Daikin AT12BV1LS Pocket Manual page 33

Troubleshooting
5.1.5 Thermistor or Related Abnormality
(Indoor Unit)
Remote
Controller
Display
Method of
Malfunction
Detection
Malfunction
Decision
Conditions
Note: The values vary slightly in some models.
Supposed
Causes
Trouble
shooting
Check No.6
Refer to
P.157
32
C4, C9
The temperatures detected by the thermistors are used
to determine thermistor errors.
When the thermistor input is more than 4.96 V or less
than 0.04 V during compressor operation*.
* (reference)
When above about 212°C (less than 120 ohms) or below
about -50°C (more than 1,860 kohms).
Faulty connector connection
Faulty thermistor
Faulty PCB
Be sure to turn off power switch before connect or
Caution disconnect connector, or parts damage may be occurred.
Check the connector
connection.
Is it normal?
YES
Check No. 6
Thermistor resistance check
Is it normal?
YES
C4 : Heat exchanger temperature thermistor
C9 : Room temperature thermistor
NO
Correct the connection.
NO
Replace the thermistor.
(Replace the indoor
unit PCB.)
Replace the indoor
unit PCB.
Service Diagnosis
Si10-417
(R1403)