Mitsubishi Electric Mr.Slim PMH-P25BA Service Manual page 18

Check method of indoor fan motor (fan motor / control p.c.board)
1 Notes
· High voltage is applied to the connecter (FAN) for the fan motor. Give attention to the service.
· Do not pull out the connector (Fan) for the motor with the power supply on.
(It causes trouble of the control
2
Self check
Conditions : The indoor fan cannot turn around.
Wiring contact check
Contact of fan motor connector (FAN)
Contact of power supply cable.
Was contact caused good?
Yes
Fan motor check
Measure the resistance between the fan motor connecter 1(+) and 3( ).
(With the connecter is pulled out from the
Is the resistance 1M " or more?
Yes
Power supply check
Check the voltage in the indoor control
Approx. 310~340V between the connecter (FAN) 1(+) and 3( ).
Approx. 1~3V between the connecter (FAN) 5(+) and 3( ).
The voltage between the 5 and 3 is a value during the fan motor operation.
In the case that the fan motor off, the voltage is 0V.
Is the voltage normal?
Yes
Fan motor position sensor signal check
Turn around the fan motor more than one revolution slowly, and check
the voltage between the connecter (FAN) 6(+) and 3( ).
Dose the voltage repeat DC0V and DC15V?
Yes
Replacement of the indoor control p.c.board
p.c.board)
Wiring recovery
No
p.c.board)
Trouble of the fan motor Replacement of the motor
No
p.c.board
Trouble of the indoor p.c.board
No
Replacement of the indoor control p.c.board
Trouble of the fan motor
No
Replacement of the motor
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