What causes FANUC alarm 1093?

A motion word such as X, Y, Z, or F was programmed in the same block as M99 while a macro modal call (G66) was active. The programmer mistakenly combined M99 with axis movement or other NC words thinking it would end the modal call and move simultaneously. A subprogram return block was copied from a non-modal context and used inside a G66 macro modal call without removing extra addresses. Feed rate F or miscellaneous function codes other than allowed addresses were included in the M99 block during active G66 state.

How do I fix FANUC alarm 1093?

1. Identify the block triggering the alarm by checking the program line number shown on the control screen and locate the M99 block in question. 2. Check if G66 macro modal call is active at the point of the M99 command. If G66 is active, M99 is treated differently than a standard subprogram return. 3. Remove any addresses other than O, N, P, or L from the M99 block. Move any required axis moves or other commands to a separate block before or after M99. 4. If axis movement is needed at the end of the macro, place it on its own block before the M99 return block so the control processes them separately. 5. Cancel the macro modal call with G67 before using M99 with additional NC words if the program logic requires it, then restructure accordingly. 6. After editing, dry run the program in single block mode to verify the alarm is cleared and the macro modal call behaves as intended.

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FANUC Controller

Program/G-code · Intermediate · 20-40 minutes

Alarm 1093

Fanuc Alarm 1093 - DUPLICATE NC-WORD AND M99

Alarm 1093 occurs when a macro modal call is active (G66 mode) and the program encounters an M99 block that contains additional address codes beyond the permitted O, N, P, or L words. The CNC detects illegal syntax where M99 is combined with axis commands, feed rates, or other NC words that violate the modal call return structure.

FANUCProgram/G-codeIntermediate20-40 minutes

1093

Fanuc Alarm 1093 - DUPLICATE NC-WORD AND M99

MACRO ALARM 1093

Root Cause Summary

Alarm 1093 occurs when a macro modal call is active (G66 mode) and the program encounters an M99 block that contains additional address codes beyond the permitted O, N, P, or L words. The CNC detects illegal syntax where M99 is combined with axis commands, feed rates, or other NC words that violate the modal call return structure.

Causes and Fixes

1
Press EDIT mode, navigate to PROGRAM > SEARCH and locate the block number shown in the alarm message. Examine the M99 block for any address codes other than O, N, P, or L.
2
Verify G66 modal call state is active by reviewing preceding blocks for G66 (modal macro call start) without a corresponding G67 (modal call cancel) before the M99.
3
Remove all illegal address codes from the M99 block. If axis motion or other commands are required, place them in a separate block before M99. The M99 block should contain only M99 and optionally O/N/P/L addresses.
Backup the original program to memory card before editing. Press SYSTEM > PARAM and verify parameter 3202 bit 5 (macro modal call enable) is set to 1 if using G66/G67.
4
Reset alarm with RESET key, restart program from a safe position before the G66 call using block search or manual repositioning. Verify the M99 now executes without alarm.

DIY Feasiblehigh confidence

Call a technician if:

·Parameter corruption suspected
·Multiple macro-related alarms occurring
·Program structure appears correct but alarm persists

Prevention

Always program M99 on separate block in macro subprograms
Use proper G66/G67 pairing for modal macro calls
Validate macro programs in single block mode before production
Maintain consistent macro programming standards

Common Mistakes

Programming coordinates with M99 in same block
Forgetting to cancel G66 modal call with G67
Using M99 incorrectly in main program instead of subprogram
Mixing incompatible address codes with M99 during macro execution

Related Alarms

1010 1011 1094 1095

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