You May Need to Replace Your IPhone 18 Pro Max.
Your iPhone 18 Pro Max can do a lot. It has a variable aperture, allowing you to control the amount of light reaching the camera sensor; it can charge to 50% battery in 15 minutes (with the right adapter, of course); and it can run all of Apple’s latest AI features thanks to the new A20 processor. But the 18 Pro Max is, first and foremost, a phone. If it can’t connect to a cellular network, you no longer have an iPhone, but essentially a souped-up iPod touch.
Unfortunately, this is exactly the situation some iPhone 18 Pro Max users have found themselves in. Despite being the “best” iPhone Apple has ever made, the company has confirmed that a “small number” of 18 Pro Max devices—specifically on AT&T—can no longer connect to cellular data, with only an “SOS” icon displayed on their screens. This is a serious issue: without cellular data, any apps or features that require internet will require a Wi-Fi connection, and you’ll lose the ability to make cellular calls entirely. The situation is so dire that some users may not even be able to call 911.
What if my iPhone 18 Pro Max can connect to a cellular network right now?
Just because your iPhone 18 Pro Max can connect to a cellular network doesn’t mean everything is fine. Even if your device is currently fine, you may still encounter this issue, and you’ll need to install the latest iOS 27.0.1 update, as well as the latest update from AT&T, to ensure your 18 Pro Max won’t be affected by these mysterious cellular issues in the future. Here’s what Apple told 9to5Mac in a statement : “We’ve identified an issue affecting a small number of iPhone 18 Pro Max users on AT&T that may result in loss of service and an inability to make calls. We released iOS 27.0.1 earlier this week and strongly recommend all iPhone 18 Pro Max users update now, and we’re also releasing a carrier settings update today. These updates, taken together, are intended to help prevent this issue from occurring.”
While you can always install iOS 27.0.1 via Settings > General > Software Update , Apple states that the carrier update will install automatically within the next 14 days. However, I recommend installing it manually by going to Settings > General > About . You won’t receive confirmation that the carrier update has been installed, but rest assured, this process will ensure it’s installed.
What should I do if my iPhone 18 Pro Max can’t connect to a cellular network?
Unfortunately, if your iPhone is already experiencing network connectivity issues, there’s no way to fix it. The above updates are only preventative; they can’t fix an iPhone 18 Pro Max that’s already unable to connect to a network. Unfortunately, the only solution is to exchange the device at an Apple or AT&T service center. The good news is that your store will exchange the device for free, as this is a hardware defect covered by the warranty.
It’s unclear why this issue only affects the iPhone 18 Pro Max and not the standard iPhone 18 Pro, and it’s unclear why it’s only seen on AT&T devices. A possible cause: the iPhone 18 Pro Max uses a Qualcomm modem, while the iPhone 18 Pro uses Apple’s proprietary C2 modem. It’s possible there’s a flaw in Qualcomm hardware specifically on the AT&T network.
This doesn’t mean the iPhone 18 Pro launch was uneventful—quite the opposite. It turns out that since the devices launched last month, Apple has encountered three more issues that have been reported by users. First, there was an issue with phones randomly rebooting after a failed Face ID attempt ; second, some users noticed their devices emitting crackling or popping sounds from the speakers. Finally, the exterior paint on some devices appears to have begun to fade. If you’ve updated your iPhone, hopefully everything is fine.