Error Code F_DEF_SENSOR
Freezer defrost sensor reading error prevents defrost cycle monitoring
Critical
Stop using immediately - risk of damage or safety issue
Also displayed as: F-DEF Sensor Error
What This Means
Bad connector contact at CN20 pin 6 and 8; Open circuit in sensor (infinite resistance); Short circuit in sensor (zero resistance); Water infiltration or corrosion; Bimetal switch failure
What actually causes this:
The defrost sensor lost connection or failed, so defrost cycles cannot be properly monitored and controlled
First Thing to Check
Verify CN20 connector is fully seated and inspect for moisture
Parts Involved
How to Fix
- 1
Check CN20 connector insertion
- 2
Measure voltage between CN20 pins 6 and 8 (BLU and W/GRY)
- 3
Measure resistance between same pins
- 4
Verify against temperature table DATA1
- 5
Check bimetal switch condition
Other Error Codes for RF28T5021S9
Refrigerator compartment temperature sensor is disconnected or dead
Internal humidity sensor has failed or is disconnected
Defrost sensor on freezer evaporator is failed or disconnected
Freezer fan motor is not running or not sending feedback
Supply voltage to compressor is too high
Freezer temperature sensor is failing or disconnected
Ice maker temperature sensor in freezer is failed or unplugged
External room temperature sensor is failed or disconnected