Midea MSH-07CRN1, MSH-07HRN1, MSH-09CRN1, MSH-09HRN1, MSH-12CRN1, MSH-12HRN1 Manual page 358

8.3.3 Failure phenomenon
Indoor fan speed has been out of control for over 1 minute
Indoor room temp. or evaporator sensor is open circuit or short circuit
Over current protection of the compressor occurs 4 times
EEROM error
No over-zero signal
r Extinguish
Flash at 5Hz
8.3.3.1 Operation lamp flashes and Timer lamp off.
Is connector connection good?
Yes
Is voltage being applied to the fan motor?
Yes
Fan motor is defective
8.3.3.2 Operation lamp flashes and Timer lamp on.
Is connection to connector good?
Yes
Replace the sensor
8.3.3.3 Operation lamp off and Timer lamp flashes
Operation lamp off and Timer lamp flashes
After changing the main control board, check if the failure releases
The voltage of power supply is too low (less than 187V)?
8.3.3.4 Operation lamp on and Timer lamp flashes
EEROM error, indoor PCB is defective.
8.3.3.5 Operation lamp flashes, Timer lamp flashes .
This is alarm signal when the main chip can't detect over-zero signal. When such failure occurs, the main
control board must have fault.
Failure phenomenon
No
Yes
Power supply fault
Operation lamp
No
Repair the connector
No
Indoor PCB is defective
No
Repair connector
.
Yes
No
Outdoor unit fault (such as the compressor)
28
Timer lamp
X
On
X
On
Yes
Indoor PCB is defective