Trouble Shooting - Mitsubishi SEZ-A12AR Technical & Service Manual

6-3. Trouble shooting

(1) In case of being indicated irregularity on the self diagnoses
Check
Phenomenon
code
6800 Mis-wiring
Indoor-outdoor
signal error
5102 Pipe temperature thermistor
/ Liquid.
Condenser / evaporator
temperature thermistor
Outdoor thermistor
5101
Room temperature
thermistor
1503 Freezing protection is
working.
0405 Malfunction of outdoor unit
1501
4210
Cause
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.
Trouble of the Indoor controller
board.
Mis-connecting of the pipe
temperature thermistor / Liquid.
Trouble of the pipe temperature
thermistor / Liquid.
Trouble of the Indoor controller
board.
Mis-connecting of the condenser /
evaporator temperature thermistor.
Trouble of the condenser / evaporator
temperature thermistor.
Trouble of the Indoor controller
board.
Mis-connecting of the outdoor
thermistor.
Trouble of the outdoor thermistor.
Trouble of the outdoor inverter P.C.
board.
Mis-connecting of the room
temperature thermistor.
Trouble of the room temperature
thermistor.
Trouble of the Indoor controller
board.
1) Short cycle of air cycle
2) Dirty air filter
3) Damaged fan
4) Abnormal refrigerant
Malfunction of outdoor unit
12
Countermeasure
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.
Exchange the Indoor controller board.
Reinsert the connector (CN21).
Check the resistance value of the thermistor.
Exchange the Indoor controller board.
Reinsert the connector (CN29).
Check the resistance value of the thermistor.
Exchange the Indoor controller board.
Reinsert the connector.
Check the resistance value of the thermistor.
Exchange the outdoor inverter P.C. board.
Reinsert the connector (CN20).
Check the resistance value of the thermistor.
Exchange the Indoor controller board.
1) Clear obstructions from air cycle.
2) Clean the air filter
3) Check the fan
4) Check the refrigerant temperature.
Refer to the TECHNICAL & SERVICE MANUAL
of outdoor unit.