For a non-removable battery; if your screen turns black or won’t turn on, battery replacement may not be needed. You might just need to soft reset your device. A soft reset won't erase the content on your device. You can soft reset your device even if the screen is black or the buttons aren't responding.
Note: Some Buttons, Settings, Menus, or Icons may differ from that of your device depending on your software version and wireless service provider.
Button Hold
Press and hold the Volume Down and Power keys simultaneously until the device reboots. Typically this will take 8 seconds.
Device Reset
Release the volume and power keys when you see the LG bootup logo display.
On Screen Message
Depending on the state of your device you may see it perform a screenshot and/or a pop-up as shown below. This is normal.
Note: If the device does not reset, plug the device in for an hour and attempt to perform the soft reset again.
Note: Some Buttons, Settings, Menus, or Icons may differ from that of your device depending on your software version and wireless service provider.
Reset Clock
Tap Settings
> Date & Time (may be found under General Tab). Tap to enable Auto-date & Time and Auto-time zone.
Google Play Services
Tap Settings
Update Apps
Open Play Store, then tap Menu > My Apps & Games). Tap Update All to update your apps, then restart your device.
