York DHP30NWB21SDCP30NWB21SDHP36NWB21SDCP36NWB21S Service Manual page 51

2.Malfunction of Blocked Protection of IDU Fan Motor H6
Test whether the voltage between terminal 1 and terminal 2
Start
Turn the fan blades
by hand under
power-off condition
Whether the fan blades
can run smoothly?
Yes
Under power-off condition,
check whether the wiring terminal
between indoor fan and main
board is loose.
No
Connect power and restart the unit.
of motor interface is within 280~310VDC.
Yes
Then check whether the voltage
between terminal 2 and terminal 3
of the motor interface is 15VDC.
Yes
Then check whether there is voltage
between terminal 2 and terminal 4
of the motor interface.
Yes
It's the malfunction of motor.
Replace a new motor that is
of the same model.
Adjust the motor and blade
assembly so that rotor can run
No
smoothly.
to check whether the
No
Reinsert the wiring
Yes
terminal of indoor fan.
to check whether the
No
It's the malfunction of main board.
No Replace a new main board that is
of the same model.
It's the malfunction of main board.
Replace a new main board that is
No
of the same model.
It's the malfunction of main board.
Replace a new main board that is
No
of the same model.
Turn unit on
malfunction is
eliminated.
Turn unit on
Yes
malfunction is
eliminated.
End
Yes
44