What causes Siemens SINUMERIK alarm 10242?

The internal state of the indicated channel is not uniquely defined (e.g. in initialization mode or waiting for an acknowledgement from the sequence control system).

How do I fix Siemens SINUMERIK alarm 10242?

1. You can change the mode by pressing the Reset key and repeating the mode selection. 2. Clear alarm with the Delete key or NC START

axismd.ai

Siemens SINUMERIK Controller

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

Alarm 10242

Siemens 10242 - [up to SW 3.x only] Mode group mode change in channel not

Alarm 10242 occurs when attempting a mode change within a mode group while channel %1 is active, but the mode change cannot be executed due to conflicting channel states or active operations. This is specific to SINUMERIK 840D systems running software version 3.x or earlier, indicating that synchronized channels within the same mode group are preventing the requested mode transition.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

10242

Siemens 10242 - [up to SW 3.x only] Mode group mode change in channel not

[up to SW 3.x only] Mode group mode change in channel not

Root Cause Summary

Alarm 10242 occurs when attempting a mode change within a mode group while channel %1 is active, but the mode change cannot be executed due to conflicting channel states or active operations. This is specific to SINUMERIK 840D systems running software version 3.x or earlier, indicating that synchronized channels within the same mode group are preventing the requested mode transition.

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.

Causes and Fixes

1
Press RESET to clear the alarm and stop any active program execution in channel %1.
2
Check HMI for channel %1 status - verify it shows 'Program stopped' or 'Reset' state, not 'Active' or 'Interrupted'.
3
Review NC program for missing M30 or M02 at program end, or verify RESET was issued after last program run.
4
Retry mode change after confirming channel is completely stopped with no buffered blocks remaining.

Service Recommended confidence

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.