Thermistor Or Related Abnormality - Daikin 4MXL-T Series Service Manual

Troubleshooting for RA Indoor Unit
5.4

Thermistor or Related Abnormality

C4, C9
Error Code
Method of Error The temperatures detected by the thermistors determine thermistor errors.
Detection
Error Decision The voltage between the both ends of the thermistor is either 4.96 V or more, or 0.04 V or less with
Conditions the power on.
Supposed
 Disconnection of connector
Causes  Defective thermistor(s)
 Defective indoor unit PCB
Troubleshooting
C4 : Indoor heat exchanger thermistor
C9 : Room temperature thermistor
Reference
Check No.01 Refer to P.232
Note
When replacing the defective thermistor(s), replace the thermistor as ASSY.
172
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Check the connection of
connectors.
Normal?
YES
Check No. 01
Check the thermistor resistance
value.
Normal?
YES
NO
NO
SiUS121827E
Correct the connection.
Replace the defective
thermistor(s).
Replace the indoor unit PCB
(control PCB).
(R21870)
Part 6 Service Diagnosis