March 25, 2026 Shina Lin

FANUC Alarm Codes

Complete FANUC Alarm Code List, Causes & Troubleshooting Guide

FANUC robots are widely used in industrial automation, but when an alarm appears, production can stop immediately. Understanding FANUC alarm codes is critical for fast troubleshooting and minimizing downtime.

This guide provides a structured overview of FANUC alarm codes, including:

Alarm categories (SRVO, SP, SYS, etc.)
Common error causes
Step-by-step troubleshooting
Recommended replacement parts

What Are FANUC Alarm Codes?

FANUC alarm codes are system-generated messages that indicate errors in robot operation. These alarms help identify issues related to motion, hardware, communication, or system faults.

FANUC alarms are typically grouped into categories such as:

SRVO (Servo Alarms) – motion and axis-related issues
SP (Spindle Alarms) – spindle or drive system faults
SYS (System Alarms) – controller-level errors
INTP (Interpreter Alarms) – program execution issues

FANUC Alarm Code Categories

SRVO Alarms (Servo Errors)

Common symptoms:

Robot cannot move
Axis locked or vibrating
Collision detected

Typical causes:

Servo motor overload
Encoder failure
Drive unit malfunction

👉 Example alarms:

SRVO-050 Collision Detect
SRVO-021 Servo Alarm

SP Alarms (Spindle & Drive Errors)

SP alarms are related to spindle systems and drive units, commonly found in CNC-integrated FANUC robots.

🔧 FANUC SP9000 Spindle Alarms – Complete spindle alarm series, causes, and repair solutions
🔧 SP9010 Spindle Alarm – Common spindle fault and troubleshooting steps

SYS Alarms (System Errors)

Common symptoms:

Controller not booting
Unexpected shutdown

Typical causes:

Hardware failure
Memory issues
Power supply faults

INTP Alarms (Program Errors)

Common symptoms:

Program stops unexpectedly
Execution errors

Typical causes:

Invalid instructions
Logic errors
Data issues

Common FANUC Alarm Codes (Quick Access)

Below are some of the most frequently searched FANUC alarms:

SRVO-050 Collision Detect
SRVO-021 Servo Alarm
SP9004 Spindle Alarm
SYS-037 System Error
FANUC SP9000 Spindle Alarms

How to Troubleshoot FANUC Alarm Codes

Follow this structured approach:

Step 1: Identify the Alarm Code

Check the controller screen or alarm history.

Step 2: Understand the Alarm Category

Determine if it is:

Servo-related
System-related
Program-related

Step 3: Inspect Key Components

Focus on:

Servo motors
Encoders
Cables
Drive units

Step 4: Reset and Test

Clear alarms
Restart the system

Step 5: Replace Faulty Parts

If the alarm persists, hardware replacement is required.

High-Failure FANUC Components

From real maintenance cases, these components fail most often:

Teach Pendant

Screen failure
Keypad issues

Encoder Units

Position feedback loss
Signal errors

Servo Drives

Overheating
Internal faults

Robot Cables

Wear from repeated motion
Internal wire breakage

👉 Recommended parts:

FANUC Alarm Codes by System

To speed up diagnosis, alarms can also be grouped by system:

Motion system → SRVO alarms
Spindle system → SP alarms
Controller system → SYS alarms
Software system → INTP alarms

Related Resources

Explore more troubleshooting guides:

Conclusion

FANUC alarm codes are essential for diagnosing robot issues quickly and accurately. By understanding alarm categories, root causes, and repair solutions, you can significantly reduce downtime and improve maintenance efficiency.

Explore the Full Guide: Industrial Robot Knowledge Hub → Industrial Robot Fault Codes Library

Explore the complete guide for troubleshooting, repair strategies, and component replacement across industrial robot systems.

🔧 Recommended Parts for Fault Codes

Key components commonly involved in fault codes issues and replacements.