Samsung RF18A Series Service Manual page 90

CHECK THE INSTALLATION STATUS
IF FAN does not operate
F FAN pulse voltage CN51 "15"(PNK)
The voltage measured
around 2~3V with multi-
meter though the voltage is
very weak because of pulse
signal.
☞ Display for checking the self-diagnostic
function
F FAN C FAN
ERROR ERROR
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Reference
CN51-15(F),CN51-16(R),CN51-21(C) will generate thepulse signal when motor rotates.These
signals will be inputted into MICOM.
Unless signals are not inputted during motor operating, will be ON 10 seconds after fan Off.
But if signals are not still entered, the above operation will restart four times more.
If signals are not entered continuously, the motor will be restarted after 10 Minutes. This
function is effective when the normal operation of motor would be restrained by foreign
matters such as ice.
The voltage between PCB typical Ground CN51 "13" Pin and
F FAN : CN51 "17" (S/BLU) shall be less than DC 7~12V.
R FAN : CN51 "18" (BRN) shall be less than DC 7~12V.
C FAN : CN 51 "23" (PRP) shall be less than DC 7~12V.
- Recheck if resistance values are different after measuring.
R FAN
ERROR
90
PIN Number