FANUC P/S Alarm Codes: Common Programming Alarms on CNC Lathes and Machining Centers

30 July 2026

Mentor CNC Editör Ekibi

The P/S (Program / Syntax) alarms that appear on FANUC control screens are most often caused by a typo in the program, a missing address, or a command sequence the control did not expect. This page collects the P/S alarm codes that are not yet covered on Mentor CNC’s other pages (the FANUC 0/00/0-Mate guide, the G71/G72/G74/G75 cycle pages, and CNC Milling Lesson 9).

⚠️ Series notice: The same alarm number can behave slightly differently across FANUC series (0i, 16i/18i/21i, 30i/31i/32i, etc.); some alarms may not exist at all on some series. The explanations below reflect general FANUC P/S alarm logic. Before applying anything on your own machine, always verify the exact alarm number and message shown on your control’s screen against your machine’s own operator/alarm manual.

General Programming and Syntax Errors

P/S 001 — ADDRESS NOT FOUND

Machine type: Lathe and machining center (general programming error)
Meaning: No numeric value was entered after an address (e.g. X, Y, Z); another address or end of block followed instead.
Example of incorrect use: `X Y100` (no value after X)

Solution: Always write a valid number after every address. Example: `X100 Y100`

P/S 003 — TH PARITY ALARM (Tezgâh Tipi: Özellikle veri aktarımı yapılan tüm tezgâhlar)

Machine type: Lathe and machining center — usually occurs when reading a program via RS232 or a memory card.
Meaning: A bit with incorrect parity was detected during reading. There may be noise or a cable problem on the data communication line.

Solution:

  • Check the data transfer cables and connections.
  • Verify the I/O parameters (stop bit, baud rate) against the machine manual.
  • Reload the program. If the problem persists, the computer or the card interface may be faulty.

P/S 004 — TV PARITY ALARM

Machine type: Lathe and machining center (when TV control is active)
Meaning: The number of characters in a block was odd, triggering a TV (vertical) parity check error. This alarm only occurs when TV parity check is enabled.

Solution:

  • You can disable TV control via a parameter.
  • Or add a space to the block to make the character count even.

P/S 005 — TOO MANY DIGITS

Machine type: Lathe and machining center
Meaning: More digits were entered for an address than the maximum allowed. (e.g. X1234567890)

Solution: Make sure the value is within the valid range (generally no more than 8 digits).

P/S 006 — ILLEGAL USE OF NEGATIVE SIGN

Machine type: Lathe and machining center
Meaning: The "-" sign was used incorrectly — a second "-" after an address, or a "-" without an address.
Example of incorrect use: `X- -100`

Solution: Use only one "-" sign per address, and make sure it comes before the number.

P/S 007 — ILLEGAL USE OF DECIMAL POINT

Machine type: Lathe and machining center
Meaning: A decimal point (".") was used where it should not be (e.g. immediately after an address).

Solution: Use the decimal point only within a numeric value, not right after the address.

P/S 008 — PROGRAM HAS AN ERROR AT THE END

Machine type: Lathe and machining center
Meaning: The program was not terminated with `M02`, `M30` or `M99`; only a `%` was used to end it.

Solution: Add the correct end code to the end of the program: `M30` for the main program, `M99` for a subprogram.

P/S 009 — ILLEGAL ADRESS INPUT

Machine type: Lathe and machining center
Meaning: An invalid character (address) was used — for example `@` or `#`.

Solution: Use only valid addresses (X, Y, Z, G, M, F, S, T, etc.).

P/S 011 — NO FEEDRATE COMMANDED

Machine type: Lathe and machining center
Meaning: No F (feedrate) value was entered in a cutting move block.

Solution: Always define an F value in every `G01`, `G02`, `G03`, etc. block.

P/S 014 — ILLEGAL LEAD COMMAND

Machine type: Lathe (variable-lead threading)
Meaning: In a variable-lead thread (G34) command, the lead increase/decrease given by the K address exceeded the maximum value or was negative.

Solution: Check the K value; make sure it is positive and within the allowed limits.

P/S 015 — TOO MANY AXES COMMANDED

Machine type: Machining center (multi-axis)
Meaning: More axes were commanded than can be controlled simultaneously.

Solution: Do not specify more axes than necessary in the same block; check the machine's axis capacity.

Circular Interpolation and Plane Selection Errors

P/S 020 — OVER TOLERANCE OF RADIUS

Machine type: Lathe and machining center (circular interpolation)
Meaning: While drawing an arc with `G02/G03`, the difference between the distance from the start point to the arc center and the distance to the end point exceeded the tolerance set in parameter 0876.

Solution: Check the start, end and center coordinates in the program, or increase the 0876 tolerance (with caution).

P/S 021 — ILLEGAL PLANE AXIS COMMANDED

Machine type: Lathe and machining center
Meaning: During circular interpolation, an axis not belonging to the selected plane (G17/G18/G19) was commanded.

Solution: Make sure the correct plane is selected before a circular move.

P/S 023 — ILLEGAL RADIUS COMMAND

Machine type: Lathe and machining center
Meaning: A negative radius value was entered while drawing an arc with R.

Solution: The R value must be positive.

P/S 028 — ILLEGAL PLANE SELECT

Machine type: Lathe and machining center
Meaning: Two or more axes were incorrectly specified at the same time during plane selection (G17/G18/G19).

Solution: Check the correct plane selection.

Tool Offset and Tool Radius Compensation (CRC) Errors

P/S 029 — ILLEGAL OFFSET VALUE

Machine type: Lathe and machining center (tool offset)
Meaning: The offset value specified with a T code is too large.

Solution: Check the offset values and make sure they are within the valid range.

P/S 030 — ILLEGAL OFFSET NUMBER

Machine type: Lathe and machining center
Meaning: The offset number specified in the T function is outside the valid range.

Solution: Check the T number (e.g. T0101, offset 01).

P/S 031 — ILLEGAL P COMMAND IN G10

Machine type: Lathe and machining center
Meaning: While setting an offset with `G10`, the offset number following the P address is invalid or too large.

Solution: Check the P value.

P/S 032 — ILLEGAL OFFSET VALUE IN G10

Machine type: Lathe and machining center
Meaning: While writing an offset with `G10` or system variables, the amount is too large.

Solution: Enter the offset amount within the limits.

P/S 033 — NO SOLUTION AT CRC

Machine type: Lathe and machining center (tool nose radius compensation)
Meaning: During tool nose radius compensation (G41/G42), the intersection point could not be calculated.

Solution: Review the move geometry in the program; there may be insufficient clearance or corners that are too tight.

P/S 034 — NO CIRC ALLOWED IN ST-UP/EXT BLK

Machine type: Lathe and machining center
Meaning: In tool radius compensation mode, a `G02/G03` circular move cannot be used in the start-up or cancel block.

Solution: Use a linear (G01) move before or after G41/G42.

P/S 035 — CAN NOT COMMANDED G31

Machine type: Lathe and machining center
Meaning: G31 (skip cutting) was commanded while in tool radius compensation mode.

Solution: Do not use G31 while G41/G42 is active.

P/S 036 — INTERFERENCE IN CIRCULAR BLOCK

Machine type: Lathe and machining center
Meaning: During tool radius compensation, an arc block would cause excessive cutting — there is interference with the arc center.

Solution: Recalculate the arc coordinates in the program.

P/S 037 — CAN NOT CHANGE PLANE IN CRC

Machine type: Lathe and machining center
Meaning: The plane cannot be changed while tool radius compensation is active.

Solution: Cancel compensation with G40 before changing the plane.

P/S 039 — CHC/CNR NOT ALLOWED IN CRC

Machine type: Lathe and machining center
Meaning: Chamfering or corner-R (C/R) cannot be used in the compensation start-up/cancel block. It can cause excessive cutting.

Solution: Perform the chamfer before or after the compensation mode, not inside it.

P/S 040 — INTERFERENCE IN G90/G94 BLOCK

Machine type: Lathe (canned cycles)
Meaning: In G90/G94 canned cycles, tool radius compensation would cause excessive cutting.

Solution: Turn off compensation with G40 before the cycle, or adjust the program coordinates.

P/S 041 — INTERFERENCE IN CRC

Machine type: Lathe and machining center
Meaning: A general excessive-cutting condition in tool radius compensation.

Solution: Check the program geometry and the tool offset.

Reference Point Return Errors

P/S 046 — ILLEGAL REFERENCE RETURN COMMAND

Machine type: Lathe and machining center
Meaning: With `G28`, a P value other than P2, P3 or P4 was entered for returning to the 2nd, 3rd or 4th reference point.

Solution: Use only P2/P3/P4, or write G28 without a P.

P/S 090 — REFERENCE RETURN INCOMPLETE

Machine type: Lathe and machining center
Meaning: The return to reference point could not be completed — the starting point is too close to the reference, or the speed is too low.

Solution: Move the axis away from the reference point and perform the return at an adequate (rapid) speed.

P/S 091 — MANUAL RETURN TO REFERENCE POSITION IS IMPOSSIBLE

Machine type: Lathe and machining center
Meaning: Manual return to reference cannot be performed because the system is temporarily in a stop state.

Solution: Press RESET, then manually go to the reference point.

P/S 092 — AXES NOT ON THE REFERENCE

Machine type: Lathe and machining center
Meaning: The axis specified by a G28 (automatic reference return) or G27 (reference check) command did not reach the reference position.

Solution: Manually move the axis to the reference position and try again.

Chamfer, Corner-R and Direct Dimension Programming Errors

P/S 050 — CHF/CNR NOT ALLOWED IN THRD BLK

Machine type: Lathe (threading)
Meaning: A chamfer (C) or corner-R command was entered in a threading block.

Solution: Do not add these commands to a threading block.

P/S 051 — MISSING MOVE AFTER CHF/CNR

Machine type: Lathe and machining center
Meaning: The block following a chamfer or corner-R block has insufficient or unsuitable movement.

Solution: Add at least one linear move block after the chamfer.

P/S 052 — CODE IS NOT G01 AFTER CHF/CNR

Machine type: Lathe and machining center
Meaning: The block immediately following a chamfer or corner-R block is not linear (G01).

Solution: The move after a chamfer must be G01.

P/S 053 — TOO MANY ADDRESS COMMAND

Machine type: Lathe and machining center
Meaning: Two or more of I, K, R were specified in a chamfer block, or in direct dimension programming a character other than C/R follows the comma.

Solution: Use only the required address.

P/S 054 — NO TAPER ALLOWED AFTER CHF/CNR

Machine type: Lathe
Meaning: A chamfer or corner-R block contains a taper command.

Solution: Do not use a taper in a chamfer block.

P/S 055 — MISSING MOVE VALUE IN CHF/CNR

Machine type: Lathe and machining center
Meaning: The chamfer or corner-R amount is larger than the move distance in the block.

Solution: Increase the move distance or reduce the chamfer amount.

P/S 056 — NO END POINT & ANGLE IN CHF/CNR

Machine type: Lathe and machining center
Meaning: Only an angle (A) was specified in a chamfer block; the end point is missing.

Solution: Also enter an X or Z value.

P/S 057 — NO SOLUTION OF BLOCK END

Machine type: Lathe (direct drawing dimension programming)
Meaning: The block end could not be calculated in direct drawing programming.

Solution: Check the given angle and distance combination.

P/S 058 — END POINT NOT FOUND

Machine type: Lathe (direct drawing dimension programming)
Meaning: The block end point could not be found.

Solution: Review the coordinate and angle values again.

Program Number, Sequence Number and Memory Management Errors

P/S 059 — PROGRAM NUMBER NOT FOUND

Machine type: Lathe and machining center
Meaning: While searching for an external program number, the specified program could not be found in memory.

Solution: Verify the program number and make sure the program is loaded.

P/S 060 — SEQUENCE NUMBER NOT FOUND

Machine type: Lathe and machining center
Meaning: The N number specified in a sequence number search could not be found.

Solution: Check the N number.

P/S 063 — SEQUENCE NUMBER NOT FOUND

Machine type: Lathe (G70-G73)
Meaning: The sequence number specified in the P address could not be found.

Solution: Make sure the N number given with P exists in the program.

P/S 070 — NO PROGRAM SPACE IN MEMORY

Machine type: Lathe and machining center
Meaning: There is not enough space in memory.

Solution: Delete unneeded programs or work via DNC.

P/S 071 — DATA NOT FOUND

Machine type: Lathe and machining center
Meaning: The searched-for address or program number could not be found.

Solution: Check the value you entered.

P/S 072 — TOO MANY PROGRAMS

Machine type: Lathe and machining center
Meaning: The number of programs in memory exceeded the maximum limit (standard 63, option 125/200).

Solution: Delete unneeded programs.

P/S 073 — PROGRAM NUMBER ALREADY IN USE

Machine type: Lathe and machining center
Meaning: The program number you entered already belongs to another program.

Solution: Use a different number, or delete the old program.

P/S 074 — PROGRAM NUMBER

Machine type: Lathe and machining center
Meaning: The program number is outside the 1-9999 range.

Solution: Enter a valid number.

P/S 076 — ADDRESS P NOT DEFINED

Machine type: Lathe and machining center
Meaning: The P address is missing in a subprogram call with M98, G65 or G66.

Solution: Specify the program number to be called with P.

P/S 077 — SUB PROGRAM NESTING ERROR

Machine type: Lathe and machining center
Meaning: The subprogram nesting limit was exceeded (usually 8 levels).

Solution: Reduce the number of nested subprograms.

P/S 078 — NUMBER NOT FOUND

Machine type: Lathe and machining center
Meaning: The program/sequence number specified with M98/M99/G65/G66 or GOTO could not be found.

Solution: Check the target number and make sure the program has not been edited.

P/S 079 — PROGRAM VERIFY ERROR

Machine type: Lathe and machining center
Meaning: The program in memory does not match the program read from the external device.

Solution: Check both the program in memory and the source program, then reload.

Automatic Tool Offset Measurement (G37) Errors

P/S 080 — G37 ARRIVAL SIGNAL NOT ASSERTED

Machine type: Lathe and machining center (automatic tool measurement)
Meaning: During G37 (automatic tool compensation), no signal arrived within the specified area.

Solution: Check the tool measurement probe and the parameter settings.

P/S 081 — OFFSET NUMBER NOT FOUND IN G37

Machine type: Lathe and machining center
Meaning: No T code was specified while performing automatic compensation with G36/G37.

Solution: Give the T code in the same block or before it.

P/S 082 — T-CODE NOT ALLOWED IN G37

Machine type: Lathe and machining center
Meaning: A T code cannot be used in the same block as G36/G37.

Solution: Write the T code in a separate block.

P/S 083 — AXIS COMMAND IN G37

Machine type: Lathe and machining center
Meaning: The G36/G37 block contains an invalid axis command, or an incremental command was used.

Solution: Use absolute (G90) coordinates and specify valid axes.

Data Communication and DNC Errors

P/S 085 — COMMUNICATION ERROR

Machine type: Lathe and machining center (RS232 transfer)
Meaning: An overrun, parity or framing error occurred during data input via the reader/punch interface.

Solution: Check the cable, baud rate and stop bit settings.

P/S 086 — DR SIGNAL OFF

Machine type: Lathe and machining center
Meaning: The I/O device's ready (DR) signal turned off during data transfer.

Solution: Check the device's power, the cable and the PCB.

P/S 087 — BUFFER OVERFLOW

Machine type: Lathe and machining center
Meaning: A buffer overflow occurred during data transfer — 10 characters were read despite the end-of-read command.

Solution: The I/O device or PCB may be faulty; call for service.

P/S 180 — COMMUNICATION ERROR (REMOTE BUF)

Machine type: Lathe and machining center
Meaning: A remote buffer connection error.

Solution: Check the cable, parameters and I/O unit.

Coordinate System and P-Type Command Errors

P/S 094 — P TYPE NOT ALLOWED (COORD CHG)

Machine type: Lathe and machining center (program restart)
Meaning: A P type cannot be specified during program restart after a coordinate system change.

Solution: Follow the correct restart procedure.

P/S 095 — P TYPE NOT ALLOWED (EXT OFS CHG)

Machine type: Lathe and machining center
Meaning: A P type cannot be used during program restart if the external workpiece offset was changed.

Solution: Perform the restart procedure according to the operator's manual.

P/S 097 — P TYPE NOT ALLOWED (AUTO EXEC)

Machine type: Lathe and machining center
Meaning: A P type is invalid on restart after power-on or an emergency stop.

Solution: Start automatic operation and perform the restart procedure in the correct order.

P/S 098 — G28 FOUND IN SEQUENCE RETURN

Machine type: Lathe and machining center
Meaning: A G28 was found during the search on a restart command after power-on/emergency stop.

Solution: Perform a reference return before the restart procedure.

P/S 099 — MDI EXEC NOT ALLOWED AFTER SEARCH

Machine type: Lathe and machining center
Meaning: An MDI move command cannot be given after a program restart search has completed.

Solution: Run the program in automatic mode instead of using MDI.

Parameter Write Enable and Memory Clear

P/S 100 — PARAMETER WRITE ENABLE

Machine type: Lathe and machining center
Meaning: PWE (Parameter Write Enable) was turned on (PWE=1).

Solution: After finishing the parameter changes, set PWE back to 0 and reset the system. The alarm is persistent and will not clear until PWE is set to 0.

P/S 101 — PLEASE CLEAR MEMORY

Machine type: Lathe and machining center
Meaning: Power was cut while a program was being edited.

Solution: Set PWE=1, hold down DELETE while powering on, and clear memory (all programs will be deleted — restore from backup if you have one).

Macro Programming and Variable Errors

P/S 109 — P/S ALARM (G08 P değeri hatalı)

Machine type: Lathe and machining center
Meaning: In G08, a value other than 0 or 1 was written after P, or nothing was written at all.

Solution: Use G08 P1 (feed-forward mode) or G08 P0.

P/S 110 — DATA OVERFLOW

Machine type: Lathe and machining center
Meaning: A value on the fixed decimal-point display exceeded the allowed limit.

Solution: Reduce the value to within the valid range.

P/S 111 — CALCULATED DATA OVERFLOW

Machine type: Lathe and machining center (macro)
Meaning: The result of a macro calculation is invalid (too large or too small).

Solution: Check the variables used in the calculation.

P/S 112 — DIVIDED BY ZERO

Machine type: Lathe and machining center (macro)
Meaning: A division by zero occurred, or an invalid trigonometric operation such as tan 90°.

Solution: Make sure the denominator is not zero.

P/S 113 — IMPROPER COMMAND

Machine type: Lathe and machining center (macro)
Meaning: A function that cannot be used in a custom macro was commanded.

Solution: Use macro commands correctly.

P/S 114 — FORMAT ERROR IN MACRO

Machine type: Lathe and machining center
Meaning: An undefined H code or a format error in an expression occurred in a G25 block.

Solution: Check the macro format.

P/S 115 — ILLEGAL VARIABLE NUMBER

Machine type: Lathe and machining center
Meaning: An undefined variable number was used, or the canned-cycle header data is invalid.

Solution: Make sure the variable number is valid (#1-#999).

P/S 116 — WRITE PROTECTED VARIABLE

Machine type: Lathe and machining center
Meaning: An attempt was made to write to a write-protected variable (e.g. a system variable).

Solution: Only use variables with read/write permission.

P/S 118 — PARENTHESIS NESTING ERROR

Machine type: Lathe and machining center (macro)
Meaning: The bracket nesting limit (5 levels) was exceeded.

Solution: Arrange the brackets properly.

P/S 119 — ILLEGAL ARGUMENT

Machine type: Lathe and machining center (macro)
Meaning: The SQRT (square root) argument is negative, or a BCD/BIN conversion is invalid.

Solution: Make sure the argument is positive.

P/S 122 — DUPLICATE MACRO MODAL-CALL

Machine type: Lathe and machining center
Meaning: A modal macro call was defined twice.

Solution: Call it only once.

P/S 123 — CAN NOT USE MACRO COMMAND IN DNC

Machine type: Lathe and machining center
Meaning: A macro control command cannot be used during a DNC operation.

Solution: Avoid macro control commands during DNC.

P/S 124 — MISSING END STATEMENT

Machine type: Lathe and machining center (macro)
Meaning: A DO-END mismatch occurred.

Solution: Make sure every DO has a matching END.

P/S 125 — FORMAT ERROR IN MACRO

Machine type: Lathe and machining center
Meaning: An invalid address or expression format error occurred in a G65 call.

Solution: Check the macro call format.

P/S 126 — ILLEGAL LOOP NUMBER

Machine type: Lathe and machining center
Meaning: In a DO n command, n is something other than 1, 2 or 3.

Solution: Only use DO1, DO2 or DO3.

P/S 127 — NC MACRO STATEMENT IN SAME BLOCK

Machine type: Lathe and machining center
Meaning: An NC command and a macro command were combined in the same block.

Solution: Write them in separate blocks.

P/S 128 — ILLEGAL MACRO SEQUENCE NUMBER

Machine type: Lathe and machining center
Meaning: The sequence number specified in a GOTO is not within 0-9999, or cannot be found.

Solution: Use a valid N number.

P/S 129 — ILLEGAL ARGUMENT ADDRESS

Machine type: Lathe and machining center
Meaning: An address not permitted in the argument assignment format was used.

Solution: Use valid addresses (A, B, C, etc.).

P/S 199 — MACRO WORD UNDEFINED

Machine type: Lathe and machining center
Meaning: An undefined macro word was used.

Solution: Define the macro variables correctly.

External Alarm Messages and PMC Axis Control

P/S 130 — İLLEGAL ARGUMENT ADDRESS (CNC/PMC eksen çatışması)

Machine type: Lathe and machining center
Meaning: An axis controlled by the CNC received a command from the PMC, or vice versa.

Solution: Set the axis control authority correctly.

P/S 131 — TOO MANY EXTERNAL ALARM MESSAGES

Machine type: Lathe and machining center
Meaning: Five or more external alarm messages occurred at the same time.

Solution: Review the PMC ladder diagram and clear the alarm sources one by one.

P/S 132 — ALARM NUMBER NOT FOUND

Machine type: Lathe and machining center
Meaning: The alarm number could not be found when clearing an external alarm message.

Solution: Check the ladder diagram.

P/S 133 — ILLEGAL DATA IN EXC. ALARM MSG

Machine type: Lathe and machining center
Meaning: Invalid data in an external alarm/operator message.

Solution: Check the PMC ladder.

P/S 139 — CAN NOT CHANGE PMC CONTROL AXIS

Machine type: Lathe and machining center
Meaning: The axis selected under PMC axis control cannot be changed.

Solution: Check the PMC ladder.

Spindle and Axis Control Errors

P/S 135 — SPINDLE ORIENTATION PLEASE

Machine type: Lathe and machining center (C axis or indexing)
Meaning: A spindle indexing operation was attempted without spindle orientation.

Solution: Perform orientation with M19 first.

P/S 136 — C/H-CODE AND MOVE CMD IN SAME BLOCK

Machine type: Lathe (C axis)
Meaning: Spindle indexing addresses (C, H) and another axis move were combined in the same block.

Solution: Write them in separate blocks.

P/S 194 — SPINDLE COMMAND IN SYNCRO-MODE

Machine type: Lathe and machining center (dual spindle)
Meaning: An unsuitable command was given while the spindles were in synchronous mode.

Solution: Cancel synchronous mode first.

P/S 195 — MODE CHANGE ERROR

Machine type: Lathe and machining center (serial spindle)
Meaning: The serial spindle control mode could not be changed.

Solution: Check the PMC ladder.

P/S 197 — C-AXIS COMMANDED IN SPINDLE MODE

Machine type: Lathe (C axis)
Meaning: A C-axis move was commanded while the CON signal was off.

Solution: Switch to C-axis mode first (M??), or check the PMC signals.

Tool Geometry (Twin Turret) Errors

P/S 161 — COMMAND G68/G69 INDEPENDENTLY (TT tezgâhlar)

Machine type: TT (turret-turret) type machines
Meaning: G68/G69 was not commanded independently in balance cutting.

Solution: Use G69 after G68 and do not place another G code between them.

P/S 169 — ILLEGAL TOOL GEOMETRY DATA (TT)

Machine type: TT type machines
Meaning: Incorrect tool geometry data in interference checking.

Solution: Check the tool offsets.

High-Speed Machining (G05/G107) Errors

P/S 175 — ILLEGAL G107 COMMAND

Machine type: Machining center (cylindrical interpolation)
Meaning: Start-up or cancel conditions for cylindrical interpolation (G107) are not correct.

Solution: Call G107 in the correct way.

P/S 176 — IMPROPER G-CODE IN G107

Machine type: Machining center
Meaning: An invalid G code (e.g. G28, G76, G50, G53, etc.) was used in cylindrical interpolation mode.

Solution: Do not use these codes in G107 mode.

P/S 177 — CHECK SUM ERROR (G05 MODE)

Machine type: Machining center (high-speed machining)
Meaning: A checksum error occurred in G05 mode.

Solution: Check the program and reload it if necessary.

P/S 178 — G05 COMMANDED IN G41/G42 MODE

Machine type: Lathe and machining center
Meaning: G05 was commanded while tool radius compensation was active.

Solution: Do not use G05 without first canceling compensation.

P/S 179 — PARAM SETTING ERROR

Machine type: Lathe and machining center
Meaning: The number of controlled axes set in parameter 597 exceeded the maximum.

Solution: Set the parameter to the correct value.

General Tips for Troubleshooting Alarms

  • Note down the alarm number and the on-screen message exactly as shown; the number alone is not enough — your control's exact message narrows down the cause.
  • Record the program line (block number) where the alarm occurred; most P/S alarms highlight the relevant block on screen.
  • The same alarm number can behave differently across FANUC series; do not directly apply a fix you found online without knowing your machine's exact model and control software version.
  • If a fix requires a parameter change, back up the current parameter set first and have the change made by an authorized person.
  • When in doubt, rely on your machine builder's or FANUC dealer's official manual.

Summary

The P/S alarm codes on this page cover what is not already covered in Mentor CNC’s FANUC 0/00/0-Mate parameter guide and the G71/G72/G74/G75 cycle pages. When you hit an alarm, check this page first, or the relevant cycle page (G71, G72, G74, G75) if it’s cycle/parameter related.

Mentor CNC Disclaimer and Verification Notice

⚠️ The alarm explanations on this page are based on general FANUC P/S alarm logic, and the source document did not specify which FANUC series it applies to. Alarm behavior, message text and related parameter numbers can vary by control series (0i, 16i/18i/21i, 30i/31i/32i, etc.), software version, and the machine builder’s PMC implementation. Nothing on this page replaces your own machine’s operator and alarm manual. Before acting on any alarm, always verify the exact alarm number and message on your own machine’s screen against the manufacturer’s official manual or with authorized service. Back up parameters before changing them; run first tests in single-block mode at a low feed rate.