Mitsubishi SEZ-A12AR - Troubleshooting Specific Issues

12
6-3. Trouble shooting
(1) In case of being indicated irregularity on the self diagnoses
Mis-wiring6800
5102
5101
Indoor-outdoor
signal error
Wiring between the indoor and
outdoor is coming off.
Difference of wiring polarity
between the indoor and outdoor.
Trouble of the outdoor inverter
P.C. board.
Check the wiring out between the indoor and
outdoor.
Check the outdoor inverter P.C. board. Refer to the
TECHNICAL & SERVICE MANUAL of outdoor unit.
Trouble of the Indoor controller
board.
Exchange the Indoor controller board.
Pipe temperature thermistor
/ Liquid.
Mis-connecting of the pipe
temperature thermistor / Liquid.
Reinsert the connector (CN21).
Trouble of the pipe temperature
thermistor / Liquid.
Trouble of the Indoor controller
board.
Exchange the Indoor controller board.
Check the resistance value of the thermistor.
Room temperature
thermistor
Mis-connecting of the room
temperature thermistor.
Reinsert the connector (CN20).
Trouble of the room temperature
thermistor.
Trouble of the Indoor controller
board.
Exchange the Indoor controller board.
Check the resistance value of the thermistor.
Condenser / evaporator
temperature thermistor
Mis-connecting of the condenser /
evaporator temperature thermistor.
Reinsert the connector (CN29).
Trouble of the condenser / evaporator
temperature thermistor.
Trouble of the Indoor controller
board.
Exchange the Indoor controller board.
Check the resistance value of the thermistor.
Phenomenon
Check
code
Cause Countermeasure
1503
0405
1501
4210
Freezing protection is
working.
1) Short cycle of air cycle
2) Dirty air filter
3) Damaged fan
4) Abnormal refrigerant
1) Clear obstructions from air cycle.
2) Clean the air filter
3) Check the fan
4) Check the refrigerant temperature.
Malfunction of outdoor unit Malfunction of outdoor unit Refer to the TECHNICAL & SERVICE MANUAL
of outdoor unit.
Outdoor thermistor Mis-connecting of the outdoor
thermistor.
Reinsert the connector.
Trouble of the outdoor thermistor.
Trouble of the outdoor inverter P.C.
board.
Exchange the outdoor inverter P.C. board.
Check the resistance value of the thermistor.
OC303-A-1.qxp 04.9.21 4:08 PM Page 12