York YH9FXC24BAH--FX Service Manual page 39

11.4.3 Indoor AC fan motor malfunction
Indoor Display E14
Method of The rotation speed detected by the Hall IC during fan motor operation is
used to determine
Malfunction abnormal fan motor operation
Detection
Malfunction when the detected rotation feedback signal don't received in 2 minutes
Decision
Conditions
Supposed ■ Operation halt due to breaking of wire inside the fan motor.
Causes ■ Fan motor overheat protection
■ Operation halt due to breaking of the fan motor lead wires
■ Detection error due to faulty indoor unit PCB
Troubleshooting
Check whether terminals
on indoor pcb is well?
Electrify the machine again and turn it on in the cooling operation,
Measure voltage between the positions 1and 3 of Terminal CN5 on
the indoor PCB
the voltage is about 90-220vac
check whether motor can run
when turn on the unit
the indoor motor is damaged and need replace
* Caution Be sure to turn off power switch before connect or disconnect
connector,
Yes
NO
or else parts damage may be occurred.
Pull out the terminals on the indoor
No
mainboard and reinsert them.
NO
Yes
Measure whether there is voltage pulse(0-5VDC)
Yes
between the positions middle wire and black wire
of Terminal CN2 on the indoor PCB
NO
the indoor pcb is damaged and need replace
37
Service Diagnosis
Is it ok?
Yes
Domestic air conditioner