[Tips]Unlocking the Mi4c BOOT LOADER without verification by Xiaomi
This evening I had the same problem like many of you and I just did not want to wait 2-3 weeks for the unlock code from Xiaomi. I went through a lot of threads and different forums to create this guide.
Step 1 is optional: I was not sure, if I could use the "fastboot oem edl" command in a higher version of MIUI... feedback required. Thus following is a list of known Xiaomi ROMs which support this procedure:
If you are using one of the following ROM versions, you should be able to unlock the device easily with the provided guide. However, I have messages that the versions don't work with higher MIUI ROM versions.
V6.1.21 (Download link above)
Not confirmed (?)
No information on this
(Optional) Downgrade your Mi4c by flashing any image from the list above via the "Updater" app (use top right icon to select image).
Reboot into fastboot mode (Power + Vol Down) until you see the MIUI rabbit and "FASTBOOT"
Command: fastboot oem edl (this brings your device in a kind of emergency recovery state) -> the device does only show a black screen. Do the next step.
Use MiFlash to flash 6.1.7 image (Browse -> select the "images" directory of the 6.1.7 package and start flashing)
Reboot until 6.1.7 is completely loaded (at this point it may take a while)
Reboot into fastboot mode (Power + Vol Down)
Command: fastboot oem unlock -> at this point you should have an unlocked bootloader.