Siemens SINUMERIK codes
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Siemens SINUMERIK Controller

Program/G-code · Intermediate · 30-120 minutes

Alarm 4181

Siemens 4181 - Invalid assignment of an M auxiliary function number

In MD22254 $MC_AUXFU_ASSOC_M0_VALUE or MD22256 $MC_AUXFU_ASSOC_M1_VALUE, a number has been specified for the configuration of a new predefined M function which is occupied by the system, and cannot be used for an assignment. (M0 to M5, M17, M30, M40 to M45) Control reaction: Mode group not ready. Channel not ready. NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

4181

Siemens 4181 - Invalid assignment of an M auxiliary function number

Invalid assignment of an M auxiliary function number

In MD22254 $MC_AUXFU_ASSOC_M0_VALUE or MD22256 $MC_AUXFU_ASSOC_M1_VALUE, a number has been specified for the configuration of a new predefined M function which is occupied by the system, and cannot be used for an assignment. (M0 to M5, M17, M30, M40 to M45) Control reaction: Mode group not ready. Channel not ready. NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm.

Safety

  • Only qualified personnel should diagnose and clear control alarms; follow the machine builder's safety procedures and lockout/tagout where hardware work is required.

Common Causes

  • In MD22254 $MC_AUXFU_ASSOC_M0_VALUE or MD22256 $MC_AUXFU_ASSOC_M1_VALUE, a number has been specified for the configuration of a new predefined M function which is occupied by the system, and cannot be used for an assignment. (M0 to M5, M17, M30, M40 to M45)

Troubleshooting Steps

  1. 1Configure an M function in machine data MD22254 $MC_AUXFU_ASSOC_M0_VALUE or MD22256 $MC_AUXFU_ASSOC_M1_VALUE which is not occupied by the system (M1 to M5, M17, M30, M40 to M45).
  2. 2Switch control OFF - ON

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