Error code
F3
Meaning
Defrost system cannot monitor freezer coil temperature
Moderate
What to do
Why this happens
Causes may include separation in sensor housing, contact errors at connectors, disconnection of sensor wires, short circuits within the sensor line, or temperature readings exceeding 149°F or falling below -58°F.
How to fix it
Replace the freezer defrost temperature sensor
SourceSamsung service manual