Mitsubishi Electric PKFY-P32VHM-ER2 Technical & Service Manual page 21

8-1-3. DC Fan motor (fan motor/indoor controller circuit board)
Check method of DC fan motor (fan motor/indoor controller circuit board)
Notes
· High voltage is applied to the connecter (CNMF) for the fan motor. Pay attention to the service.
· Do not pull out the connector (CNMF) for the motor with the power supply on.
(It causes trouble of the indoor controller circuit
Self check
Symptom : The indoor fan cannot turn around.
Wiring contact check
Contact of fan motor connector (CNMF)
Is there contact failure?
No
Power supply check (Remove the connector (CNMF))
Measure the voltage in the indoor controller circuit
TEST POINT
: V (between 1 (+) and 3 (-) of the fan connector): V
DC
TEST POINT
: V (between 4 (+) and 3 (-) of the fan connector): V
CC
Is the voltage normal?
Yes
Sensor signal check
Measure the voltage between CNMF
and DC 15V in the indoor controller circuit board.
Does the voltage repeat
DC 0V and DC 15V?
Yes
Replace indoor
controller board
Check the operation
NG
Replace the fan motor.
OCH442B
board and fan motor.)
Wiring recovery
Yes
board.
No
and DC 0V
No
OK
END
21
DC310~340V
DC
DC15V
CC
Indoor controller board fuse check
Is the fuse normal?
Yes
Replace indoor controller board.
Check the operation
NG
Replace the fan motor
Replace the fan motor
Check the operation
NG
Replace indoor controller board.
No
Replace the fuse
Check the operation
NG
OK
END
OK
END
OK
END