This article describes possible solutions for an Android unit that is stuck during boot (may appear to no longer turn on).
System Update Failed to Complete
When a system update is available, it may include a firmware update that will install while an external power supply is attached after the system update is complete and the unit has rebooted. While the firmware (EC - Embedded Controller) is updating, the red power/charging light as well as the hardware Power button will not work. This can take 2 to 3 minutes to complete. If a firmware update is interrupted (e.g. the external power is removed while updating), the unit can get stuck at a BIOS/Boot menu or at a blank black screen (as if the unit is no longer powering on).
If this has occurred, attach an external power supply to the charging port and then attach a powered USB-C cable at the same time for only a second or two, in that order. If that does not revive the unit, then follow the steps below.
- Remove the cables.
- Press and hold the power button for up to 20 seconds (if the red light is on, wait until the red light stops blinking).
- Re-attach the external power supply (to keep attached) then the powered USB-C cable (to attach just for a second), in that order.
When the unit turns on (you can then detach USB-C cable) and completes the boot, log in and let the unit remain idle for 10 minutes to allow the update to complete. The powered USB-C cable only needs to be attached briefly to revive the firmware. It is not needed for charging or anything else after that.
If the unit still does not recover, you could try removing the battery and all cables (such as wall charger) so no power is attached, and leave out possibly even overnight. After that time, re-insert battery and attach wall charger. You may also need to briefly press the Power button.
System Locked During Reset
If you are attempting a factory reset on a device with a Google account, you will be prompted to enter the password for the account before the system can be wiped. This is a security feature referred to as Google FRP (Factory Reset Protection). For more details, see Help prevent others from using your device without permission.
General Ideas
More general ideas are provided at this web page.