Mitsubishi Electric PUHZ-W50VHA2R1 Service Manual page 24

8-4-1. Check method of DC fan motor (fan motor/outdoor controller circuit board)
Notes
1
· High voltage is applied to the connector (CNF1, 2) for the fan motor. Pay attention to the service.
· Do not pull out the connector (CNF1, 2) of the motor with the power supply on.
(It may damage the outdoor controller circuit board and fan motor.)
Self check
2
Symptom: The outdoor fan cannot rotate.
Check fuse (F5) on outdoor controller
circuit board.
Is the fuse normal?
Yes
Wiring contact check
Check contact of fan motor connector
(CNF1) (CNF2)
Is there contact failure?
No
Power supply check
Measure the voltage on the outdoor controller circuit.
(Remove the connector CNF1)
TEST POINT
1 V 280–380 V DC (between 1 (+) and 4 (−) of CNF1)
DC
2 V 15 V DC
CC
Is the voltage normal?
No
Replace the outdoor controller circuit board.
fan motor rotation.
Check
Fail
Replace the fan motor.
OCH605A
No
Replace the fan motor.
Replace the outdoor controller circuit board.
Yes
Recover wiring.
(between 5 (+) and 4 (−) of CNF1)
Yes
Replace fan motor.
Check
Replace the outdoor controller circuit board.
OK
END
<How to check the resistance>
To measure the resistance, connect the negative (−)
end of the tester to pin 4.
FAN MOTOR
Measuring points
Pin 1–pin 4 400 to 500 k"
Pin 5–pin 4
Pin 6–pin 4
Pin 7–pin 4
OK
fan motor rotation.
Fail
24
RG61N769
Resistance
1.2 k"
155 k"
∞
END