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7.2  Indoor Unit Error Display 
For Old Console series 
MFAU-12HRFN1-M, MFAU-12HRFN1-M(B); 
Indoor room temperature sensor (T1 ) malfunction 
Evaporator coil temperature sensor (T2) malfunction 
Communication malfunction between indoor and outdoor units 
Low ambient temperature cut off in heating 
Indoor unit EEPROM parameter error 
Outdoor fan speed malfunction 
Inverter module (IPM) malfunction 
Outdoor temperature sensor(coil sensor T3 or ambient temperature 
sensor T4) malfunction or Outdoor unit EEPROM parameter error 
Compressor top high temperature protection (OLP) 
Compressor drive protection 
Indoor units mode conflict 
Indoor fan speed malfunction 
★ flash at 5Hz,  light, X extinguished, ◎flash at 0.5Hz 
For Old Duct/Cassette/Floor Ceiling 
MTBU-12HRDN1-M, MTBU-12HRDN1-M(B), MTBU-18HRDN1-M, MTB-24HRFN1-MW; 
MCA2U-12HRFN1-M, MCA2U-12HRFN1-M(B), MCA2U-18HRFN1-M, MCD-24HRFN1-MW; 
MUBU-12HRFN1-M, MUBU-12HRFN1-M(B), MUBU-18HRFN1-M, MUE-24HRFN1-MW; 
Indoor room temperature sensor (T1 ) 
malfunction 
Evaporator coil temperature sensor 
(T2) malfunction 
Communication malfunction between 
indoor and outdoor units 
Water-level alarm malfunction