Error code
R - SENSOR
Meaning
The refrigerator temperature sensor isn't reading correctly
Moderate
What to do
Why this happens
Potential causes include an open or slipped-out connector, a wire that is cut or short-circuited, a defective refrigerator temperature sensor with abnormal readings, or an improperly seated MAIN PCB connector CN30.
How to fix it
This one needs a professional technician
SourceSamsung service manual