- Paper feed assist fan /Fr2 (FM23)
- Printer control board (PRCB)
- Check the connector connection and the wiring between PRCB and the fan, and repair it if any abnormality.
- Rotate the fan or I/O by hand, and repair it if any abnormality. (Wiring diagram: Main body (3/4): 23-A).
- Replace FM23.
- Replace PRCB.
