- ZU control board (ZUCB)
- Punch motor (M604)
- Check the connector connection and the wiring between ZUCB and the motor, and repair it if any abnormality.
- Check the I/O drive of the motor and the coupling of the gear, and repair/replace it if any abnormality. (Wiring diagram: ZU-608: 5-B)
- Replace M604.
- Replace ZUCB.
