- Go to https://passport.lenovomobile.com/wauthen3/wauth/jsp/register.jsp and register an account there, choose “Register via email address“.
- Then use only the Internet Explorer (if you’re on Windows…) and go to http://developer.zuk.com/bootloader
- DO NOT translate the page, open a second browser, where you can translate the page.
- Click on the button highlighted in the picture below:
- Do the required steps like enter model as Z2, enter the serial number. If the serial number is 8 digits then enter it as it is, else add one or more ‘zero’ at the end to make it 8 digits. After step 2 you are asked to log in, log in with the credentials that you provided during registration.
- After successful login the “unlock_bootloader.img” file will be sent to the provided email as an attachment. Download the file to a directory on local folder.
- Connect the phone to an USB port on your computer using its own cable.
- Using windows explorer go the directory where the adb.exe and the unlock_bootloader.img files are located. Shift + Right Click and choose “Open Command Window Here”.
- In the command window type “adb devices”, it should show a number. If it doesn’t, then see if USB driver is installed properly and adb.exe is in the current folder. Restart the PC and the phone and try again.
- Once device is detected, reboot it to bootloader mode by running “adb reboot bootloader”.
- Then to unlock, run “fastboot -i 0x2b4c flash unlock unlock_bootloader.img” and then “fastboot -i 0x2b4c oem unlock-go”. Warning!! this will erase the internal memory of the phone.
If you just wanted to unlock the bootloader then you just did it. If you want to install a custom recovery (TWRP) then go to the steps given below.
- You don’t need to ROOT your phone just to install custom recovery and ROM.
- Download the recovery from https://dl.twrp.me/z2_plus as given in the TWRP official site, save it to the same directory as ‘adb.exe’ and ‘fastboot.exe’ and rename it to ‘twrp.img’ just for convenience.
- While in the “bootloader” mode, run below commands:
- fastboot -i 0x2b4c flash recovery twrp.img
- fastboot -i 0x2b4c reboot
Now the phone will start to reboot; while booting up it’ll show a message to press any key for 5 seconds, press one of the volume keys. It will then go to a menu where you need to choose “Recovery” option using the volume +/- keys and press the power button to select it. Then it should go to the TWRP recovery. In case it doesn’t, reboot it again and follow the process. Once in TWRP the first question you’ll see is whether to keep it ‘read only’ or enable ‘Read Write’. It’s upto you, to be safe I kept ‘Read Only’ so that the partitions don’t get altered.
- Download the ROM and GAPP as given in the link above.
- While the device is in TWRP connect it to the PC with USB cable.
- Copy the ROM and GAPPS zip files into the phone.
- Disconnect the cable.
- Wipe Data, Cache and Dalvik Cache
Flash ROM and GAPPS
If one day you want to revert to stock ROM, then please follow the method here; it’s absolutely correct and I’ve used many times with expected results. However, I’m providing the sequence of steps below again for convenience:
a. Download Chinese ROM ZUI 1.9.044 from here. Extract to a folder and provide “ask.lenovomobile.com” as password if asked.
b. Download India ROM ZUI 2.0.093 from here. Extract to a folder and provide “ask.lenovomobile.com” as password if asked.
c. Assuming your PC has ZUK USB driver, ‘adb’ and ‘fastboot’ already installed. If not, install them and also download and install QPST from here.
d. Make sure your phone’s boot loader is unlocked. You can check that by rebooting to bootloader mode.
e. Run QFIL (the program in QPST package) on your PC.
f. Reboot EDL mode: Enable USB debugging on your phone, connect USB and issue command “adb reboot edl” from a command window on your PC.
g. Now QFIL should be able to see your phone as “QDLoader 9008” on some COM port.
h. Then follow the procedure here to flash ZUI 1.9.044. If you don’t find any “.mbn” files in the downloaded ROM directory then use the “*ddr.elf” file. Rest of the process should be as given in the link.
i. After a successful flash and the phone is rebooted into a Chinese ROM, just do some guess work, touch the “skip” option in Chinese in all initial setup screens (in top right corner). Finally again enable developer options and enable USB debugging. You’ll have to check some options before finding them, but some words like ‘USB’ and ‘ZUI’ etc. are in English and can be recognized.
j. Again do a “adb reboot edl” and flash the Indian ROM on top of the Chinese ROM. If QFIL flashing process fails then restart your PC as well and redo the process.
k. In my case after flashing the Indian ROM and a reboot and the initial configurations, it automatically detected the next update and notified me to download and install, which is 2.0.133.
Congrats, you’ve done it.
You can follow the method given in below screen shot to verify the status of your phone:
Here is the link to buy one, if you’re interested in this phone: