Hard bricked P20

[Curtricias]

I was on 9.0.0.197 firmware with my p20. Yesterday i tried to downgrade to 8.0.0.164. But when the device installed the firmware the installation stopped with a error.
After reboot the screen stayed black. The device is only detected as fastboot device.

So i bought credit and installed phoenix unlocker.

Opened the phone and managed to install bootloader with test point method.
Now bootloader screen works and tried to install the firmware again. 9.0.0.197.

When i juse DC Phoenix i get errors.

It alway stops with error in dts partition.

What am i doing wrong?

[dwalke15]

I have the same problem, but am a step behind - what board file did you use to install bootloader with test point method ?

[Curtricias]

I did'nt use a board file with the p20. Because there are'nt any. But when you choose a bootloader file you can simultaniously instaal stock firmware.

[dwalke15]

Success !!

I installed the bootloader, then stock firmware, using DC update process as you indicate above. Phone booted into eRecovery, but no further. Messed around for a while trying different firmware packages, but could not get past the boot screen.... If I tried straight eRecovery, always got the cannot find package error.

Changed my approach and set up a DNS server using firmware finder 2.11.29.1. eRecovery downloaded the firmware image (8.0.0.164) I had linked to on Team MT server and booted up as normal.

I then tried normal OTA update and it also installed and is running the latest version without any issue.

[Valdemaras]

I was on 9.0.0.197 firmware with my p20. Yesterday i tried to downgrade to 8.0.0.164. But when the device installed the firmware the installation stopped with a error.
After reboot the screen stayed black. The device is only detected as fastboot device.

So i bought credit and installed phoenix unlocker.

Opened the phone and managed to install bootloader with test point method.
Now bootloader screen works and tried to install the firmware again. 9.0.0.197.

When i juse DC Phoenix i get errors.

It alway stops with error in dts partition.

What am i doing wrong?

It doesn't seem that full stock rom's security version matches one that is in mobile and you can not flash different one over it. Need to try another firmware file in your case.

[Curtricias]

My P20 is unbricked!!

Thnx to help of a great man Ante0 .

After trying around and around and.......... this was my solution.

Downloaded dload firmware from androidhost.ru (8.1.0.165 C432)

Extracted update.zip + update.zip (customisation file).

Flashed bootloader with test point. Flashed oeminfo (modified by @AnteO to C432).

Put phone in upgrade mode.

Load files in in dc Phoenix

Installed files. Everyting went well execpt i had a error at the end of the installation of the first update.zip. 2 files were'nt installed (odm and product).

Installation went further without problems.

After reboot entered recovery and did factory reset.

Factory reset aborted at about 40 %....

Reboot ...... to erecovery......

Booted the phone to bootloader.

Flashed manually extracted ODM.img an PRODUCT.img.

Did factory reset 100%!

Reboot ...... ->>>> system!!!!!!

After complete setup automatic OTA update's recieved.

Now on 9.0.0.197

I want to thank the makers of DCPhoenix! Thank you fot your great program. Without this and the help of Ante0 this would never had an succesfull end!