SiUS181305E
Troubleshooting for CTXS, FTXS, CDXS, FDXS Series
Troubleshooting
164
4.4
Thermistor or Related Abnormality
Error Code
C4, C9
Method of Error
Detection
The temperatures detected by the thermistors are used to determine thermistor errors.
Error Decision
Conditions
The thermistor input is more than 4.96 V or less than 0.04 V during compressor operation.
Supposed
Causes
Disconnection of connector
Defective thermistor corresponding to the error code
Defective indoor unit PCB
Troubleshooting
Check No.01
Refer to P.165
C4
: Indoor heat exchanger thermistor
C9
: Room temperature thermistor
YES
(R15717)
NO
YES
NO
Caution
Correct the connection.
Replace the thermistor.
(Replace the indoor unit PCB.)
Replace the indoor unit PCB.
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Check the connection of
connectors.
Normal?
Check No. 01
Check the thermistor resistance
value.
Normal?