Service manual    DM16-01.01.11-01en 
34    Multi DC inverter R410A. Outdoor unit 
11. Troubleshooting 
11.1 Indoor unit error code explanation: 
 
For MTBI-18HWDN1-Q 
MALFUNCTION  RUN  Timer  DEF  Alarm 
DISPLAY 
 DIGITAL 
TUBE 
Open or short circuit of T1 temperature sensor  ☆  X X  X  E0 
Open or short circuit of T2 temperature sensor  X  X  ☆  X  E1 
Indoor / outdoor units communication error  X  ☆ X  X  E2 
Full-water malfunction  X  X  X  ☆  E3 
Indoor EEPROM malfunction 
☆  ☆ 
X X E4 
IPM module protection  ☆  X  X  O  E5 
Open or short circuit of T3 or T4 temperature sensor or 
Outdoor EEPROM malfunction 
☆
  O  X X E6 
Outdoor fan speed has been out of control  ☆  O  ☆  X  E7 
Indoor fan speed has been out of control  ☆  O  O X F5 
Voltage protection  ☆  O  X  O  P0 
Outdoor unit over-current protection  ☆  ☆  ☆ X P2 
Inverter compressor drive protection  ☆  ◎  X  X  P4 
Mode conflict  ☆ X  O  O  P5 
O (on)   X(off)  ☆(flash at 2Hz) ◎(flash at 0.5Hz) 
 
For other type   
Malfunction  Error Code  Timer Lamp 
Operation Lamp 
(flashes) 
Indoor EEPROM malfunction  E0  X  1 
Communication malfunction between indoor and outdoor units  E1  X  2 
Indoor fan speed has been out of control  E3  X  4 
Open or short circuit of T1 temperature sensor  E4  X  5 
Open or short circuit of T2 temperature sensor  E5  X  6 
Water level alarm  EE X  8 
Overcurrent protection (For some units)  F0  O  1 
Open or short circuit of T4 temperature sensor  F1  O  2 
Open or short circuit of T3 temperature sensor  F2  O  3 
Open or short circuit of T5 temperature sensor  F3  O  4 
Outdoor EEPROM malfunction (For some units)  F4  O  5 
Outdoor fan speed is out of control  F5  O  6 
Open or short circuit of T2B temperature sensor (For free-match indoor 
units) 
F6  O  7 
Communication error between auto-lifting panel and slim cassette (For 
slim cassette with auto-lifting panel) 
F7 O
  8 
Auto-lifting panel is faulty (For slim cassette with auto-lifting panel)  F8  O  9 
Auto-lifting panel is not closed (For slim cassette with auto-lifting panel)  F9  O  10 
IPM module malfunction  P0  ☆  1