This is a crucial step often missed. The USB drive must be formatted to the file system. If it's NTFS or exFAT, your head unit will not be able to read the update files.
Release the button once the screen flashes or the recovery text appears. The system will detect the update.img on the USB drive and install it automatically.
Before you update (preparation)
The K2001N is not a single, standard product. It is a platform manufactured under various brand names by different companies, each with its own specific firmware. Before looking for any update, you must identify your exact model details from the "System Info" screen.
After the update completes, you will need to reconfigure some settings: K2001n Firmware Update Android 11
Firmware updates wipe user data. Backup:
Comprehensive Guide to K2001n Firmware Update Android 11: Boost Your Head Unit This is a crucial step often missed
—the XDA Developers Android Head-Units forum, 4pda.to (Russian), and ZNDS (Chinese) are active communities where K2001N owners share firmware links and troubleshooting advice. A user found that "there is a chance someone might be working on a custom ROM for your unit" by following these communities.