[Google Pixel 3 XL Questions & Answers] aguyfromsomewhereelse:
Not sure if this helps anyone else, I had my Pixel 3 XL just break.

Bootloader failed to verify/load image. Going into rescue mode didnt work. Fastboot was giving the same No response error

Fastboot command (flash:bootloader_b) failed: 'error getting device locked state No Response'

I tried to flash the bootloader

(env) ➜ platform-tools fastboot flash bootloader bootloader-crosshatch-b1c1-0.3-7065185.img

Sending 'bootloader_b' (8517 KB) OKAY [ 0.310s]

Writing 'bootloader_b' FAILED (remote: 'error getting device locked state No Response')

and i tried to unlock the bootloader

(env) ➜ platform-tools fastboot flashing unlock

FAILED (remote: 'Error getting device locked state No Response')

fastboot: error: Command failed

So i figured this thing was bricked so i started play around with every command to see if anything would work

(env) ➜ platform-tools fastboot update ~/Downloads/crosshatch-rq2a.210405.006/image-crosshatch-rq2a.210405.006.zip

--------------------------------------------

Bootloader Version...: b1c1-0.3-7241706

Baseband Version.....: g845-00173-210331-B-7249945

Serial Number........: 8BLY10DMG

--------------------------------------------

extracting android-info.txt (0 MB) to RAM...

Checking 'product' OKAY [ 0.058s]

Checking 'version-bootloader' FAILED

Device version-bootloader is 'b1c1-0.3-7241706'.

Update requires 'b1c1-0.3-7065185'.

fastboot: error: requirements not met!

(env) ➜ platform-tools fastboot flashing unlock

FAILED (remote: 'Error getting device locked state No Response')

fastboot: error: Command failed

(env) ➜ platform-tools fastboot oem fastboot oem

FAILED (remote: 'Invalid oem command fastboot')

fastboot: error: Command failed

(env) ➜ platform-tools fastboot oem ddrtest

FAILED (remote: 'error getting device locked state No Response')

fastboot: error: Command failed

(env) ➜ platform-tools fastboot oem

fastboot: usage: empty oem command

(env) ➜ platform-tools fastboot oem citadel state

FAILED (remote: 'failed to get citadel state No Response')

fastboot: error: Command failed

(env) ➜ platform-tools fastboot oem citadel reset

OKAY [ 0.190s]

Finished. Total time: 0.190s

(env) ➜ platform-tools fastboot oem citadel state

(bootloader) Citadel state:

(bootloader) Version : 1

(bootloader) Bootloader state: 0

(bootloader) Production state: 1

(bootloader) Number of locks : 4

(bootloader) Lock[0]: 1

(bootloader) Lock[1]: 1

(bootloader) Lock[2]: 1

(bootloader) Lock[3]: 0

OKAY [ 0.151s]

Finished. Total time: 0.151s

(env) ➜ platform-tools fastboot flashing unlock

FAILED (remote: 'flashing unlock is not allowed')

fastboot: error: Command failed

(env) ➜ platform-tools fastboot oem citadel reset-locks

FAILED (remote: 'failed to reset citadel AVB locks Device Error')

fastboot: error: Command failed

(env) ➜ platform-tools fastboot oem citadel reset-locks

(env) ➜ platform-tools fastboot reboot

Rebooting OKAY [ 0.080s]

Finished. Total time: 0.080s

I finally got a different screen after

fastboot oem citadel reset

fastboot oem citadel state

fastboot oem citadel reset-locks

fastboot reboot

This gave me an android with a No connection error message and fastboot was no longer showing the device. I then hit power+up vol until it rebooted, hit power+down vol until it rebooted.. and it booted into Android!

hope something here helps someone else, I have no idea what i actually did but 🤷‍♂️