How do I fix error code EXT - SENSOR on a Samsung refrigerators?

1. undefined: 1. Check and reconnect MAIN PCB SENSOR connector CN31 2. undefined: 2. Measure voltage between CN31-'1'(WHT) and CN31-'2'(WHT) terminals 3. undefined: 3. Voltage should be between 4.6V and 0.5V 4. undefined: 4. Input voltage at IC10 MICOM Pin #21 should be normal 5. undefined: 5. Check sensor resistance - should indicate normal ambient temperature (typically 4-20 kΩ range) 6. undefined: 6. Verify sensor assembly is properly installed

Samsung Refrigerators

Error Code EXT - SENSOR

The external temperature sensor isn't sending correct readings

Moderate

Address soon - your appliance may not work properly

Also displayed as: Freezer -21°C LED LAMP

What This Means

Connector slipped out or open contact; Wire cut or short-circuited; Temperature sensor defective or reading out of range; Sensor wires damaged; MAIN PCB connector CN31 not seated properly

What actually causes this:

The ambient temperature sensor wire came loose or the sensor failed

First Thing to Check

Turn off the refrigerator and visually check if the sensor connector is fully plugged in

Parts Involved

External Temperature SensorMAIN PCB CN31 ConnectorWire HarnessMAIN PCB

How to Fix

1
1. Check and reconnect MAIN PCB SENSOR connector CN31
2
2. Measure voltage between CN31-'1'(WHT) and CN31-'2'(WHT) terminals
3
3. Voltage should be between 4.6V and 0.5V
4
4. Input voltage at IC10 MICOM Pin #21 should be normal
5
5. Check sensor resistance - should indicate normal ambient temperature (typically 4-20 kΩ range)
6
6. Verify sensor assembly is properly installed