Error Code 4
Freezer defrost sensor has failed or lost connection
Critical
Stop using immediately - risk of damage or safety issue
Also displayed as: Error 4
What This Means
Defrost thermistor open or shorted; Connector CN31-3 or CN31-4 loose; Wiring damage near freezer evaporator; Ice formation damaging sensor leads
What actually causes this:
The sensor that stops the defrost heater when the evaporator is warm enough has failed, which can cause over-defrosting or ice buildup.
First Thing to Check
Inspect the sensor located on the freezer evaporator coil for ice damage or disconnected wire leads.
Parts Involved
How to Fix
- 1
Check voltage at MAIN PCB CN31-3 to CN31-4: should be between 1.0V and 4.5V
- 2
Disconnect CN31 and measure resistance at pins 3 and 4
- 3
At 77°F (25°C), normal resistance is 5.0 kΩ
- 4
Check MICOM IC01 pin #6 voltage (R313 on PCB)
Other Error Codes for RF23M8590SR
Humidity sensor in the fridge compartment has failed
Ice bucket compartment heater has an open or short circuit
Mid drawer damper heater has an open or short circuit
Auto-fill water tank has detected an overflow
Refrigerator defrost sensor has failed or disconnected
Freezer temperature sensor has failed or lost connection
Ambient room temperature sensor has failed
Refrigerator compartment temperature sensor has failed or disconnected