Samsung Refrigerators2017–present

Error Code F3

Freezer compartment air temperature sensor is open or shorted

Critical

Stop using immediately - risk of damage or safety issue

Also displayed as: F3 (F-ROOM STEP 3 LED blinking)

What This Means

Sensor housing separation from evaporator; Contact error at sensor connector; Disconnected sensor wiring harness; Short circuit in sensor or wiring

What actually causes this:

Failed, disconnected, or shorted freezer thermistor or its wiring harness; sensor housing fallen off evaporator

First Thing to Check

Verify CN30 connector is fully seated; measure voltage between CN30 pin 6 and pin 7

Parts Involved

F-Sensor (Freezer Air Thermistor, PX41C chip)Main PCBCN30 Connector

How to Fix

  1. 1

    Check MAIN PCB CN30 connector is properly inserted

  2. 2

    Measure voltage between MAIN PCB CN30 pin 6 and pin 7 (should be 4.5V to 0.5V at normal temps)

  3. 3

    If voltage < 0.6V = short circuit; if voltage > 4.6V = open circuit

  4. 4

    Cross-reference voltage with DATA1 Temperature/Voltage/Resistance table

  5. 5

    Verify IC10 MICOM Pin #52 input voltage matches reading at CN30 #6 to #7

  6. 6

    Check wire connections for damage

  7. 7

    If connector contact defect: reconnect; if sensor failed: replace

This Error Applies To

Samsung RT21M6215 Series Refrigerators (2017) (2017–present)

Service manual exact match: RT18M6213**Service manual exact match: RT18M6***Service manual exact match: RT21M6211**Service manual exact match: RT18M6114**Service manual exact match: RT18M6215**Service manual exact match: RT21M6215**Service manual exact match: RT18M6211**Service manual exact match: RT21M6***

Need more help with your Samsung refrigerators?