Error Code 4E
Freezer defrost sensor failed; defrost may not complete
Moderate
Address soon - your appliance may not work properly
Also displayed as: 4E
What This Means
Connector separated from defrost sensor; Wire cut or short-circuited; Defective defrost thermistor
What actually causes this:
Defrost sensor wire has broken or the connector has corroded, usually found near the evaporator where moisture cycles cause deterioration.
First Thing to Check
Inspect the defrost sensor connector at the evaporator area — look for moisture damage or a loose pin.
Parts Involved
How to Fix
- 1
Measure voltage at Main PCB CN30 pins 2 and 8 — should be 1.0V to 4.5V
- 2
Check sensor check point #2 on Main PCB
- 3
Also verify that defrost heater circuit is intact (CN70 pin 7 to pin 1)
This Error Applies To
Samsung RF34H9950S Series Refrigerators (2018) (2018–present)
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