What causes FANUC alarm 412?

Incorrect G-code command in the program. Misspelled or unsupported G-code in the program. Attempting to use a G-code that is not available on the Fanuc control.

How do I fix FANUC alarm 412?

1. Review the program line by line to identify the G-code that is causing the alarm. Look for any typos or unsupported commands. 2. Consult the Fanuc control's programming manual to verify that the G-code being used is valid and supported by the specific model. 3. If the G-code is valid, check the program logic to ensure the G-code is being called at the appropriate time and in the correct context. 4. Try running the program in single block mode to isolate the problematic line and identify the specific G-code causing the issue.

FANUC codes

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FANUC Controller

Program/G-code · Intermediate · 15-30 minutes

Alarm 412

Fanuc Alarm 412 - ILLEGAL G CODE

This alarm occurs when an invalid or unsupported G code is used in the program. Correct the syntax or replace the unsupported code to resolve it.

FANUCProgram/G-codeIntermediate15-30 minutes

412

Fanuc Alarm 412 - ILLEGAL G CODE

ILLEGAL G CODE

An unusable or illegal G code was specified in the program. Check the program for invalid G code usage and verify the G code is supported by this control.

Root Cause Summary

This alarm occurs when an invalid or unsupported G code is used in the program. Correct the syntax or replace the unsupported code to resolve it.

Safety

Position error
Disconnect power to the CNC machine before performing any mechanical or electrical troubleshooting.
Be aware of potential pinch points and moving parts when working around the 4th axis.
Use caution when working with electrical components. High voltage can be present in the servo amplifier.
Ensure the 4th axis is properly supported before disconnecting any mechanical components.
Consult the machine's documentation before making any changes to the servo amplifier settings or parameters.
Lock out/Tag out procedures should be followed before any maintenance.
Ensure the machine is fully powered off and locked out before performing any inspections to prevent accidental movement.
Wear appropriate personal protective equipment (PPE) as moving parts may be involved.

Causes and Fixes

1
Locate the error
Check the alarm message for the line/block number and review that part of the program.
2
Fix the code
Correct the invalid G code or syntax error based on the control’s programming manual.
3
Test the program
Clear the alarm and run the program to confirm the issue is resolved.

DIY Feasiblehigh confidence

Call a technician if:

·If the alarm persists after program correction
·If the required option cannot be enabled without assistance

Prevention

Validate G codes against the control manual before loading programs
Use simulation software to catch errors before running on the machine
Always perform dry runs or single block execution when testing corrected programs
Maintain proper documentation of machine-specific G code limitations

Common Mistakes

Overlooking the specific block number in the alarm
Assuming all G codes are universally supported

Seeing Multiple Alarms?

Seeing another alarm with this one? Enter the code.

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Always verify with your machine manual or a certified technician before performing service procedures.