| Symptom | Section in Service Manual | Solution | | :--- | :--- | :--- | | "Service Due" on screen | Chapter 5: Preventive Maintenance | Perform 2000-hour service; reset maintenance counter. | | O2 concentration inaccurate (90% vs set 50%) | Chapter 8: Pneumatic System | Replace O2 cell; run AutoCalibration routine. | | High-frequency oscillation not engaging | Chapter 12: Valve Assembly | Inspect HF valve diaphragm for tears; replace seal. | | Touchscreen unresponsive | Chapter 14: HMI Board | Disconnect ribbon cable; re-seat or replace digitizer. | | Fan error at startup | Chapter 10: Cooling System | Clean blower fan filter; replace 24V DC fan module. |
Proper disassembly is required for deep cleaning and component replacement. Babylog® VN500