What causes FANUC alarm 075?

Attempting to save or overwrite a program number in the protected range (typically O8000-O8999 or O9000-O9999) which is reserved by the machine builder or Fanuc system. Trying to edit or register an encoded/encrypted program without entering the correct password first. Parameter 3202 bits are set to protect certain program number ranges and the operator is trying to write to those numbers. An MDI or external device is attempting to load a program whose number conflicts with a locked system macro program. The program number being registered already exists and program registration protection is active via parameter settings.

How do I fix FANUC alarm 075?

1. Check the program number you are trying to register or edit. If it falls in the O8000-O9999 range, choose a different program number in the O0001-O7999 range instead. 2. Check Parameter 3202 on the control. Bits 0 and 4 control protection for O8000-O8999 and O9000-O9999 ranges. If these are set to 1, those ranges are locked and you cannot write to them without authorization. 3. If the program is encoded and requires a password, enter the correct password through the program protection unlock procedure before attempting to open or edit it. Contact your machine builder if the password is unknown. 4. If you need to register a program in a protected range and have authorization, you may need to temporarily disable protection by changing Parameter 3202 with the key switch in the parameter write-enable position, then re-enable protection after. 5. If the issue is a duplicate program number conflict, list all programs in memory using the program directory and either delete the existing program first or choose a new unused program number. 6. If the password for an encoded program is lost, contact your machine tool builder or Fanuc support as there is no standard user-level workaround for encoded program access.

axismd.ai

FANUC Controller

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

Alarm 075

Fanuc Alarm 075 - PROTECT

Alarm 075 PROTECT occurs when attempting to register, edit, or delete a program number that is protected by parameter settings, or when an incorrect password is entered for an encoded (encrypted) program. This is a safety mechanism to prevent unauthorized modification of critical programs.

FANUCProgram/G-codeIntermediate15-30 minutes

075

Fanuc Alarm 075 - PROTECT

PROGRAM ALARM 75

Root Cause Summary

Alarm 075 PROTECT occurs when attempting to register, edit, or delete a program number that is protected by parameter settings, or when an incorrect password is entered for an encoded (encrypted) program. This is a safety mechanism to prevent unauthorized modification of critical programs.

Causes and Fixes

1
Press SYSTEM key, navigate to PARAM screen. Set parameter write enable (Parameter 0000 bit 0 = 1, or use the write enable switch on the control if available).
Changing parameters requires proper authorization. Document original settings before making changes.
2
Check Parameter 3202 (Program Number Protection range). This parameter sets the lower limit of protected program numbers. Programs from this number to O9999 are typically protected.
3
If the program you are trying to register falls within the protected range, either use a program number below the 3202 value, or modify Parameter 3202 to exclude your target program number.
4
After parameter modification, set parameter write protect back on (Parameter 0000 bit 0 = 0) and reset the control with RESET button. Re-attempt program registration.

DIY Feasiblehigh confidence

Call a technician if:

·Password recovery needed for critical encoded programs
·Parameter protection requires management override
·System program modification needed

Prevention

Document all program passwords securely
Use consistent program numbering outside protected ranges
Regularly backup unprotected versions of critical programs
Train operators on protection parameter meanings

Common Mistakes

Assuming all programs can be edited regardless of protection
Not checking parameter 3200-3210 range before program operations
Using system program numbers for user programs
Ignoring PROTECT status indicators in program lists

Related Alarms

074 076 078

Seeing Multiple Alarms?

Seeing another alarm with this one? Enter the code.

Get machine-aware diagnosis

AxisMD logs alarms against your actual machines, tracks patterns, and gives AI context your manual doesn't have.

Start free

Was this guide helpful?

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