GE Profile PSF26PGWBB Technical Service Manual page 54

MAIN CONTROL BOARD TROUBLESHOOTING
The main control board is located at the back of the refrigerator, above the machine compartment on the
right-hand side. (See
Control Board Connector Locator
CONNECTOR PIN INPUT OUTPUT
J1 1 VDC
J1 2 VDC
J1 3 VDC
J1 4 VDC
J1 5
J1 6
J1 7
J1 8
J1 9
.)
CONTROL BOARD PIN DEFINITIONS
Feedback of fresh food evaporator thermistor value. Thermistor
value is NTC (when temperature drops, resistance value increases),
causing return voltage reduction. This value is used to cycle fresh
food evaporator fan, compressor, and condenser fan. Feedback is
fi ltered to respond to 8 degrees of change per minute.
Feedback of fresh food thermistor value. Thermistor value is NTC
(when temperature drops, resistance value increases), causing
return voltage reduction. This value is used to cycle fresh food
evaporator fan, compressor, and condenser fan. Feedback is
fi ltered to respond to 8 degrees of change per minute.
Feedback of freezer thermistor value. Thermistor value is NTC
(when temperature drops, resistance value increases), causing
return voltage reduction. This value is used to cycle freezer
evaporator fan, compressor, and condenser fan, and will not cycle
fresh food fan. Feedback is fi ltered to respond to 8 degrees of
change per minute.
Feedback of freezer evaporator thermistor value. Thermistor value
is NTC (when temperature drops, resistance value increases),
causing return voltage reduction. This thermistor value is used
to cycle the defrost heater on during defrost when temperature
is below defrost value and off when the temperature is above
defrost value. This value is also read during power-up to determine
if refrigerator goes into pulldown mode or cycle continuation.
Feedback is unfi ltered and responds immediately.
VDC Provides 5 VDC for thermistors.
VDC Model Selector.
VDC Model Selector.
VDC Model Selector.
VDC Model Selector.
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FUNCTION
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