How do I fix error code FREEZER_DEF_SENSOR on a Samsung refrigerators?

1. undefined: Verify voltage at MAIN PCB CN20 pins 6 and 8 is between 1.0V and 4.5V 2. undefined: Measure resistance at F-DEF: CN20 '6' ↔ '8' and compare to DATA1 table 3. undefined: Check for 0Ω (short) or ∞Ω (open)

Samsung Refrigerators2023–present

Error Code FREEZER_DEF_SENSOR

Q: What does error code FREEZER_DEF_SENSOR mean on a Samsung refrigerators?

Freezer defrost sensor is faulty or disconnected Connector CN20 pins 6/8 loose or disconnected; Defrost sensor (502AT) open or shorted; Wiring damaged near evaporator

Freezer defrost sensor is faulty or disconnected

Moderate

Address soon - your appliance may not work properly

Also displayed as: F blinks

What This Means

Connector CN20 pins 6/8 loose or disconnected; Defrost sensor (502AT) open or shorted; Wiring damaged near evaporator

What actually causes this:

The sensor that monitors freezer defrost temperature has failed, which will prevent proper defrost cycle termination and may cause ice buildup on the evaporator.

First Thing to Check

Locate the defrost sensor clipped to the freezer evaporator coil and confirm its wiring connector is firmly attached.

Parts Involved

Thermistor 502AT (F-DEF sensor)MAIN PCB CN20

How to Fix

1
Verify voltage at MAIN PCB CN20 pins 6 and 8 is between 1.0V and 4.5V
2
Measure resistance at F-DEF: CN20 '6' ↔ '8' and compare to DATA1 table
3
Check for 0Ω (short) or ∞Ω (open)

This Error Applies To

Samsung RF23BB89 Series Refrigerators (2023) (2023–present)

Service manual exact match: RF29BB89***Service manual exact match: RF24BB66***Service manual exact match: RF30BB62***Service manual exact match: RF29BB82***Service manual exact match: RF30BB69***Service manual exact match: DRF36C300**Service manual exact match: RF24BB69***Service manual exact match: RF30BB66***+2 more