Fanuc Alarm 5400 SPL:ILLEGAL AXIS COMMAND (M series)
Fanuc Alarm Description
An axis specified for spline interpolation or smooth interpolation is incorrect. If an axis that is not the spline axis is specified in spline interpolation mode, this alarm is issued. The spline axis is the axis specified in a block containing G06.1 or the next block. For smooth interpolation, the axis specified in G5.1Q2 is incorrect.