Mitsubishi Electric SEZ Series Technical & Service Manual page 38

[ VII TROUBLESHOOTING ]
For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table.
LED 1 (power for microcomputer)
LED 2 (power for remote controller)
LED 3 (communication between indoor and outdoor units)
HWE21010
Indicates whether control power is supplied. Make sure that this LED is always lit.
Indicates whether power is supplied to the remote controller. This LED lights only in the case of
the indoor unit which is connected to the outdoor unit refrigerant address "0".
Indicates state of communication between the indoor and outdoor units. Make sure that this LED is
always blinking.
- 35 - 35
GB