Fanuc Alarm 47: ILLEGAL AXIS SELECT
Fanuc Alarm 47: ILLEGAL AXIS SELECT
Fanus Control Model: Fanuc Series 16, 18, 21, and the 16i/18i/21i Model C
Description
when the control system receives a command to move an axis that has not been properly defined, or when there is a conflict in the axis selection logic.
How to Fix Alarm
To resolve it, first verify the active G-code block for typos like an accidental “U” or “W” input. If the code is clean, check the CNC parameters against the machine’s original specification sheet to ensure the axis mapping remains intact.