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FANUC Alarm Code Guide

Find solutions to common Fanuc CNC alarm codes quickly and efficiently.

Servo Alarm
Spindle Alarm
System Alarm
Overtravel Alarm

FANUC Alarms: Quick Guide to Get Back Online​

When your FANUC CNC triggers an alarm, it's trying to tell you something. From simple overtravel to complex servo issues, these codes pinpoint where the problem lies.Our guide cuts through the complexity. We explain the most common alarms—what they mean, why they happen, and how to fix them. Whether you're facing alarm 401 or a stuck overtravel limit, you'll find clear, step-by-step solutions to minimize downtime.​​ You will learn how to:​​

  • Decode any FANUC alarm number.
  • Diagnose faults in servos, spindles, or system memory.
  • Perform basic checks before calling a technician.
  • Identify components that may need adjustment or replacement.

Get the knowledge to solve problems faster and keep your machines running.
FANUC CNC Alarm Codes (1001 and Above)
This page covers FANUC CNC alarm codes 1001 and above for: FANUC Series 0i-Model D FANUC Series 0i Mate-Model D These alarm references may appear as: PS alarms – Program-related alarms BG alarms – Background editing alarms SR alarms – Communication alarms Important: PS, BG, and SR alarms use the same shared numeric alarm code system.The alarm number alone does not identify the alarm type. The actual prefix is displayed only on the CNC system screen, such as PS1001, BG1095, or SR2032. This page is useful for: CNC operators Maintenance... Read more...
FANUC CNC Alarm Codes (0401–1000)
This page continues the FANUC alarm reference for alarm numbers 0401–1000. These alarm references apply to: FANUC Series 0i-Model D FANUC Series 0i Mate-Model D The alarms in this section may appear as: PS alarms – Program-related alarms BG alarms – Background editing alarms SR alarms – Communication alarms Important: PS, BG, and SR alarms share the same numeric alarm code system.The number alone does not identify the alarm type. The actual prefix is shown only on the CNC screen, such as PS0412, BG0518, or SR0601. This page is useful... Read more...
FANUC CNC Alarm Codes (0201–0400)
This page continues the FANUC alarm reference for alarm numbers 0201–0400. These alarm references apply to: FANUC Series 0i-Model D FANUC Series 0i Mate-Model D The alarms in this section may appear as: PS alarms – Program-related alarms BG alarms – Background editing alarms SR alarms – Communication alarms Important: PS, BG, and SR alarms share the same numeric alarm codes.That means the number alone does not identify the alarm type. The actual prefix is displayed only on the CNC screen, such as PS0201, BG0233, or SR0085. This page is... Read more...
FANUC CNC Alarm Codes List (0001–0200)
FANUC CNC Alarm Codes (0001–0200) FANUC CNC alarm codes from 0001 to 0200 are some of the most frequently searched and most commonly encountered alarms in daily CNC programming, editing, and machine operation. This page covers alarm numbers that may appear as: PS alarms – Program-related alarms BG alarms – Background editing alarms SR alarms – Communication alarms These alarm references apply to: FANUC Series 0i-Model D FANUC Series 0i Mate-Model D This reference page is designed for: CNC machine operators Maintenance engineers FANUC service technicians CNC programmers Spare parts... Read more...
FANUC CNC Alarm Codes (PS / BG / SR Alarms)
What are PS, BG, and SR alarms? FANUC CNC alarms are displayed with prefixes such as: PS – Program-related alarms BG – Background editing alarms SR – Communication alarms Examples: PS0003 BG0085 SR0001 Browse FANUC Alarm Codes by Range FANUC Alarm Codes 0001–0200 FANUC Alarm Codes 0201–0400 FANUC Alarm Codes 0401–1000 FANUC Alarm Codes 1001+ Common FANUC Alarm Searches Users often search for: FANUC alarm code list FANUC PS alarm list FANUC CNC error codes FANUC alarm meanings FANUC troubleshooting guide About REACO CNC REACO CNC has over 33 years... Read more...
Complete FANUC Spindle Alarm Codes (SP9110–SP9216)
This page provides the complete FANUC serial spindle alarm list (final section), covering alarm codes from SP9110 to SP9216. These alarms mainly relate to: Power supply (PS) faults Communication errors Safety system issues Hardware failures and protection functions This section is essential for advanced troubleshooting and maintenance of FANUC CNC systems. FANUC Spindle Alarm List (SP9110–SP9216) 1) SP9110 – SP9113 Alarm Code Message Amplifier Display Cause Troubleshooting SP9110 Amplifier Communication Error B0 Communication failure between spindle amplifier and power supply Replace communication cable or unit SP9111 Inverter Control Voltage Low... Read more...
FANUC Spindle Alarm Codes (SP9034–SP9092)
This page continues the FANUC serial spindle alarm list, covering alarm codes from SP9034 to SP9092. These alarms mainly involve: Parameter errors Encoder and sensor faults Spindle synchronization issues Communication and hardware failures Understanding these alarms helps reduce downtime and improve CNC machine reliability. FANUC Spindle Alarm List (SP9034–SP9092) 1) SP9034 – SP9043 Alarm Code Message Amplifier Display Cause Troubleshooting SP9034 SSPA:34 Parameter Illegal 34 Parameter value exceeds allowable range Refer to parameter manual and correct values SP9036 SSPA:36 Error Counter Overflow 36 Position error counter overflow Reduce position gain... Read more...
FANUC Serial Spindle Alarm Codes (SP9001–SP9033)
When a serial spindle alarm occurs in a FANUC CNC system, the CNC displays an alarm number for diagnosis. If the red LED on the spindle amplifier lights up, a two-digit alarm code is shown. ⚠️ Important Notes: A yellow LED indicates a sequence-related issue, not a hardware fault Example: spindle rotation command issued while emergency stop is active Alarm meanings differ depending on LED status For alarm codes not listed here, refer to: FANUC AC Spindle Motor αi Series Maintenance Manual (B-65285EN) FANUC Spindle Alarm List (SP9001–SP9033) 1) SP9001 –... Read more...
FANUC Serial Spindle Error Codes List (01–44) – Causes & Solutions
REACO CNC is a global supplier of FANUC CNC parts, spindle amplifiers, and Mitsubishi automation components. With over 34 years of experience, we provide reliable products, professional repair services, and worldwide shipping support. This article provides a complete list of FANUC serial spindle amplifier error codes (01–44), including detailed causes and troubleshooting solutions to help engineers and maintenance personnel quickly diagnose spindle issues.  Important Notes When the yellow LED indicator on the spindle amplifier is ON, a two-digit error code is displayed. When the red LED indicator is ON, it... Read more...
FANUC CNC Troubleshooting Guide (Part 5): EX107, DC LINK & 4th Axis Setup
FANUC CNC systems are widely used in industrial automation, but users may encounter various alarms and configuration issues during operation. In this guide, we cover common FANUC CNC problems such as EX107 alarm, DC LINK voltage issues, and 4th axis configuration, along with practical solutions. With over 30 years of experience, REACO CNC provides professional support, spare parts, and repair services for FANUC CNC systems worldwide. Frequently Asked Questions (FAQ) 1. What parameters need to be modified when adding a 4th axis to FANUC 0i-MF? When adding a 4th axis, the... Read more...
FANUC CNC Troubleshooting Guide (Part 4): System Settings, Communication, and Maintenance
In addition to alarms, FANUC CNC systems may encounter issues related to system configuration, communication protocols, maintenance, and parameter settings. Proper handling of these situations is essential to ensure machine safety and performance. This guide covers practical troubleshooting topics including power modules, IO errors, PROFINET communication, and system operation precautions. 1. Where to Get FANUC Power Module Manuals? Answer To obtain detailed information about FANUC power modules, including: Alarm descriptions Wiring diagrams Dimensions Technical specifications You can refer to: Servo amplifier specification manuals System hardware connection manuals Maintenance manuals 2.... Read more...
FANUC CNC Alarm Troubleshooting Guide (Part 3): System Errors and Advanced Diagnostics
FANUC CNC systems may occasionally encounter complex alarms related to system memory, communication, servo feedback, or configuration errors. These issues often require deeper diagnostics and proper understanding of system architecture. This guide covers advanced FANUC CNC alarms and troubleshooting methods to help engineers and operators quickly identify and resolve problems. 1. How to Fix FANUC ROM Parity Error (NC Basic)? Cause ROM parity error (NC Basic) usually indicates a FROM memory failure, which may be caused by: Hardware issues Corrupted system software Solution Contact FANUC technical support Or consult REACO... Read more...

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