Go back to the main menu and open the newly unlocked Developer options .
Ensure your ROG Phone 3 has at least 50% charge to prevent accidental shutdowns.
Ensure your ROG Phone 3 has at least 50% battery life to prevent it from shutting down mid-process. how to open fastboot mode on asus rog phone 3
: In Settings > System > Developer Options , toggle on USB Debugging .
Plug your ROG Phone 3 into your computer using the original Type-C data cable. Go back to the main menu and open
Tap and select Bootloader (Fastboot) from the pop-up options. Navigating and Exiting Fastboot Mode
Use a high-quality USB Type-C cable (preferably the original one included in the box). how to open fastboot mode on asus rog phone 3
Simultaneously press and hold the Volume Up button and the Power button.