• Fan motor does not operate or stops operating shortly after starting the operation.

D Check of outdoor fan motor

Check the connection between the connector CN931 and CN932.

Is the resistance between each terminal Yes of outdoor fan motor normal?

No

(Fixed to either 5V or 0V DC) No

Disconnect CN932 from outdoor electronic control P.C. board, and turn on the power supply.

Rotate the outdoor fan motor manually and measure the voltage of CN931.

Between 1(+) and 5(-)

Between 2(+) and 5(-)

Between 3(+) and 5(-)

Does the voltage between each terminal become 5V DC and 0V DC repeatedly?

No

Yes

Replace the outdoor DC fan motor.

Does the outdoor fan motor rotates smoothly?

Yes

Replace the outdoor electronic control P.C. board.

Outdoor unit does not operate. (LED display: display OFF)

E Check of power supply

Check the connecting of parts of main power supply circuit.

Turn on power supply.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Is there voltage of 230V AC in the

No

 

 

 

 

 

Check the power supply cable.

power supply terminal block?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Is the output voltage from the noise

No

 

Is fuse (F64) blown?

No

filter P.C. board 230V AC?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

Replace the fuse.

 

 

 

 

 

 

 

 

 

 

Replace the noise filter P.C. board.

Is the input voltage to the power board 230V AC?

Yes

Is the input voltage to the outdoor electronic control P.C. board 325V DC?

Yes

No

Replace the reactor.

 

No

Replace the power board.

Replace the outdoor electronic control P.C. board.

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Mitsubishi Electronics MUZ-GB50VA service manual Check of outdoor fan motor, Check of power supply