Error Code 4
Freezer defrost cycle sensor is not working
Moderate
Address soon - your appliance may not work properly
Also displayed as: 4
What This Means
Thermistor disconnected or loose connector; Thermistor defective or shorted; Main PCB connector failure; Wiring harness damage between sensor and Main PCB
What actually causes this:
The defrost sensor connection loosened or the sensor itself failed
First Thing to Check
Check the connector behind the refrigerator near the defrost components
Parts Involved
How to Fix
- 1
1. Check Main PCB CN30-5 to CN76-1 voltage — normal range: 4.5V to 1.0V
- 2
2. Reconnect thermistor connector if loose
- 3
3. Measure thermistor resistance: 5.0 kΩ at 77°F (25°C)
- 4
4. Replace thermistor if open or shorted
This Error Applies To
Samsung RF22NP Series Refrigerators (2018) (2018–present)
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