Did this error happen suddenly during operation, or for a long period?
Shut off the main breaker at the back of the machine cabinet.
The screen appears immediately after the initial BIOS/Power-On Self Test (POST) and before the full CNC or Manual Guide i interface loads. fanuc starting system software please wait
Follow these diagnostic steps from simplest to most advanced to resolve the issue. Step 1: Remove External Media and Power Cycle
The FANUC power supply unit must deliver exceptionally clean, stable DC voltages (+5V, +24V, etc.) to the control boards. If a capacitor inside the PSU fails, the voltage may drop just enough to prevent the CPU from executing high-load memory transfers, locking up the system. Step-by-Step Troubleshooting Guide Did this error happen suddenly during operation, or
Ensure the incoming 3-phase power and the CNC power supply unit (PSU) outputs are stable and within specification. 🔍 Visual Inspection of the CNC Cabinet
During this process, the FANUC system is: Follow these diagnostic steps from simplest to most
Re-enter the Boot System menu and select to load your historical factory backups. When to Call a Professional
If you successfully reach the Boot System screen, the core hardware is operational, pointing to a file or memory corruption issue.