MXS Service Manual

SiUS121736EA Troubleshooting for SA Indoor Unit
Service Diagnosis 168
Troubleshooting
Check No.02
Refer to P.210
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Correct the power
supply.
NO
Check the power supply voltage.
YES
NO
Replace the indoor
fan motor.
Does the fan rotate
smoothly?
Rotate the fan by hand.
Turn on the power on again and
start operation.
YES
Is the
voltage
fluctuation within
±10% from the rated
value?
Check No.02
Check the output of the fan motor
connector.
YES
YES
NO
NO
Note: The motor may break when the
motor connector is disconnected
while the power is turned on.
(Be sure to turn off the power
before reconnecting the
connector.)
Replace the indoor
unit PCB (control
PCB).
Replace the indoor
unit PCB (control
PCB).
Motor
power supply voltage
290 ~ 330 VDC or
more?
(R24054)
YES
NO
Replace the indoor
unit PCB (control
PCB).
Replace the indoor
fan motor.
Motor
control voltage 15 VDC
generated?
Rotation
command
voltage 0 ~ 2 VDC
when stopped, 2 ~ 5 VDC
when operated
OK?
NO
YES
YES
NO
Check the connector for
connection.
Foreign matters in or
around the fan?
Correct the
connection.
Remove the foreign
matters.
Turn off the power supply.
(Unplug the power cable or turn
the breaker off.)