Apple released iOS 11.3.1 today, partially addressing an iOS 11.3 issue with iPhone 8 screens that were replaced by third-party repair shops. According to Apple, iOS 11.3.1 “addresses an issue where touch input was unresponsive on some iPhone 8 devices because they were serviced with non-genuine replacement displays.”
Reports two weeks ago noted that two different issues had appeared when iOS 11.3 discovered that replacement screens were installed in recent iPhones. One report revealed that iPhone 8, iPhone 8 Plus, and iPhone X models were experiencing ambient light sensor failures despite having been repaired with genuine Apple parts. Another report found that iPhone 8 phones using non-genuine Apple screens suddenly developed touchscreen issues when iOS 11.3 was installed.
Oddly, release notes provided with the iOS 11.3.1 update only mention the non-genuine screen bug with iPhone 8 models, while chiding users for considering unauthorized components or repair services. Apple tells users that:
Non-genuine replacement displays may have compromised visual quality and may fail to work correctly. Apple-certified screen repairs are performed by trusted experts who use genuine Apple parts. See support.apple.com for more information.
It’s unclear whether this or a future update will address the ambient light sensor issues identified on iPhone X, iPhone 8, and iPhone 8 Plus models with genuine Apple screens. Third-party repair shops have speculated that the sensor issue pops up only because they are unable to obtain and use an Apple repair tool that tells the iPhone to accept replacement parts without complaint.
iOS 11.3.1 is available now as a free over-the-air update using the Settings app, under General > Software Update.