Fanuc 21 Alarms, Faults & Error Codes

Please contact us if you need information on FANUC 21 Alarms or testing, a repair or an exchange part. For further product information please visit our dedicated Fanuc 21 System & Parts Pages.

Program Errors/ Alarms on Program and Operation P/S Alarms

Alarm CodeType
000PLEASE TURN OFF POWER
001TH PARITY ALARM
002TV PARITY ALARM
003TOO MANY DIGITS
004ADDRESS NOT FOUND
005NO DATA AFTER ADDRESS
006ILLEGAL USE OF NEGATIVE SIGN
007ILLEGAL USE OF DECIMAL POINT
009ILLEGAL ADDRESS INPUT
010IMPROPER G–CODE
011NO FEEDRATE COMMANDED
014CAN NOT COMMAND G95 (M series)
014ILLEGAL LEAD COMMAND (T series)
015TOO MANY AXES COMMANDED (M series)
015TOO MANY AXES COMMANDED (T series)
020OVER TOLERANCE OF RADIUS
021ILLEGAL PLANE AXIS COMMANDED
022NO CIRCLE RADIUS
023ILLEGAL RADIUS COMMAND (T series)
025CANNOT COMMAND F0 IN G02/G03 (M series)
027NO AXES COMMANDED IN G43/G44 (M series)
028ILLEGAL PLANE SELECT
029ILLEGAL OFFSET VALUE (M series)
029ILLEGAL OFFSET VALUE (T series)
030ILLEGAL OFFSET NUMBER (M series)
030ILLEGAL OFFSET NUMBER (T series)
031ILLEGAL P COMMAND IN G10
032ILLEGAL OFFSET VALUE IN G10
033NO SOLUTION AT CRC (M series)
033NO SOLUTION AT CRC (T series)
034NO CIRC ALLOWED IN ST–UP /EXT BLK (M series)
034NO CIRC ALLOWED IN ST–UP /EXT BLK (T series)
035CAN NOT COMMANDED G31 (T series)
036CAN NOT COMMANDED G31 (M series)
037CAN NOT CHANGE PLANE IN CRC (M series)
037CAN NOT CHANGE PLANE IN NRC (T series)
038INTERFERENCE IN CIRCULAR BLOCK (M series)
038INTERFERENCE IN CIRCULAR BLOCK (T series)
039 CHF/CNR NOT ALLOWED IN NRC (T series)
040INTERFERENCE IN G90/G94 BLOCK (T series)
041INTERFERENCE IN CRC (M series)
041INTERFERENCE IN NRC (T series)
042G45/G48 NOT ALLOWED IN CRC (M series)
044G27–G30 NOT ALLOWED IN FIXED CYC (M series)
046ILLEGAL REFERENCE RETURN COMMAND
050CHF/CNR NOT ALLOWED IN THRD BLK (M series)
050CHF/CNR NOT ALLOWED IN THRD BLK(T series)
051MISSING MOVE AFTER CHF/CNR (M series)
 051MISSING MOVE AFTER CHF/CNR (T series)
 052CODE IS NOT G01 AFTER CHF/CNR (M series)
 052CODE IS NOT G01 AFTER CHF/CNR (T series)
 053TOO MANY ADDRESS COMMANDS (M series)
 053TOO MANY ADDRESS COMMANDS (T seires)
 054NO TAPER ALLOWED AFTER CHF/CNR (T series)
 055MISSING MOVE VALUE IN CHF/CNR (M series)
 055MISSING MOVE VALUE IN CHF/CNR (T series)
 056NO END POINT & ANGLE IN CHF/CNR (T series)
 057NO SOLUTION OF BLOCK END (T series)
 058END POINT NOT FOUND (M series)
 058END POINT NOT FOUND (T series)
 059PROGRAM NUMBER NOT FOUND
 60SEQUENCE NUMBER NOT FOUND
 61ADDRESS P/Q NOT FOUND IN G70–G73 (T series)
 62ILLEGAL COMMAND IN G71–G76 (T series)
 63SEQUENCE NUMBER NOT FOUND (T series)
 64SHAPE PROGRAM NOT MONOTONOUSLY (T series)
 65ILLEGAL COMMAND IN G71–G73 (T series)
 66IMPROPER G–CODE IN G71–G73 (T series)
 67CAN NOT ERROR IN MDI MODE (T series)
 69FORMAT ERROR IN G70–G73 (T series)
 70NO PROGRAM SPACE IN MEMORY
 71DATA NOT FOUND
 72TOO MANY PROGRAMS
 73PROGRAM NUMBER ALREADY IN
 74ILLEGAL PROGRAM NUMBER
 75PROTECT
 76ADDRESS P NOT DEFINED
 77SUB PROGRAM NESTING ERROR
 78NUMBER NOT FOUND
 79PROGRAM VERIFY ERROR
 80G37 ARRIVAL SIGNAL NOT ASSERTED (M series)
 80G37 ARRIVAL SIGNAL NOT ASSERTED (T series)
 81OFFSET NUMBER NOT FOUND IN G37 (M series)
 81OFFSET NUMBER NOT FOUND IN G37 (T series)
 82H–CODE NOT ALLOWED IN G37 (M series)
 82T–CODE NOT ALLOWED IN G37 (T series)
 83ILLEGAL AXIS COMMAND IN G37 (M series)
 83ILLEGAL AXIS COMMAND IN G37 (T series)
 85COMMUNICATION ERROR
 86DR SIGNAL OFF
 87BUFFER OVERFLOW
 90REFERENCE RETURN INCOMPLETE
 91 REFERENCE RETURN INCOMPLETE
 92 AXES NOT ON THE REFERENCE POINT
 94 P TYPE NOT ALLOWED (COORD CHG)
 95P TYPE NOT ALLOWED (EXT OFS CHG)
 96 P TYPE NOT ALLOWED (WRK OFS CHG)
 97 P TYPE NOT ALLOWED (AUTO EXEC)
 98 G28 FOUND IN SEQUENCE RETURN
 99MDI EXEC NOT ALLOWED AFT. SEARCH
 100 PARAMETER WRITE ENABLE
101PLEASE CLEAR MEMORY
110DATA OVERFLOW
111CALCULATED DATA OVERFLOW
112DIVIDED BY ZERO
113IMPROPER COMMAND
114FORMAT ERROR IN MACRO
115ILLEGAL VARIABLE NUMBER
116WRITE PROTECTED VARIABLE
118PARENTHESIS NESTING ERROR
119ILLEGAL ARGUMENT
122FOUR FOLD MACRO MODAL–CALL
123CAN NOT USE MACRO COMMAND IN DNC
124124 MISSING END STATEMENT
125125 FORMAT ERROR IN MACRO
126ILLEGAL LOOP NUMBER
127NC, MACRO STATEMENT IN SAME BLOCK
128ILLEGAL MACRO SEQUENCE NUMBER
129ILLEGAL ARGUMENT ADDRESS
130ILLEGAL AXIS OPERATION
131TOO MANY EXTERNAL ALARM MESSAGES
132132 ALARM NUMBER NOT FOUND
133ILLEGAL DATA IN EXT. ALARM MSG
135ILLEGAL ANGLE COMMAND (M series)
135135 SPINDLE ORIENTATION PLEASE (T series)
136ILLEGAL AXIS COMMAND (M series)
136C/H–CODE & MOVE CMD IN SAME BLK. (T series)
137M–CODE & MOVE CMD IN SAME BLK.
139CAN NOT CHANGE PMC CONTROL AXIS
141CAN NOT COMMAND G51 IN CRC (M series)
142ILLEGAL SCALE RATE (M series)
143SCALED MOTION DATA OVERFLOW (M series)
144ILLEGAL PLANE SELECTED (M series)
145ILLEGAL CONDITIONS IN POLAR COORDINATE INTERPOLATION
146IMPROPER G CODE
148ILLEGAL SETTING DATA (M series)
149FORMAT ERROR IN G10L3 (M series)
150ILLEGAL TOOL GROUP NUMBER
151TOOL GROUP NUMBER NOT FOUND
152NO SPACE FOR TOOL ENTRY
153T–CODE NOT FOUND
154NOT USING TOOL IN LIFE GROUP (M series)
155ILLEGAL T–CODE IN M06 (M series)
155ILLEGAL T–CODE IN M06 (T series
156P/L COMMAND NOT FOUND
157TOO MANY TOOL GROUPS
158ILLEGAL TOOL LIFE DATA
159TOOL DATA SETTING INCOMPLETE
175ILLEGAL G107 COMMAND
176IMPROPER G–CODE IN G107 (T series)
177CHECK SUM ERROR (G05 MODE)
178G05 COMMANDED IN G41/G42 MODE
179PARAM. (NO. 7510) SETTING ERROR
180COMMUNICATION ERROR (REMOTE BUF)
190ILLEGAL AXIS SELECT (M series)
194SPINDLE COMMAND IN SYNCHRO–MODE
195MODE CHANGE ERROR
197C–AXIS COMMANDED IN SPINDLE MODE
199MACRO WORD UNDEFINED
200ILLEGAL S CODE COMMAND
201FEEDRATE NOT FOUND IN RIGID TAP
2022 POSITION LSI OVERFLOW
203PROGRAM MISS AT RIGID TAPPING
204ILLEGAL AXIS OPERATION
205 RIGID MODE DI SIGNAL OFF
206CAN NOT CHANGE PLANE (RIGID TAP) (M series)
210CAN NOT COMMAND M198/M199
211G31 (HIGH) NOT ALLOWED IN G99
212ILLEGAL PLANE SELECT (M series)
212ILLEGAL PLANE SELECT (T series)
213ILLEGAL COMMAND IN SYNCHRO–MODE
214ILLEGAL COMMAND IN SYNCHRO–MODE
217DUPLICATE G51.2 (COMMANDS) (T series)
218NOT FOUND P/Q COMMAND IN G251 (T series)
219COMMAND G250/G251 INDEPENDENTLY (T series)
220ILLEGAL COMMAND IN SYNCHR–MODE (T series)
221ILLEGAL COMMAND IN SYNCHR–MODE (T series)
224RETURN TO REFERENCE POINT (M series)
224RETURN TO REFERENCE POINT (T series)
231ILLEGAL FORMAT IN G10 OR L50
233DEVICE BUSY
239BP/S ALARM
240BP/S ALARM
244P/S ALARM (T series)
245T–CODE NOT ALOWEE IN THIS BLOCK (T series)
253G05 IS NOT AVAILABLE (M series)
5010END OF RECORD
5014TRACE DATA NOT FOUND (M series)
5020PARAMETER OF RESTART ERROR
5030ILLEGAL COMMAND (G100) (T series)
5031ILLEGAL COMMAND (G100, G102, G103) (T series)
5032NEW PRG REGISTERED IN B–AXS MOVE (T series)
5033NO PROG SPACE IN MEMORY B–AXS (T series)
5034PLURAL COMMAND IN G110 (T series)
5035NO FEEDRATE COMMANDED B–AXS (T series)
5036ADDRESS R NOT DEFINED IN G81–G86 (T series)
5037ADDRESS Q NOT DEFINED IN G83 (T series)
5038TOO MANY START M–CODE COMMAND (T series)
5039START UNREGISTERED B–AXS PROG (T series)
5040CAN NOT COMMANDED B–AXS MOVE (T series)
5041CAN NOT COMMANDED G110 BLOCK (T series)
5044G68 FORMAT ERROR (M series)
5074ADDRESS DUPLICATION ERROR

 

Background Edit Alarms

Alarm CodeTypeDescription of Alarm/Error
???BP/S alarmBP/S alarm occurs in the same number as the P/S alarm that occurs in ordinary program edit ( 070, 071, 072, 073, 074, 085, 086, 087 etc)
140BP/S alarmIt was attempted to select or delete in the background a program being selected in the foreground. (Note)

Note: Alarm in background edit is displayed in the key input line of the background edit screen instead of the ordinary alarm screen and is resettable by any of the MDI key operation.

 

Absolute Pulse Code (APC) Alarms

Alarm CodeTypeDescription of Alarm/Error
300nth-axis origin returnManual reference position is required for the nth-axis.(n=1-8)
301APC alarm: nth axis communicationnth- axis communication error. (n=1-4)Failure in data transmission.
302APC alarm: nth axis over timenth- axis (n=1-4) APC overtime error.
303APC alarm: nth axis framingnth- axis (n=1-4) APC overtime error. Failure in data transmission.
304APC alarm: nth axis paritynth- axis (n=1-4) APC Paraity error. Failure in data transmission.
305APC alarm: nth axis pulse errornth- axis (n=1-4) APC pulse error alarm.
306APC alarm: ntha xis battery voltage 0nth- axis A(n=1-4) PC battery voltage has decreased to a low level so that data cannot be held.
307APC alarm: nth axis battery low 1nth- axis (n=1-4) axis APC battery voltage reached a level where the battery must be renewed
308APC alarm: nth axis battery low 2nth- axis (n=1-4) APC battery voltage reached a level where the battery must be renewed( including when power is OFF)
309APC ALARM: n AXIS ZRN IMPOSSIBLEAn attempt was made to perform reference position return without rotating the motor through one or more turns.

 

Serial Pulse Coder (SPC) Alarms

Alarm Code
TypeDescription of Alarm/Error
350SPC ALARM: n AXIS PULSE CODERThe n axis (axis 1-4) pulse coder has fault.
351SPC ALARM: n AXIS COMMUNICATIONn axis (axis 1-4) serial pulse coder communication error.

 

Servo Alarms

Alarm CodeTypeDescription of Alarm/Error
400SERVO ALARM: n-TH AXIS OVERLOADThe n-th axis ( axis 1-4) overload signal is on.
401SERVO ALARM:  n-TH AXIS VRDY OFFThe n-th axis ( axis 1-4) servo amplifier READY signal went off.
404SERVO ALARM: n-TH AXIS VRDY ONEven though the n-th axis ( axis 1-4) READY signal ( MCON) went off, the servo amplifier READY signal (DRDY) is still on. Or, when the power was turned on, DRDY went on even though MCON was off.
405SERVO ALARM: ZERO POINT RETURN FAULTPosition control system fault. Due to an NC or servo system fault in the reference position return, there is the possibility that the reference position return could not be executed correctly.
407SERVO ALARM:EXCESS ERRORThe difference in synchronous axis position deviation exceeded the set value.
409TORQUEALM: EXCESS ERRORAn abnormal load on the servo motor was detected. Alternatively an abnormal load on the spindle motor was detected in Cs mode.
410SERVO ALARM: n-th AXIS EXCESS ERRORThe position deviation value when  the  n-th axis (axis 1-4) stops is larger than the set value.
411SERVO ALARM: n-TH AXIS EXCESS ERRORThe position deviation value when  the  n-th axis (axis 1-4) moves is larger than the set value.
413SERVO ALARM: n-TH AXIS- LSI OVERFLOWThe contents of the error register for the n-th axis (axis 1-4) are beyond the range of    to    . This error usually occurs as the result of improperly set parameters.
414SERVO ALARM: n-TH AXIS -DETECTION RELATED ERRORN-th axis (axis 1-4_ digital servo system fault.
415SERVO ALARM: n-TH AXIS-EXCESS SHIFTA speed higher than 511875 unit/s was attempted to be set in the n-th axis ( axis 1-4). This error occurs as the result of improperly set CMR.
416SERVO ALARM: n-TH AXIS-DISCONNECTIONPosition detection system fault in the n-th axis ( axis 1-4) pulse coder ( disconnection alarm).
417SERVO ALARM: n-TH AXIS-PARAMETER INCORRECTThis alarm occurs when the n-th axis ( axis 1-4) is in one of the conditions below: ( Digital servo system alarm)

  1. The value set in Parameter no 20200 (motor form) is out of the specified limit.
  2.  A proper value ( 111 or -111) is not set in parameter no 2022.( motor revolution direction).
  3. Illegal data ( a value below 0, etc) was set in parameter No 2023 ( number of speed feedback pulses per motor revolution)
  4. Illegal data ( a value below 0, etc) was set in parameter No 2024 ( number of speed feedback pulses per motor revolution)
  5. Parameters No. 2084 and No. 2085 (flexible field gear rate) have not been set.
  6. A value outside the limit of {1 to the number of control axes) or a non continuous value ( parameter 1023( servo axis number) contains a value out of the range from 1 to the number or axes, or an isolated value ( for example 4, not preceeded by 3). was set in parameter No. 1023 ( servo axis number)
420SYNC TORQUE@ EXCESS ERRORWhen simple synchronous control is applied, the torque command difference between the master and slave axes exceeded the value set in parameter No. 2031.
421EXCESS ER(D)’: EXCESS ERRORWhen the dual position feedback function is being applied, an excessive difference was detected between a semi-closed lopp and closed loop error.
422EXCESS ER(D)’: SPEED ERROR The specified allowable speed has been exceeded while torque control for the PMC axis control is applied.
423EXCESS ER(D)’: EXCESS ERROR The allowable total amount of travel, set in a parameter has been exceeded while torque control for the PMC axis control is applied.

Overtravel Alarms

Alarm CodeTypeDescription of Alarm/Error
500 OVER TRAVEL: +n Exceeded the n-th axis + side stored stroke limit I.

(Parameter NO 1320 or 1326)

501 OVER TRAVEL: -n Exceeded the n-th axis _ side stored stroke limit I.

(Parameter NO 1321 or 1327)

502 OVER TRAVEL: +n Exceeded the n-th axis + side stored stroke limit II.

(Parameter NO 1322)

503 OVER TRAVEL:  -n Exceeded the n-th axis _ side stored stroke limit II.

(Parameter NO 1323)

504 OVER TRAVEL: +n Exceeded the n-th axis + side stored stroke limit III.

(Parameter NO 1324)

505 OVER TRAVEL: -n Exceeded the n-th axis _ side stored stroke limit III.

(Parameter NO 1325)

506 OVER TRAVEL: +n Exceeded the n-th axis + side hardware OT
507 OVER TRAVEL: -n Exceeded the n-th axis _ side hardware OT

Overheat Alarms

Alarm CodeTypeDescription of Alarm/Error
700OVERHEAT: CONTROL UNITControl unit overheat
701OVERHEAT: FAN MOTORThe fan motor on top of the cabinet for the control unit is overheated
704OVERHEAT: SPINDLESpindle overheat in the spindle fluctuation detection.

 

Rigid Tapping Alarms

Alarm CodeTypeDescription of Alarm/Error
740RIGID TAP ALARM: EXCESS ERRORThe positional deviation of the stopped spindle has exceeded the set value during rigid tapping.
741RIGID TAP ALARM: EXCESS ERRORThe positional deviation of the moving spindle has exceeded the set value during rigid tapping.
742RIGID TAP ALARM: LSI OVERFLOWAn LSI overflow has occurred for the spindle during rigid tapping.

 

Serial Spindle Alarms

Alarm CodeTypeDescription of Alarm/Error
749 S SPINDLE LSI ERROR It is serial communication error while system is executing after power supply on.
750 SPINDLE SERIAL LINK START FAULT This alarm is generated when the spindle control unit is not ready for starting correctly when the power is turned on in the system with the serial spindle.
751FIRST SPINDLE ALARM DETECTION ( AL-XX) This alarm indicates in the NC that an alarm is generated in the spindle unit of the system with serial spindle.
752FIRST SPINDLE MODE CHANGE FAULT This alarm is generated if the system does not properly terminate a mode change.
754SPINDLE 1 ABNORMAL TORQUE ALARM Abnormal first spindle motor load has been detected.
761SECOND SPINDLE ALARM DETECTION (AL-XX) Refer to alarm No 751 for 2nd axis.
762 SECOND SPINDLE MODE CHANGE FAULT Refer to alarm No 752 for 2nd axis.
764SPINDLE 2 ABNORMAL TORQUE ALARM Refer to alarm No 754 for 2nd spindle

 

System Alarms

Alarm CodeTypeDescription of Alarm/Error
900ROM PARITY F-ROM parity error in a ROM file ( control software), such as CNC macro, or digital servo. The F-ROM module may be defective.
910DRAM PARITY: (Low)For an SRAM parity error, initialise the memory. If the error subsequently recurs, or in the case  of a DRAM parity error, replace RAM module. Subsequently set the parameters and all other data again.
911DRAM PARITY: (High)For an SRAM parity error, initialise the memory. If the error subsequently recurs, or in the case  of a DRAM parity error, replace RAM module. Subsequently set the parameters and all other data again.
912SRAM PARITY: (Low)For an SRAM parity error, initialise the memory. If the error subsequently recurs, or in the case  of a DRAM parity error, replace RAM module. Subsequently set the parameters and all other data again.
913SRAM PARITY: (High)For an SRAM parity error, initialise the memory. If the error subsequently recurs, or in the case  of a DRAM parity error, replace RAM module. Subsequently set the parameters and all other data again.
920SERVO ALARM (1/2 AXIS)Servo alarm (1st or 2nd axis). A watchdog alarm or a RAM parity error in the servo module occured.
921SERVO ALARM (3/4 AXIS)Servo alarm (3rd or 4th axis). A watchdog alarm or a RAM parity error in the servo module occured.
924SERVO MODULE SETTING SERRORThe digital servo module is not installed. Check that the servo control module or servo interface module on the main board is mounted securely.
930CPU INTERRUPTCPU Error ( abnormal interrupt). The main board is faulty.
940PCB ERRORPCB ID error. The main board or the memory module may be defective.
950PMC SYSYTEM ALARMFault occured in the PMC. The PMC control module on the main board or the RAM module may be defective.
971NMI OCCURED IN SLCAn alarm condition occured in the interface with an I/O unit. Check the connection between the PMC control module on the main board and the I/O unit. Also, check that the power of the I/O unit is on and that the interface module is operating normally.
972NMI OCCURED IN OTHER MODULENMI occured in a board other than the main board. The main board or the back panel may be defective.
973NON MASK INTERRUPTNMI occured for an unknown reason. The printed board of the power unit or the main board may be defctive. Or there my be noise interference.
974BUS ERRORBus error. The main board may be defective