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Identify the program block triggering the alarm and note the line number (N-number) displayed with the alarm.

Check the chamfer value specified (,C or ,A parameter) and compare it to the total axis movement distance in that block.

Calculate if the chamfer dimension is less than half the movement distance for linear moves. For ,C value, ensure C < movement distance. For ,A angle, verify the resulting chamfer is achievable.

Reduce the chamfer value to be within acceptable limits (typically less than the shortest axis movement in the block) and re-run the program.

Always verify chamfer dimensions don't exceed 50% of the shortest programmed move to avoid geometric conflicts.

Review the alarm block and verify chamfering is only used with G00 or G01 linear interpolation commands, not with G02/G03 circular moves.

Confirm the chamfer format follows correct syntax: ,C_ for chamfer distance or ,A_ for chamfer angle, with no spaces and proper decimal point usage.

Check that chamfer commands are not used in single-axis moves or blocks without adequate two-axis movement to create a valid chamfer.

Chamfering requires at least two axes moving simultaneously to create the angled cut.

Correct the syntax or remove the chamfer command from incompatible move types, then verify the program in graphics mode before running.

Check if tool radius compensation (G41/G42) is active when the chamfer is commanded. Review parameter settings or disable compensation before chamfering.

Some Fanuc controls restrict chamfering while cutter compensation is active depending on parameter 5030 and 5031 settings.

Verify that incremental programming (G91) has sufficient movement values to accommodate the requested chamfer dimension.

Examine the blocks immediately before and after the chamfer command to ensure the tool path creates valid corner geometry (angle between moves should be less than 180 degrees).

Either modify the chamfer value, change to absolute programming (G90), cancel tool compensation, or restructure the tool path to create valid chamfer geometry.