[ Advanced ] Unlock the Bootloader

[Daphne]

Hello there !

I’m also in trouble, I think I made a mistake…

I forgot to turn on OEM unlocking before trying to launch the fastboot. I turn on the phone again to correct this, but then

aka
dm-verity corruption
Your device is corrupt
It can’t be trusted blablabla…

I still can go back to flashboot menu, but nothing happen with both platform tools r 33 and mediatek (I can’t run it at all) and now, I can’t even turn the phone on.

I’m a very beginner in this !

Thank you,
Daphné

[Sharad]

Hi @Daphne - welcome to Teracube forums. No worries - Please restore the factory firmware first using these steps. Just be careful to use the right firmware image (2022 vs 2021).

[Nellone]

Is there a way to do this on a mac? I’m have done the same thing

[Sharad]

@Nellone

Is there a way to do this on a mac

@Nellone - do you want to unlock the bootloader or do you want to restore the factory firmware?

The SP Flash software (required for restoring factory firmware) is only available on Windows and Linux.

[Nellone]

Restore to factory firmware. Ill find a friend’s windows computer to use no worries.

[Sharad]

FYI - we have also released an easier process to install factory OS.

[MichT]

The procedure doesn’t work for me. After pressing unlock, the phone reboots, however is still locked. There is also no “orange state” while booting.

I am on LineageOs 1.6-20221129238947 Android 11

What can I do?
Michael

[Saijin_Naib]

What procedure did you follow to get LineageOS on your device?

[MichT]

Thanks for coming back!
I used /e/OS Easy Installer - v0.17 on Linux ubuntu
This worked flawlessly, it was a very comfortable process.

I also followed every step of Sharads Tutorial and get every menue as described.

Any idea?

Yours
Michael

[Saijin_Naib]

I’m not sure how you have LineageOS if you used the /e/OS Easy Installer, so I think some details might be missing.

[MichT]

So, which exact procedure would you recommend to install lineageOs on teracube 2e 2022 to get the phone with unlocked bootloader?

I understand, that a recommendation does also not guarantee a success, however, I would really like to have an unlocked phone.

Yours
Michael

[Saijin_Naib]

I wouldn’t recommend following the official LineageOS documentation or trying to install LineageOS direct from the official website at this time as the 2e isn’t an officially supported target yet.

There is however, a build here on the Community that is made specifically for our 2E Emerald units:

[Advanced Users Only][Teracube 2e 2nd Batch (SN: 2021)] LineageOS 18.1 Beta [emerald]

NOTE: These builds ONLY WORK for the Teracube 2e 2nd batch (SN: 2021), and not 1st batch (SN:2020). Please read the differences here carefully and flash accordingly. If you are looking for Lineage for SN:2020 T2e, then click here. [image] LineageOS is a free, community built, aftermarket firmware distribution of Android 11, which is designed to increase performance and reliability over stock Android for your device. LineageOS is based on the Android Open Source Project with extra contrib…

However, you should be able to follow the /e/OS instructions to unlock the bootloader without issue, no matter what OS you intend to put afterwards.

https://doc.e.foundation/devices/emerald/install
Specifically the Unlock The Bootloader and OEM Unlock the Device sections, and I would then use whatever LineageOS install instructions that accompany the ROM you’ll be using.

[MichT]

I followed the advices on Enable USB Debugging and OEM Unlock

Everything works fine until the command “fastboot oem unlock” returns → FAILED (remote: unknown command)

“fastboot devices -l” returns the device and shows, that usb-connection is open.

Any idea?
Thanks for help, if possible.
Michael

[Saijin_Naib]

You should be able to unlock it if you follow the documentation I’ve linked. I’ve done it on multiple 2E devices without issue recently, so the instructions are still applicable/current.

[MichT]

Saijin, I originally used the Easy Installer method as recommended by this page:
https://doc.e.foundation/easy-installer

The Teracube 2e 2022 is explicitely supported by this method and it worked perfect on my phone.
Can you possibly explain, why the lineageOS stable obviously does not allow to unlock the bootloader?

Thank you.
Michael

[Sharad]

Hi @MichT - are you still having issues? If you are using /e/ OS, then your unit’s bootloader is already unlocked.

[MichT]

No, doesn’t work. I have tried installing several builds recommended here, but only have the button “OEM lock” in developer options visible in version LineageOS Android 11 1.6-r-20221129238947-stable-emerald . See screenshot.
I have followed all above steps carefully. They work, all data is deleted, as promised, but bootloader obviously still locked. When I try to install Battery Charge Limit App, it says, “root access denied”.
It’s a pity, because I want to upper-limit the battery charge to enlarge battery lifetime.

Any help apprechiated!
Michael

[Gagan]

Hi!

Can you please go to fastboot mode and let me know what the output of fastboot getvar unlocked is?

Regards
Malvi

[MichT]

Thank you for coming back, Malvi.

It says:
xxxx@xxxxxxxx:~$ fastboot getvar unlocked
unlocked: yes
finished. total time: 0.000s

[Saijin_Naib]

MichT, root access and unlocked bootloader are not the same thing. You’ll need to root the device.