Panasonic CS-Z20VKR Service Manual page 131

17.4.13.2 CU-Z80VKR
Malfunction Decision Conditions

The rotation speed detected by the Hall IC during fan motor operation is used to determine abnormal fan motor.
Malfunction Caused

Operation stops due to short circuit inside the fan motor winding.

Operation stops due to breaking of wire inside the fan motor.

Operation stops due to breaking of fan motor lead wires.

Operation stops due to Hall IC malfunction.

Operation error due to faulty outdoor unit PCB.
Troubleshooting
When abnormality indication starts again.
Turn off power supply and rotate fan by hand.
Does fan rotate smoothly?
Turn power supply on and operate fan.
Does it rotate?
Turn off power supply and disconnect fan motor connector,
then turn power on.
Check the output of fan motor from outdoor PCB.
Is the motor power supply voltage 310~340 Vdc (pin 1 & 4)
generated?
Is the motor control voltage 14.6~17.0 Vdc (pin 5 & 4)
generated?
Operate the fan, is the rotation command voltage 3~5 Vdc
(pin 7 & 4) generated?
YES
NO
YES
For safety reason and to prevent
component breakdown, always switch
off the power before remove and
connect the component.
NO
Replace fan motor.
YES
Check the rotation feedback output from fan motor.
Operate the fan motor, is the rotation feedback
voltage ~8.0 Vdc (pin 6 & 4) generated?
NO
NO
NO
Replace outdoor PCB.
Replace fan motor.
131
YES
NO