iPhone 18 Pro Max AT&T Bug Forces Hardware Replacement

Some iPhone 18 Pro Max owners on AT&T have lost the ability to make calls, send texts, and use mobile data. MacRumors reports that Apple told the site Friday that affected units must be replaced. A software update won't solve the problem.

Neither Apple nor AT&T has explained what causes the failure. AT&T directed MacRumors to Apple, which hasn't answered further questions.

How to avoid the problem

Apple says it has only seen the issue on the iPhone 18 Pro Max on AT&T. A "small number" of users are affected, though MacRumors notes that thousands have complained on the Apple Support Community and other online platforms.

If your phone still works, you can lower the risk by installing two updates.

First, install iOS 27.0.1. Open Settings, then tap General > Software Update.

Second, the carrier settings update for AT&T will arrive automatically within 14 days. To trigger it right away, open Settings and tap General > About.

Apple says these updates "are meant to help prevent this issue from occurring."

Possible connection to the U.S. modem

U.S. models of the iPhone 18 Pro Max use Qualcomm's Snapdragon X80 modem, while versions sold elsewhere use Apple's custom C2 modem. Whether this difference plays a role is unclear; Apple has not confirmed it, MacRumors reports.

If your device is already affected, Apple says it needs to be replaced. No other iPhone model or carrier is impacted.

• Apple
• AT&T
• cellular service issue
• iOS 27.0.1
• iPhone 18 Pro Max
• replacement