can't unlock bootloader

[kindren]

Hello everyone,

after spending hours on the internet researching and trying out stuff I'm pretty desperate.

Maybe you can help me:

I have bought a Google Pixel 3a in used condition and it seems like it has some special edition of GrapheneOS installed.

I wanted to remove this special edition but it's not possible to unlock the bootloader as I cannot enter the Developer Options because this special OS locked everything!

So long story short: how can I unlock the bootloader "remotely" without unocking the OEM-unlocking in the developer options?

I appreciate any help!

btw: also tried to adb sideload but it always ends up with:

E:failed to verify whole-file signature
Update package verification took 106.0 s (result 1)
E: Signature verification failed
E:error: 21

Install from ADB completed with status 2.
Instatalltion aborted

 

[V0latyle]

So long story short: how can I unlock the bootloader "remotely" without unocking the OEM-unlocking in the developer options?

You can't. OEM Unlocking toggles sys.get_unlock_ability which the bootloader checks when you try to unlock. If this is 0 (OEM Unlocking off) it is not possible to unlock the bootloader via fastboot.

Did you try enabling Developer Options by tapping Build Number 8 times?

 

[kindren]

Yes, this special OS is actually hiding the build number so I can't enable developer options!

 

[CoolKitty]

I haven't got any personal experience with Graphene OS but with a pixel phone, your best bet would be either the pixel repair tool or the android flash tool.
To my knowledge, you don't need a fully unlocked bootloader for the repair tool and I've used it to unbrick my 3a a few times, but it doesn't always help if the issue is somewhat more serious, unfortunately

 

[simplepinoi177]

I could be way off, but I remember back in with my Pixel 2 XL (Oreo), I believe there used to be a fastboot or adb command to toggle the OEM unlock status which would therefore allow to unlock the bootloader -- though I imagine that the OEM toggle is still ticked because a custom ROM is installed, but it might be required to allow USB Debugging (which is in the same settings as the OEM toggle so, you might not have access to it though). I'm unsure if this is true with the Pixel 3 and/or whatever Android OS version runs on it...