Samsung AQ09VFUAGM/CV Service Manual page 74

Indoor fan motor speed detecting error (BLDC fan)
Indoor display
1.Checklist :
1) Is the indoor units fan motor properly connected with the connector(CN72)?
2) Is the AC voltage correct?
2. Troubleshooting procedure
Restart a er power o .
Does the fan rotate?
YES
Reassemble the fan wire and input the power again
Is the fan error appeared again?
YES
Is the voltage of CN72 #1-#3 over
250Vdc
YES
Is the voltage of CN72 #3-#5 and
#3-#6 with in 1Vdc~15Vdc during
the opera on?
YES
PBA problem or Motor problem
Change the PBA rst and check the opera on
Exchange the Fan motor
Indoor fan error
NO
Is there short among each pin
NO
Terminate the
service
NO
NO
Power o and Separate the Fan motor wire from
CN72 on Indoor PBA
#1~#6
NO
Follow the check procedure of Indoor unit power
supply error check
Exchange the Indoor PBA
YES
Exchange the Fan
motor
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