Weâ ll use ADB commands to reboot into fastboot mode and verify the bootloader status. Fastboot is a bootloader mode in Android that lets you check the bootloader state, among other things.

You boot into recovery mode, and then you can troubleshoot your problems. Most people never need to use it, but there are situations in which it can bring a malfunctioning Android device back to life.

Boot OnePlus 3/3T into fastboot mode either by long pressing the power button and then selection the Bootloader mode, or either pressing volume up + power button after turning off the device.

OnePlus is placing new restrictions on bootloader unlocking for certain users starting its Android 16 update which arrives later this year.