What does EC 20 mean?
Refrigerator evaporator temperature sensor is reading out of range.
Common causes
- Failed evaporator thermistor
- Loose sensor connector
- Damaged wiring
- Frost buildup on sensor
Diagnostic & testing steps
- 1. Access evaporator cover inside refrigerator compartment
- 2. Locate thermistor on evaporator coil
- 3. Check connector is fully seated
- 4. Measure resistance: ~7K-10K ohms at 38°F
- 5. Replace sensor if readings are erratic or out of range
Tools required
- Multimeter
- Phillips screwdriver
- Torx screwdriver
OEM parts & part numbers
Evaporator Temperature Sensor
Part numbers: 4204380, 4204381
Safety warning
⚠️ Unplug before accessing evaporator area
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