Flash LineageOS on Pixel 3a XL

It’s been a while since I flashed a custom ROM on an Android phone a few years back. Recently I needed to get an old Pixel 3a XL to work for a project and I have to say that installing custom ROMs has become much easier than before.

Steps:

Get your computer and phone ready for ADB. https://wiki.lineageos.org/adb_fastboot_guide
Follow the steps here provided by LineageOS: https://wiki.lineageos.org/devices/crosshatch/

Common Issues:

If your device is not showing when running the adb devices command, 9 out 10 times it’s either a driver issue or USB Debugging not properly enabled. When installing the driver, you have to make sure that you manually install the correct “Android Composite ADB Interface” rather than letting Windows automatically pick the driver.

e.g. in Device Manager, right click on your phone, select Update driver –> Browse my computer for drivers –> browse to the USB driver folder you just downloaded and choose: Let me pick from a list of available drivers on my computer, and pick Android Composite ADB Interface.

Upon successful installation, your phone should appear in Device Manager as Android Device - Android Composite ADB Interface instead of under Portable Devices or Universal Serial Bus controllers.

Additionally, fastboot flashing unlock doesn’t unlock the bootloader, make sure that Stay awake and OEM Unlocking are enabled under Developer options.

Other useful troubleshooting commands if your device is not showing under adb devices :

net stop winnat
net start winnat

adb kill-server
adb start-server

ADB Command Reference:

adb reboot bootloader
fastboot devices
fastboot flashing unlock
adb reboot bootloader
fastboot flash boot boot.img
adb sideload lineage-19.1-20230415-nightly-bonito-signed.zip
adb sideload MindTheGapps-12.1.0-arm64-20220605_112439.zip