4-2-7) When Fan Does Not Operate - Samsung RSJ1K Series Service Manual

TROUBLE SHOOTING

4-2-7) When Fan does not operate

For C-FAN
It reads DC8~12V
between MAIN PCB GND
and CN74 #2.
NO
For C-FAN
It repeats DC7~12V,
and DC 2V or lower between MAIN PCB GND
and CN74 PIN #2.
YES
Note
Pulse signals being generated when the motor is rotating are to be input to CN74 #7(F), #6(R) and #5(C).
These will be input to MICOM and when there are no input signals with the motor rotating, the fan will be
turned off and then be turned on in 10 seconds.
If there are still no input signals, it keeps trying the above 4 times. And, if it still fails, it runs the motor in 10
minutes. It is implemented to prevent the motor from being overloaded due to restrictions by foreign
substances such as ice built up around the motor.
For R-FAN
It reads DC8~12V
between MAIN PCB GND
and CN74 #3.
NO
Reading with Door closed.
-.OPEN 5V, CLOSE 0V
For R-RAN
It repeats DC7~12V,
and DC 2V or lower between MAIN PCB GND
and CN74 PIN #3.
YES
74
Start
NO
COMP is Off?
YES
For F-Fan
YES
It reads DC8~12V
between MAIN PCB GND
and CN74 #4.
NO
NO
Freezer/Fridge/Home
Bar Door S/W is closed.
YES
Apply power around 5
minutes after the power off.
Upon the initial power on,
Comp and F/R/C-Fan operate
(To prevent the compressor
for 5 minutes regardless of
from being overloaded)
the conditions.
For F-FAN
NO
It repeats DC7~12V,
and DC 2V or lower between MAIN PCB GND
and CN74 PIN #4.
YES
Possible Causes
1. Defective FAN-MOTOR
2. Contact problem at the terminal
3. Check the motor rotating pulse input upon Fan Motor operation.
(Refer to Fan-Motor Circuit in this manual)
Run Forced Operation
FAN operates normally.
Check after closing the
Door. When there is Door
alarming, repair the Door
S/W connector.
Replace MAIN PCB