Error Code F5
Freezer failed to complete defrost cycle within 150 minutes
Critical
Stop using immediately - risk of damage or safety issue
Also displayed as: F5 (F-ROOM STEP 5 LED blinking)
What This Means
Separation of housing related to F Compartment Defrost Heater; Contact error or disconnection of heater wiring; Short circuit in defrost heater circuit; Thermal fuse blown (110°C cutout); Bimetal defect (stuck open or closed); Defrost heater element failure (open circuit)
What actually causes this:
Blown thermal fuse, failed bimetal, open defrost heater element, or PCB relay defect
First Thing to Check
Measure resistance between CN72 #5 and CN73 #1; should be approximately 260 ohm
Parts Involved
How to Fix
- 1
Run Self-Diagnosis function before powering off unit
- 2
Check resistance between MAIN PCB CN72 #5 and CN73 #1 (should be 260 ohm ± 10%)
- 3
0 ohm = short circuit in heater; infinite ohm = open (blown thermal fuse, failed bimetal, or open heater)
- 4
Check voltage between CN30 pin 4 and pin 5 for F-DEF sensor status
- 5
Check bimetal continuity (open at room temp = failed bimetal)
- 6
Check thermal fuse continuity (one-shot device, 110°C)
- 7
Verify defrost relay on PCB operates
- 8
For forced defrost test: press Power Cool + Fridge simultaneously 6 sec, press Fridge to enter Test Mode, press button twice
This Error Applies To
Samsung RT21M6215 Series Refrigerators (2017) (2017–present)
Related Error Codes
Freezer compartment air temperature sensor is open or shorted
Refrigerator compartment air temperature sensor is open or shorted
Freezer compartment fan motor is not spinning or feedback signal lost
Freezer defrost sensor open or short circuit
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Ambient temperature sensor is open or shorted
Condenser fan motor is not operating or feedback signal lost
Compressor has failed and stopped operating