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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 Common Over Travel Alarm List (OT0500–OT0515)
During machine operation, if the motion exceeds the travel limits set in the FANUC system, an Over Travel Alarm will be triggered.These alarms serve to protect the machine from mechanical damage due to excessive travel or axis interference.This article summarizes the common Over Travel alarms (No. 500–515) and their troubleshooting methods. Common Overtravel Alarm Classification Below are the common FANUC Over Travel alarm codes and their meanings. Alarm No. Content Description 500 OVER TRAVEL : +n Exceeded the n–th axis + side stored stroke check I. (Parameter No.1320 or 1326) 501... Read more...
Common FANUC CNC Alarms Classification
During CNC machine operation, alarms may occasionally occur. To address these issues effectively, targeted troubleshooting and maintenance are required. This article provides a classification of common FANUC system alarms for reference, helping technicians respond correctly when problems arise. FANUC Alarm Classification FANUC system alarms refer to faults detected in CNC hardware or software. Alarms are classified according to their numbers as follows: Alarm Number Range Category 000~ Programming & Operation 300~ Pulse Encoder 400~ Servo 500~ Overtravel 700~ Overheat / Temperature Exception 749~ Spindle Communication 900~ CNC System 5000~ Programming... Read more...
Fanuc Common Servo Alarm & How to Troubleshoot | REACO CNC
How to solve Fanuc common servo alarm? The following table lists frequently encountered Fanuc alarm codes with their typical causes and suggested troubleshooting steps. Group  Servo Alarms: SV0401~SV0411  Servo Alarms: SV0413~SV0423 Servo Alarms: SV0430~SV0439 Servo Alarms: SV0440~SV0449 Servo Alarms: SV0460~SV0468 Servo Alarms: SV0600~SV0607 Servo Alarms: SV0608~SV0613 Related Servo Cases Other Articles Related Articles Here are some related technical resources you may also find helpful: Common FANUC CNC Alarms Classification FANUC Common Over Travel Alarm List FANUC G/ M Code for a Machining Center FANUC G/ M Code for lathe How... Read more...

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