This quick guide shows how to Boot Asus Zenfone 2 ZE551ML into Recovery Mode and Fastboot Mode (Bootloader Mode) to wipe cache partition, factory data reset, ADB Sideload, wipe Dalvik cache and for flashing firmware.
The Fastboot Tutorial will show you the easiest way to access the hidden model called fastboot. Check out the secret combination of keys that will boot your device into fastboot.