fastest way to find out is to visit this page and enter your iPhone's serial number into the form at the top and click Submit. You can find the serial number by opening Settings, tapping General and then tapping About.
Alternatively, you can find out your device's status by visiting Apple's Support page. Once you're there select iPhone, select Battery, Power & Charging, select Unexpected shutdown or restart, select No and select a customer support option such as Chat. This way you can read the serial number to an Apple advisor to confirm its eligibility.
To prepare your iPhone for the battery replacement, first backup the handset to iTunes or iCloud. Then, disable Find My iPhone by opening Settings, tapping iCloud, tapping Find My iPhone, turning off the switch next to Find My iPhone. Your iPhone will then prompt you to enter your iCloud password and tap OK.
The battery replacement program covers "iPhone 6s batteries for 3 years after the first retail sale of the unit," so you don't need to worry about the expiration of your warranty or AppleCare. That said, using the program won't extend your warranty.
While we bet users would be excited for the chance to solve this wonky problem, Apple notes that the battery malfunction "is not a safety issue" (see what they did there?) and that it "affects devices within a limited serial number range that were manufactured between September and October 2015." So don't worry about rushing down to your nearest Apple store (or Authorized Apple Service provider) immediately.
Before going to a store for the program, call first and ask about the status of the battery replacement program for that store. It appears that not all stores have the program up and running at the moment, and we've seen reports that some stores have the replacement battery parts on backorder.
What's causing the problem? Apple hasn't said officially, though Business Insider reports that a note on Apple's Chinese language website blames the problem on a battery component being exposed to ambient air for too long before it was assembled.