Apple’s annual October hardware event wrapped late last month with the announcements of a new MacBook Air and a revamped Mac mini. Both computers, like the newest MacBook Pro and last year’s iMac Pro, come equipped with Apple’s security-focused T2 chip. The T2 chip, which acts as a co-processor, is the secret to many of Apple’s newest and most advanced features. However, its introduction into more computers and the likelihood that it becomes commonplace in every Mac going forward has renewed concerns that Apple is trying to further lock down its devices from third-party repair services.

The T2 is “a guillotine that [Apple is] holding over” product owners, iFixit CEO Kyle Wiens said. That’s because it’s the key to locking down Mac products by only allowing select replacement parts into the machine when they’ve come from an authorized source, a process that the T2 chip now checks for during post-repair reboot. “It’s very possible the goal is to exert more control over who can perform repairs by limiting access to parts,” Wiens said. “This could be an attempt to grab more market share from the independent repair providers. Or it could be a threat to keep their authorized network in line. We just don’t know.”

Apple confirmed to that this is the case for repairs involving certain components on newer Macs, like the logic board and Touch ID sensor, which is the first time the company has publicly acknowledged the new repair requirements for T2-equipped Macs. But Apple could not provide a list of repairs that required this or what devices were affected. It also couldn’t say whether it began this protocol with the iMac Pro’s introduction last year or if it’s a new policy instituted recently.

Power of the T2 Chip

The T2 is a custom-designed component that performs, among other tasks, processing for Touch ID fingerprint data. It also stores the cryptographic keys necessary to securely boot the machines it runs on. Apple says the chip is critical to new features, too, such as enabling the MacBook Pro to respond to “Hey Siri” requests without requiring you to press a button. It also prevents its laptop microphones from being remotely operated by hackers when the lid of the device is closed. Effectively, the T2 chip is capable of communicating with other components in order to perform some of the most important and sophisticated tasks modern Macs are capable of.

But recent revelations about the T2 have Apple critics concerned that it could be used to further shut out DIY enthusiasts and third-party repair services. First revealed last month by MacRumors and Motherboard, both of which got their hands on an internal Apple document, the T2 chip could render a computer inoperable if, say, the logic board is replaced, unless the chip recognizes a special piece of diagnostic software has been run. That means if you wanted to repair certain key parts of your MacBook, iMac, or Mac mini, you would need to go to an official Apple Store or a repair shop that’s part of the company’s Authorized Service Provider (ASP) network. If you want to repair or rebuild portions of those devices on your own, you simply can’t at least, according to this document.

The parts affected, according to the document, are the display assembly, logic board, top case, and Touch ID board for the MacBook Pro, and the logic board and flash storage on the iMac Pro. It is also likely that logic board repairs on the new MacBook Air and Mac mini are affected, as well as the Mac mini’s flash storage. Yet, the document, which is believed to have been distributed earlier this year, does not mention those products because they were unannounced at the time.

Regardless, to replace those parts, a technician would need to run what’s known as the AST 2 System Configuration suite, which Apple only distributes to Apple Stores and certified ASPs. So any engineering shops and those out of the Apple network would be out of luck. As the document puts it:

For Macs with the Apple T2 chip, the repair process is not complete for certain parts replacements until the AST 2 System Configuration suite has been run. Failure to perform this step will result in an inoperative system and an incomplete repair.

Apple confirmed that the display assembly should not require the diagnostic tool. The T2 chip, a now-integral part of the Mac hardware and software ecosystem that Apple says enables all sorts of critical security functions. In that sense, running the software diagnostic suite on T2-equipped devices could simply be a way to ensure that all of the security-focused features enabled by the chip remain intact after repairs of, say, the logic board on the iMac Pro or the Touch ID board on the MacBook Pro. It’s certainly reasonable, but Apple’s lack of clarity on when, why, and to what extent it instituted the diagnostic tool requirement has led to confusion and concern.

Apple says that a vast majority of repairs can be conducted without needing the tool, and it’s certainly true that most Mac owners will never be in the position of needing to replace a logic board or Touch ID sensor on their own. Both components are parts Apple says only it distributes, while solid state drives on most modern Macs, like the new Mac mini, are not user replaceable because they are soldered either to other components or the housing unit.

So while Apple may not have initiated this protocol for all T2-equipped devices or simply doesn’t require it on used parts, the company’s confirmation that it nonetheless requires some form of proprietary software may add more fuel to the long-simmering repairability debate.

The fact that Apple is requiring for the diagnostic tool on all future logic board and Touch ID replacements may dramatically increase the likelihood that right to repair legislation passes and forces them to reverse course.”  “Locking down repairs is bad for consumers, bad for the environment, and bad for Apple.”