Unlocking the bootloader on Nubia Z80 Ultra NX809J with generic commands is not possible. Methods that worked on older REDMAGIC devices (for example, using an engineering ABL) are not sufficient for Nubia Z80 Ultra NX809J — the device’s secure‑boot architecture and configuration partitions block those approaches. This article explains How you can unlock bootloader on Your Nubia Z80 Ultra NX809J
What is an engineering ABL (eng ABL)?
An engineering ABL is an engineering/debug build of the ABL (Android Bootloader Loader). On some earlier REDMAGIC devices, obtaining and flashing an eng ABL allowed developers to enter an engineering environment that made bootloader unlock or further modifications possible. That technique relied on the device trusting the flashed ABL within the existing signature/verification chain.
Requirements
How to Unlock bootloader on Nubia Z80 Ultra NX809J:
- » Open QLM Auto Tool & Login
- » Select Brand Nubia & Model NX741J
- » On the phone, enable USB debugging + OEM unlock from Developer Options
- » Connect the device to the computer in normal mode using a USB cable
- » Click ‘Unlock Bootloader’
- » Wait until successful; once the device is on the logo, plug the device back into the computer in EDL mode
- » Now wait until the tool restores your device functions
- » Once done, the device will start with a yellow bootloader unlock warning
- » Format data in recovery mode & reboot — success
How to Root Nubia Z80 Ultra NX809J
- Download Nubia Z80 Ultra NX809J stock firmware (must match the installed firmware version)
- Extract init_boot.img from it
- Move init_boot.img to the phone storage
- Install the prepared root app, Magisk or Sukisu Ultra
- Click Install, browse, and select the file we moved
- After patching the file, move it back to the PC
- Now flash the file:
fastboot flash init_boot init_boot.img
fastboot reboot
Your device is now successfully rooted…