Asus old Zenfone 5 & 6 soft brick

I like to share my encounter with this Zenfone old series Zenfone 5 and 6. At the time i hold this 2 phones it already cannot boot into android and is either stuck at ASUS logo boot screen or stuck at the ASUS loading screen.

I start with Zenfone 5 first. This Zenfone 5 is stuck at Asus loading screen when i get the phone. And this problem occur when the owner of the phone upgrade the firmware from Kitkat to Lollipop. This is a WW version by the way.

So what i do is, I download the latest lollipop firmware from Asus official web page, then i extract the fastboot and recovery from the zip file, then i start up my ADB tool and boot the Zenfone 5 in fastboot mode, flash the latest fastboot and recovery, then reboot into bootloader and select boot into recovery.

From recovery i once again use adb to side load the firmware and the phone install the firmware it self. When it finish, the phone can boot normally. Just a side down, the internal storage got wipe out, so there is no way to save all the picture or other contents when side load from adb.

For the Zenfone 6, the problem is very similar to the Zenfone 5. But this Zenfone 6 stuck at ASUS logo boot screen instead of loading screen. At first i use the same method try to bring the phone back, but this time cannot. While at side load, the zip file cannot go beyond 54%, and it will reboot itself.

So instead of side load lollipop firmware, i try to load a kitkat firmware. And this bring the phone to life. So i update the kitkat via OTA to the final and latest of kitkat version available, then i copy the lollipop firmware i download earlier into root storage of phone, and the phone just automatically install to the latest lollipop firmware.

Although the Zenfone 5 and 6 suppose to be same in all specs, but the way Asus do the ROM is one thing which make normal user a headache while want to upgrade to latest version. Even update through OTA will have the possibility soft brick the phone.

One can leave a comment below if is interest to know how to use ADB tool and sideload to revive a soft brick Zenfone.