16 Troubleshooting 
16.1    Indoor unit error code explanation: 
For 15C/Cassette 
Indoor EEPROM malfunction 
Communication malfunction between indoor and outdoor units 
Indoor fan speed has been out of control 
Open or short circuit of T1 temperature sensor 
Open or short circuit of T2 temperature sensor 
Overcurrent protection (For some units) 
Open or short circuit of T4 temperature sensor 
Open or short circuit of T3 temperature sensor 
Open or short circuit of T5 temperature sensor 
Outdoor EEPROM malfunction (For some units) 
Outdoor fan speed is out of control 
Open or short circuit of T2B temperature sensor 
Over voltage or over low voltage protection 
Too low ambient temperature protection 
Inverter compressor drive protection 
Low pressure protection of compressor 
O (on)      X(off)    ☆(flash at 2Hz) 
Indoor EEPROM malfunction 
Communication malfunction between indoor and outdoor units 
Indoor fan speed has been out of control 
Open or short circuit of T1 temperature sensor 
Open or short circuit of T2 temperature sensor 
Overcurrent protection (For some units) 
Open or short circuit of T4 temperature sensor 
Open or short circuit of T3 temperature sensor 
Open or short circuit of T5 temperature sensor 
Outdoor EEPROM malfunction (For some units) 
Outdoor fan speed is out of control 
Open or short circuit of T2B temperature sensor (For free-match indoor units) 
Over voltage or over low voltage protection