My OnePlus2 (I think using OxygenOS) displays start icons (normal logo and fastboot, depending on how I boot it), however, afterwards the screen always remains black, while the phone responds to key presses.
Booting in recovery mode starts up the phone too, but never displays anything.
I tried to clear the cache using
fastboot (following the fastboot-info on here), but get this response:
$ fastboot erase cache ******** Did you mean to fastboot format this ext4 partition? erasing 'cache'... FAILED (remote: device is locked. Cannot erase) finished. total time: 0.020s
When I tried to unlock, following the
-help suggestions, e.g.:
flashing unlock Unlocks the device. Allows flashing any partition except bootloader-related partitions.
But it doesn't work:
$ fastboot flashing unlock ... FAILED (remote: unknown command) finished. total time: 0.006s
And another command I read about seems disabled:
$ fastboot oem unlock ... FAILED (remote: oem unlock is disabled) finished. total time: 0.009s
Is there another way I can erase the cache using
adb? I hope clearing the cache might resolve the black screen issue on my phone.