Panasonic CS-PS9NKH Service Manual page 73

14.4.10 H33 (Unspecified Voltage between Indoor and Outdoor)
Malfunction Decision Conditions
The supply power is detected for its requirement by the indoor/outdoor transmission.
Malfunction Caused
Wrong models interconnected.
Wrong indoor unit and outdoor unit PCBs used.
Indoor unit or outdoor unit PCB defective.
Troubleshooting
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