To understand the complexity of relocking, one must first understand the bootloader's role. The bootloader is the first piece of code that runs when a device is powered on. Its primary directive is to verify the integrity of the operating system it is about to load. Manufacturers like Sony implement a secure boot chain, often utilizing technologies like TrustZone, to ensure that only authorized, signed software runs on the device.
The "1662 patch" (often rolled out silently via security updates) does three things:
If a device was unlocked via an exploit prior to patch 1662, taking an Over-The-Air (OTA) update that includes the 1662 binaries will automatically re-lock the bootloader upon reboot. Because the underlying firmware is now custom (e.g., Magisk or a Custom ROM), the newly enforced secure boot will fail, rendering the phone unbootable until a factory reset or edl-flash is performed.
Before this patch, users could exploit specific flaws in the secondary bootloader stage to turn a "Bootloader Unlock Allowed: No" status into "Yes". The 1662 security update closes this gap, enforcing strict cryptographic handshake checks at the hardware level. The Unlocking Challenge Under Patch 1662
Many users think: "I want to sell my phone, so I should relock the bootloader to make it 'stock' again." se bootloader unlocking relocking 1662 patched
Unlocking will trigger a factory reset, erasing all internal storage. developer.sony.com Get the Unlock Code : Visit the Sony Developer World portal. Select your model and enter your (found by dialing ) to receive your unique unlock key. Enable Developer Options About phone Build number Toggle Settings Developer options USB debugging OEM unlocking Fastboot Mode : Power off your device. Hold the
Relocking the bootloader is a simpler process. After you have reverted to a stock ROM, you can use the same tool:
A binary flag ( 0x00 for locked, 0x01 for unlocked) read by the Little Kernel (LK) or primary bootloader stage during power-on. The Unlocking and Relocking Cycle
Attempting to bypass the 1662 security layer with outdated software tools can lead to irreversible hardware failure. Keep the following rules in mind: To understand the complexity of relocking, one must
Historically, you could attach a Mi Account to a phone, wait 7 days (168 hours), and unlock. The "1662 patch" changed that. Manufacturers realized that resellers were bulk unlocking phones to install adware or fake global ROMs.
If you have tried to unlock the bootloader on a recent device only to be met with an error mentioning "Token verification failed (1662)" or "Account not authorized (1662)," you have hit the new Silicon-Era (SE) wall.
: Once received, execute the final fastboot command: fastboot flashing unlock Use code with caution.
Below is a suitable for a blog, tutorial, or forum post. Manufacturers like Sony implement a secure boot chain,
Note: On 1662 firmware, you must accept the warning prompt on the device screen using the hardware volume keys.
Real-time RPMB hardware hashing; invalid configurations trigger a self-wipe.
(fingerprints and facial recognition profiles).
On a 1662-patched device, treat "Relock" as "E-waste activation."