Day034 — fixing a boot loop on Nexus 5x
I got a nexus 5x as my daily driver. I am always keen to try the latest and greatest Google has to offer so I have joined the beta program since Android Nougat. Android O is just released on the beta program last week. I downloaded it immediately to try out the new setting page layout, faster boot time, etc. However, I found that my apps are not playing well with the new OS. They become quite laggy when I switch between apps and deleting text on the inbox app. No doubt it is caused by the newly installed OS so I decide to factory wipe the phone and see if it helps.
On a side note, I feel kind of glad that I got to wipe my phone. I like to install apps I think it is interesting from the play store’s recommendation section. I will play it a little bit, and then forget it ever exist on my phone. In this wipe, I got to uninstall them all and stop them from using my precious RAM in the background. Think of it as a detox for your phone. It is so pleasant.
Back to the main course. I factory wipe the phone by going into the “back up” section in the setting and select the option of “erase everything”. However, it is the moment that all things go down hill. After the wipe is done and the phone restart itself, it got stuck at booting animation. Whenever the four colourful dot animation in the booting starts playing for a while, it stops for a second and then reboot again. I can no longer boot into the system using the conventional method.
One of the solution that first came to my mind is to go to the recovery mode and implement factory wipe there. After a power off, pressing power button and volume button down at the same time allow you to enter the bootloader mode. I use the volume keys to navigate to the “recovery mode” option and power button to enter. When the screen showing “no command” is shown, hold the power key and press volume up to enter command menu. Use the volume keys and power button to choose “factory wipe” and “cache wipe”. However, it turns out it does NOT work so I move on to the next method.
The next method I tried is to flash a new OS onto the phone. I downloaded the android O preview image from below URL.
Instructions for downloading and installing Android O Developer Preview device imagesdeveloper.android.com
And, I followed below instructions to do the flashing.
These files are for use only on your personal Nexus or Pixel devices and may not be disassembled, decompiled, reverse…developers.google.com
The problem is my phone is locked. I tired to use the “unlock” command:
fastboot flashing unlock
It comes to me that I did not enable “allow oem unlocking” in my phone’s developer settings. I could not “remote” unlock the phone from my computer using that command so that method does not work.
Finally, I found that sideload the OTA image is the answer I have been looking for half a day. The instructions are written here.
After I downloaded the OTA image and sideloaded it as the instruction stated, it WORKS. Notice that my phone is in locked state and the sideloading OTA image still works under that condition.
I tried some adb commands to copy all files on my phone to my computer. I only backup some important folders, Whatsapp (so that I don’t have to downlaod them all from my google drive backup), Telegram, Download and DCIM. Other folders than that are not backuped as I don’t think they make any good to me.
adb pull /sdcard/DCIM/ C:\