Panasonic CS-E12RB4UW Service Manual page 69

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
When abnormality indication starts again.
Check the connector connection:
Turn off the power.
Check the connector connection.
Is the connector connection normal?
Check the outdoor air temperature sensor:
Plug out connector from the outdoor unit PCB.
Measure the resistance of the outdoor air temperature
sensor.
Is the measured resistance of the outdoor air temperature
sensor matches the value specified in its characteristic
chart?
Sensor (Thermistor)
Characteristics
70


60
50
40

30

20
10
0
-10 0 10
(14) (32) (50)
Temperature °C (°F)
YES
YES
Outdoor Air Sensor
Outdoor Heat Exchanger
Sensor
20 30 40 50
(68) (86) (104) (122)
For safety reason and to prevent component
breakdown, always switch off the power
Caution
before remove and connect the component.
NO
Connector poor contact.
Correct the connection.
NO
Defect in outdoor air temperature sensor.
Replace the outdoor air temperature sensor.
Defect in outdoor unit PCB.
Replace the outdoor unit PCB.
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