Fanuc Alarm Code
Fanuc alarms are essentially the FANUC CNC producing errors due to hardware, software faults or the execution of programs. There are many different alarms produced on the many series of Fanuc controls from the late 1970’s to current drives and controls.
System ALM errors
Drive Faults for Servo, Spindle and PSM
Pulse coder (Absolute APC) & (Serial SPC) codes
Overtravel ALM (OT)
Program errors (P/S alarm)
Being involved with Fanuc for decades we have always thought better to list SYSTEMS, drives, comms, and functinonal errors seperately.

Fanuc drives, systems alarm using lit LED’s or alphanumeric characters.
Below is a fanuc error codes list by drives and system. If anything is missing please contact us for more information.
Fanuc Drives & ALPHA module alarms:
- FANUC ALPHA spindle module & aiSP
- Special mention: Spindle Amplifier: 12
- Special mention: Spindle Amplifier: 31
- FANUC ALPHA Servo module & aiSV
- Special mention: Servo amplifier: 8/9/A
- FANUC ALPHA Power supply & aiPS codes
- Special mention: Power Module: 01
- FANUC BETA faults (only servo)
- FANUC BETA biSVSP error codes
- Special mention: biSVSP AL. 04 & 51
- Special mention: biSVSP AL. 20
- Fanuc DC Axis faults
- Fanuc AC Axis faults (6050) / AC Servo alarms (6058, 6066)
- Fanuc AC spindle drive fault codes (S / P / I Series)
- Fanuc AC servo amplifier units
- Special mention: C Series Amplifier: 02
Fanuc System alarms:
- Fanuc 0, 0M, 0T codes.
- 930 CPU alarm
- Fanuc 6, 6M, 6T errors
- Fanuc 10 & 11 ALM – 10 & 11 master pcb error codes
- Fanuc 15 codes
- Fanuc 16 / 18 / 21 system codes.
- Fanuc 16i / 18i / 21i error code.
- 368/369 Error (FSSB communication)
- 351 Alarms (feedback)
P/S Faults / Program Errors (common)
- PS84 & PS85
- PS101
Error codes and alarms produced on Fanuc amplifiers, system, power supply units and modules, I/O racks operating the PLC side of the CNC are extensive. They do take time to understand and unfortunately our lists will never negate the need for a quality CNC maintanence engineer to visit site and diagnose and solve faults on your machine(s).
For more details on Fanuc faults our world agent has written extensive Fanuc error/ALM/code/fault info for nearly all systems, drives and everything else in the Fanuc CNC feedback loop.