Siemens SINUMERIK codes
AxisMD

axismd.ai

Siemens SINUMERIK Controller

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

Alarm 401602

Siemens 840D 401602 - Impermissible axis no. parameter in FC 16

Siemens SINUMERIK alarm 401602: Impermissible axis no. parameter in FC 16. An impermissible or invalid parameter was passed to PLC function block FC16. This indicates a PLC programming error or configuration mismatch in the machine tool builder ladder program.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

401602

Siemens 840D 401602 - Impermissible axis no. parameter in FC 16

Impermissible axis no. parameter in FC 16

Siemens SINUMERIK alarm 401602: Impermissible axis no. parameter in FC 16. An impermissible or invalid parameter was passed to PLC function block FC16. This indicates a PLC programming error or configuration mismatch in the machine tool builder ladder program.

Safety

  • Refer to Siemens documentation
  • Ensure qualified technician performs repairs

Common Causes

  • Invalid axis number passed to FC16 in the PLC program
  • FC16 called with a parameter that exceeds the valid range for this SINUMERIK configuration
  • PLC program version mismatch — FC16 call parameters not updated after a machine configuration change
  • Number of configured axes in SINUMERIK does not match the FC16 parameter
  • PLC program downloaded with incorrect machine data for this specific machine tool

Troubleshooting Steps

  1. 1Check the SINUMERIK PLC alarm details for the specific parameter value that caused the error.
  2. 2Review the PLC program — find the call to FC16 and verify the parameter values are within valid range.
  3. 3Compare the FC16 parameter against the actual number of configured axes in the SINUMERIK machine data.
  4. 4If the PLC program was recently modified or the machine configuration changed, verify FC16 calls were updated accordingly.
  5. 5Contact the machine tool builder if the PLC program source is not available for review.

Seeing Multiple Alarms?

Seeing another alarm with this one? Enter the code.

Get machine-aware diagnosis

AxisMD logs alarms against your actual machines, tracks patterns, and gives AI context your manual doesn't have.

Start free

Was this guide helpful?

Always verify with your machine manual or a certified technician before performing service procedures.