I have an HTC One m8. It's running android 6.0.
If I attempt to boot up the phone it instantly shuts down when reaching the Google Logo. If I plug it in to a power source (AC/usb), it lets me boot, but once I unplug the power source it instantly shuts down.
The battery is indicated to be close to 100%.
This really does sound like a hardware issue with the battery, but I can still enter the bios (Power + Vol Down) and leave it open for a few hours without it dying (probably longer, didn't test it for longer). It only shuts down when I attempt to either boot or enter recovery.
I've already re-flashed the OS to stock with:
fastboot oem rebootRUU fastboot flash zip rom.zip fastboot reboot
So my question is: is this a hardware issue or software issue?
Is it because entering the bios requires such a minimal amount of energy, my device will allow me to enter it even when it's on extremely low battery? Or is it because the software is somehow incorrectly detecting the battery level and shutting down?