Haier 1U18BR4EAA Service Manual page 19

8.4.2.3 Indoor DC fan motor malfunction
Indoor Display E14
Method of
Method of The rotation speed detected by the Hall IC during fan motor operation is used to determine
Method of
Malfunction
Malfunction abnormal fan motor operation
Malfunction
Detection
Detection
Detection
Malfunction
Malfunction Decision
When the detected rotation feedback signal don't received in 2 minutes
D Conditions c e s i o i n
Detection
Conditions
Conditions
Causes Operation halt due to breaking of wire inside the fan motor.
Supposed
Fan motor overheat protection
Supposed
Causes
Operation halt due to breaking of the fan motor lead wires
Detection error due to faulty indoor unit PCB
* Caution Be sure to turn off power switch before connect or disconnect connector,
Troubleshooting
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
or else parts damage may be occurred.
Yes
Yes
Yes
No
No
Pull out the terminals on the indoor
No
mainboard and reinsert them.
Measure whether there is voltage pulse(0-5VDC)
between the positions middle wire and black wire
Yes
of Terminal CN2 on the indoor PCB
Is it ok?
the indoor pcb is damaged and need replace
17
Service diagnosis
No
Yes
Yes
Domestic air conditioner