It has been several days since **Apple** acknowledged that some $1,299 iPhone 18 Pro Max devices on AT&T lose cellular service entirely, but it still has not disclosed the specific cause.
Key Points
Neither Apple nor AT&T has explained why some iPhone 18 Pro Max devices lose cellular service.
Devices that have already lost service cannot be restored with software, so they must be replaced.
Models sold in the U.S. use Qualcomm modems, but no evidence has emerged so far directly linking the issue to a modem defect.
Service outage on AT&T’s network
A follow-up report on the issue was published Monday, saying Apple had not responded to further questions about the cause of the outage. An AT&T spokesperson also referred questions to Apple and offered no separate explanation. The silence has continued since Apple’s official statement on October 2, when it acknowledged that “a small number” of iPhone 18 Pro Max users on AT&T were experiencing service disruptions.
Affected devices lose the ability to make calls, send texts, and use mobile data. On some users’ devices, the only thing left in the status bar at the top of the screen is “SOS.” Apple told reporters that the issue cannot be fixed with a software update, and that affected devices must have their hardware replaced through Apple Support, AT&T, or a store operated by either company.
Apple released iOS 27.0.1 on September 28, and AT&T issued a carrier settings update on October 2. Carrier settings are downloaded automatically over a period of up to 14 days, and Apple urged all iPhone 18 Pro Max users to install the update immediately. The two updates are intended to “prevent” the outage, Apple said.
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Claims that the Qualcomm modem is to blame remain speculation for now
The iPhone 18 Pro Max sold in the U.S. uses **Qualcomm’s** Snapdragon X80 modem, while models sold in other countries use Apple’s in-house C2 chip. The lower-tier iPhone 18 Pro uses the C2 chip worldwide, and no reports of the same issue have emerged for that model. Apple has said so far that “the issue has been confirmed only on Pro Max devices using AT&T’s network.”
Apple journalist **Michael Simon** pointed out that the iPhone 17 Pro lineup uses the same Qualcomm modem but has not seen similar cases, arguing that the issue is more likely rooted in a software configuration tailored to AT&T’s network. However, a follow-up report published Monday also cited views that the problem may be a hardware defect, given that a full device replacement is required. Still, information made public so far does not provide evidence identifying the modem as the direct cause.
Comparison with Apple’s repair and recall practices
Apple has yet to disclose how many devices have been affected by the defect. Even so, reports continue to emerge on Apple Support forums and various online communities of thousands of users complaining about service outages.
Some users say their cellular service cut out immediately after activation, while others report that the problem appeared suddenly after several days of use. The precise cause of the outage remains unclear.
Sales of the affected iPhone 18 Pro Max began about two weeks before Apple officially acknowledged the problem. Apple has previously offered free repairs and recall programs for iPhone defects. In 2021, it offered free repairs for some iPhone 12 models with no sound during calls, and in 2024, for iPhone 14 Plus models with a rear camera defect. However, no formal recall or special repair program has yet been announced for the current service outage issue.
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