Asus WS C246M PRO Manual page 27

7. CATT ERR LED (CATTERR1)
The CATT ERR LED indicates that the system has experienced a fatal or catastrophic
error and cannot continue to operate.
8. USB BIOS Flashback LED (FLBK_LED)
The BIOS Flashback LED flashes when you press the BIOS Flashback button for BIOS
update.
ASUS WS C246M PRO
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