Some iPhone 14 Pro and iPhone 14 Pro Max users are seeing horizontal lines flash across their device’s display when it is powered on. At this time, no reason for the issue or fix for it has been determined.
As originally reported by MacRumors, in one thread on Reddit, dozens of iPhone 14 Pro users are reporting that they’re seeing one or more green and yellow lines flash across the screen before disappearing a few seconds later when the device is being turned on. The users say Apple Support has informed them the issue is not a hardware defect but is instead caused by a bug in iOS 16.
According to users on Reddit, the Apple Support forums (1,2,3), and the MacRumors forum, the issue seems to have started following the iOS 16.2 update. However, some users report seeing the issue with earlier versions of iOS 16. At least one user says an Apple engineer informed them that Apple is working on a software patch to fix the issue, but the exact details are not known.
Apple is currently beta testing iOS 16.3, and the beta could include a fix for the issue. However, users will likely be forced to wait until early 2023 for the public release of iOS 16.3.