INVERTER COOLING FAN FAILURE
Fanuc · Series 0i-D/0i Mate-D Maintenance
What does 444 n AXIS: INV. COOLING FAN FAILURE mean?
This warning signal on the Fanuc Series 0i-D/0i Mate-D αi servo system indicates a failure of the inverter cooling fan. This condition will lead to an inverter overheat alarm if not addressed, as reported by the servo amplifier (SVWRN4 active).
Common Causes
- Cooling fan motor failure in the inverter unit.
- Obstruction or blockage of the fan's intake or exhaust preventing proper airflow.
- Loose or damaged electrical connection to the inverter cooling fan.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Visually inspect the inverter cooling fan for any blockages (e.g., dust, debris) or physical damage to the fan blades.
- 2
Check the electrical connection to the fan motor for proper seating and continuity.
- 3
Attempt to manually spin the fan blades (with power off) to check for binding or excessive resistance.
- 4
Verify the fan's operation by observing rotation during system power-on (if safe to do so).
- 5
If the fan is confirmed to be faulty or non-operational, replace the inverter cooling fan unit.