Apple says a small share of iPhone 18 Pro Max phones on AT&T can lose cellular service, and that a phone the fault has already hit must be swapped for a new one because an update won't repair it. That's narrower than some headlines make it sound. Apple says it has seen the problem only on the Pro Max, and only on AT&T's network.
Owners say their phones drop into SOS mode, which cuts off calls, texts and mobile data. On Oct. 1 AT&T texted customers: "Some phones may be unable to complete calls/text/data, including to 911." The same message told them to update to iOS 27.0.1 "immediately". Apple's response comes in two parts: iOS 27.0.1 and a new AT&T carrier settings file. In a statement given to reporters, Apple said the two updates "together are meant to help prevent this issue from occurring". Apple presents the pair as a way to stop new cases, not as a cure for phones that have already failed.
If your phone still has signal, install the update from Settings, then General, then Software Update. The carrier file installs on its own within two weeks, or you can pull it in sooner from Settings, General, About. Already seeing SOS? Apple's advice is to reach Apple Support or AT&T, or walk into either company's store, to arrange a replacement. MacRumors reports that Apple Stores will replace affected phones for free. Apple's statement doesn't mention cost, AppleCare or proof of purchase, though, and Apple hasn't posted a support page for this specific fault.
Nobody has said what's causing it
Neither company has explained the outages. MacRumors put the question to AT&T, and AT&T pointed it back to Apple. One hardware difference stands out. A teardown by the chip analysis firm TechInsights found a Qualcomm Snapdragon X80 modem inside a US iPhone 18 Pro Max. Apple's US spec page lists its own C2 modem for the iPhone 18 Pro but leaves the modem line blank for the Pro Max. The Pro has stayed clear of the problem. That's a pattern, not proof: no one has tied the fault to the modem.
Apple calls the affected group a "small number" of users. MacRumors, which has been tracking the reports, says at least thousands of owners have described the problem on Apple's support forums, Reddit and its own forums, but nobody has published a firm count. The update has caveats too. Its release notes mentioned a Face ID fix and said nothing about cellular service, and some owners report losing signal after installing it.
We'll update this story as Apple or AT&T share more.
Has your Pro Max dropped into SOS mode, and how did the replacement go?
Sources
- 1.Apple confirms iPhone 18 Pro Max AT&T cellular issues, affected devices require hardware replacement · 9to5Mac
- 2.Apple Says iPhone 18 Pro Max Users With AT&T Cellular Issue Need to Have Device Replaced · MacRumors
- 3.AT&T Acknowledges iPhone 18 Pro Max Issues: Update 'Immediately' · MacRumors
- 4.Apple and AT&T Have Yet to Explain Cause of iPhone 18 Pro Max Issue · MacRumors
- 5.Apple confirms iPhone cellular issue, admits affected units can't be fixed · Macworld
- 6.Teardown confirms US iPhone 18 Pro Max lacks Apple's C2 modem · AppleInsider
Reported by the WattsUpNext desk from the sources linked below. Spot an error? Tell us at corrections@wattsupnext.com.
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