6-3. If ICE Room Fan does not operate
6. Self Diagnosis & Trouble Shooting
To do list
Does DC7~12V alternate with
below DC2V between MAIN
PCB Ground J23 JUMMPER
and CN76-"2"(Black)?
FAN works normally
YES
YES
YES
Reference
CN76 “6” will generate the pulse signal
when motor rotates.
These signals will be input into MICOM.
Unless signals are not input during
motor operating, will be ON 10seconds
after fan OFF. But if signals are not still
taken, the above operation will be retried
four times more. If signals are not taken
continuously, the motor will be restarted
after 10 minutes.
This function is against the case that
motor movement would be restrained by
foreign matters like ice.
◆
Predicted Cause
①
FAN-MOTOR troubles itself
②
Bad wiring connections.
③
Wrong Input of the fan motor
rotation pulse
FAN pulse
voltage
CN76-
”6”(Pink)
The voltage is variable due
to pulse signal but
measured about 2~3V with
the Multi-Meter.
PCB Typical
Ground J23
JUMMPER
☞
Checking method of Ice Room FAN Motor Voltage
with the voltage between Ice Room FAN ;
CN76-"1"(Gry) shall be less than DC 7~12V.
- Ice Room FAN Motor Voltage shall be less than
DC 7~12V.
1) Ice Room - FAN
☞
Display for checking the self-
diagnostic function
Ice Room FAN ERROR
PCB Typical Ground
J23 JUMMPER
182