Heidenhain codes
HeidenhainToolIntermediate30-120 minutes

603-0281

HEIDENHAIN 603-0281 - Tool position unknown! Position tool.

Tool position unknown! Position tool.

This error condition indicates tool position unknown! position tool. The control has detected an issue that requires attention before normal operation can resume.

Root Cause Summary

Alarm 603-0281 occurs when the TNC control has longitudinal cutting limits defined but lacks valid position coordinates for the active tool. This typically happens after power-up, tool changes, or when tool position data is corrupted in the tool table.

Safety

  • Refer to Heidenhain service manual
  • Ensure qualified technician performs repairs

Causes and Fixes

  1. 1

    Perform complete reference run

    Execute reference run sequence for all axes using softkey REF or manual reference procedure in operating mode Manual.

    Always complete reference run before any machining operations when longitudinal limits are defined

  2. 2

    Position tool to known location

    Manually jog tool to a safe, known position and execute M0 or program stop to establish current coordinates.

    Ensure adequate clearance from workpiece and fixtures during manual positioning

  3. 3

    Update tool position in TNC

    Use TOOL CALL function or execute T tool number M6 to properly register tool position with the control system.

  4. 4

    Verify position display

    Check position display shows valid coordinates in all axes before continuing with program execution.

DIY Feasiblehigh confidence

Call a technician if:

  • ·Machine parameter corruption suspected
  • ·Encoder feedback issues
  • ·Persistent alarm after all troubleshooting steps

Prevention

  • Always complete reference run after power-up
  • Maintain accurate tool table data
  • Verify tool change completion
  • Regular backup of tool tables and parameters

Common Mistakes

  • Skipping reference run procedure
  • Ignoring tool table validation
  • Attempting to run program without established tool position
  • Incorrect longitudinal limit parameter values

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