What Is iPhone Error 53 and How Do You Fix It?

iPhone error 53 is a somewhat obscure problem that can cause an iPhone to not work. It's important to understand what it is, what causes it, and how to avoid it.

According to most reports, error 53 may occur under the following certain conditions:

• You own an iPhone 6, 6 Plus, 6S, or 6S Plus.
• The phone has iOS 8.3 or higher.
• You are trying to update the OS or restore the iPhone.
• A hardware repair was performed on the phone by someone other than Apple.
• You are trying to restore an iOS device using macOS Catalina 10.15, macOS Mojave 10.14 or earlier, or a PC with iTunes.

Causes of iPhone Error 53

In its error code page, Apple lumps error 53 in with several dozen other hardware problems and provides some generic suggestions. The current version of the page does not provide a useful explanation for what causes error 53, but an older version of the page claimed the following:

If your iOS device has Touch ID, iOS checks that the Touch ID sensor matches your device's other components during an update or restore. This check keeps your device and the iOS features related to Touch ID secure. When iOS finds an unidentified or unexpected Touch ID module, the check fails.

The important part is that the Touch ID fingerprint sensor is matched to the other hardware components of that device, such as the motherboard or cable that connects the Touch ID sensor to the motherboard. Apple prefers that Apple parts are used in an iPhone.

Apple has strict security around Touch ID. Touch ID uses fingerprint data, which must be protected for reasons of personal identity. It's also used to secure both your iPhone and Apple Pay data. An iPhone whose Touch ID unit does not match the rest of its hardware might have been tampered with, making it vulnerable to attack.

Since the components of the iPhone are aware of each other, getting a repair with components that don't match can cause iPhone error 53. For example, you may think you can repair a cracked screen or a broken Home button with any compatible part. According to Apple, you may get the error if those parts don't match—something many third-party repair shops may be unaware of.

If you see error 53, it's most likely because you had a repair done using parts that don't match each other.

How to Fix iPhone Error 53

Follow these steps to update or restore your device so that it works properly again.

1. Update the iPhone operating system. Apple fixed iPhone Error 53 with the release of iOS 9.2.1​. This update allows people whose phones have been hit with error 53 to restore the phone on their own, without contacting Apple or paying Apple for repairs.

2. Restore the iPhone. If updating iOS does not solve the problem, follow Apple's error-specific instructions for restoring a device with an iPhone Error 53.

3. Contact Apple support. If none of the above works, contact Apple customer support or make an appointment with an Apple Genius bar.