Samsung Refrigerators2016–present

Error Code 4

Freezer defrost sensor has failed or lost connection

Moderate

Address soon - your appliance may not work properly

Also displayed as: LED 4 blink

What This Means

Sensor housing slipped out of connector; Open or shorted wire; Sensor reads temperature out of valid range (+50°C to -50°C)

What actually causes this:

The sensor clipped to the freezer evaporator coil has come loose or its wire has been damaged, so the board cannot tell when the defroster is done.

First Thing to Check

Verify the defrost sensor is clipped properly to the evaporator coil and its connector at CN2 pins 1 and 6 is seated.

Parts Involved

F-Defrost Sensor (THERMISTOR PX-41C)CN2 connector pins #1 and #6

How to Fix

  1. 1

    Access self-diagnostic mode

  2. 2

    Measure voltage at Case Connector CN2 pin #1 to pin #6 — should be between 1.0V and 4.5V

  3. 3

    Inspect sensor placement on freezer evaporator

  4. 4

    Check wiring from sensor to CN2

This Error Applies To

Samsung RS27FDBTNS Series Refrigerators (2016) (2016–present)

Service manual exact match: RS27FDBTNSR/**Service manual exact match: DYF42SBIWSService manual exact match: RS27FDBTNSR/AAService manual exact match: RS757LHQESR/**

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