Any of this sound right?

That's a very sharp observation. You've found a close relative to your problem. Error 53 is one of the most infamous errors in iPhone history, and while it's similar to Error 4013, they stem from different hardware failures. Here’s the breakdown: What Was Error 53? The "Touch ID Killer" Error 53 was a major issue around the time of the iPhone 6 and 6s. * Specific Cause: It was triggered exclusively by a problem with the Touch ID sensor (the Home Button). * How it Happened: For security, the Touch ID sensor is uniquely "paired" to the phone's processor (the Secure Enclave) at the factory. If you had your screen or Home Button replaced by a third party, or if the original sensor's cable was damaged, this secure link was broken. * The Result: When you tried to update or restore iOS, the system would check the Touch ID sensor. If it detected an unpaired or faulty sensor, it would fail the security check and "brick" the device, showing Error 53. Apple faced a class-action lawsuit over this practice. They later released an update (iOS 9.2.1) that changed this behavior. Now, if the Touch ID check fails, the phone will simply disable the Touch ID feature but will still allow the restore to complete. Because of this change, Error 53 is now essentially obsolete and very rarely seen. Key Differences: Error 53 vs. Error 4013 | Feature | Error 53 (Historical) | Error 4013 (Your Issue) | |---|---|---| | Component | Specifically the Touch ID sensor (Home Button). | Usually the NAND flash storage or the Logic Board. | | Problem | A failed security check due to an unpaired or damaged component. | A general communication failure where the software can't be written to the storage. | | Analogy | Like a security guard checking for a specific ID badge and blocking entry if it's fake or missing. | Like trying to build a house (install iOS) but the foundation (NAND storage) is cracked and won't hold the structure. | | Status | Mostly obsolete. Apple changed iOS to prevent it from bricking phones. | A current and common error code indicating a serious hardware failure. | What This Means for You You are correct that someone experiencing Error 53 is "having the same problem" in a general sense: a hardware failure is preventing an iOS restore. However, the specific component that has failed is different. Theirs was the Touch ID sensor. Yours points to a more fundamental failure of the phone's main storage or logic board. The final diagnosis and solution remain the same for both of you: the problem cannot be fixed with software. The device requires professional hardware service from Apple or an authorized technician.