Midea M2OC-18HFN1-M, Service Manual

Page: 46 / 128

9.4.1.4 Indoor fan speed has been out of control
diagnosis and solution.
Malfunction decision
conditions When indoor fan speed keeps too low (300RPM) for certain time, the unit
will stop and the LED will display the failure.
Supposed causes
●
Wiring mistake
●
Fan ass’y faulty
●
Fan motor faulty
●
PCB faulty
Trouble shooting:
Shut off the power supply
and turn it on 1 minute
later. Is it still displaying
the error code?
Shut off the power supply,
rotate the fan by hand.
Does it rotate properly?
The unit operates normally.
Find out the cause and
have it solved. For
example, check
whether the fan is
blocked or the bearing
is broken?
Check the wires of fan
motor. Are all the
connections good?
No
Yes
No
Correct the connections. No
Yes
Check whether the main PCB is
normal through index 2?
Yes
Yes
Check whether the fan
motor is normal through
index 1?
Yes
Replace the fan
motor
Replace the
main PCB.
The
malfunction is
solved?
No
No
If the
malfunction is
still existing,
replace the
main PCB
No