Panasonic CS-E18QB4RW Service Manual page 68

15.4.9 H27 (Outdoor Air Temperature Sensor Abnormality)
Malfunction Decision Conditions

During startup and operation of cooling and heating, the temperatures detected by the outdoor air temperature
sensor are used to determine sensor errors.
Malfunction Caused

Faulty connector connection.

Faulty sensor.

Faulty PCB.
Troubleshooting
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