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Model reference

LG LFC21755ST

Refrigerator

3 documents18 error codes13 service modes

Available documentation

Service Manual

  • Refrigerator Service Manual46 pg
    Covers this model
  • Refrigerator Service Manual66 pg
    Covers this model
  • Refrigerator Service Manual42 pg
    Covers this model
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Error codes (18)

CodeMeaning
dHDefrost heater or defrost circuit malfunctiondSDefrost sensor defect (short-circuited or open).ErDefect code displayed on refrigerator and freezer display panels when a fault…Er CFAbnormality of BLDC fan motor for condenser (mechanic room); no feedback signal…Er COCommunication error between Micom of Main PWB and Display Micom, caused by poor…Er dHPoor defrosting error; defrosting sensor has not reached above 8°C within 1…Er dSDefrosting sensor error caused by short or disconnection of the defrosting…Er FFAbnormality of BLDC fan motor for freezer; no feedback signal received within…Er FSFreezer sensor error caused by short or disconnection of the freezer sensor.Er HSHumidity sensor error caused by short or disconnection of the humidity sensor.Er ISIcing sensor error caused by short or disconnection of the icing sensor.Er ItIce maker kit defect; other electrical system error such as motor, gear, Hall…Er rSRefrigerator sensor error caused by short or disconnection of the refrigerator…Er rtRoom temperature sensor error caused by short or disconnection of the room…FFFreezer fan motor failure or lock condition detected.FSFreezer sensor defect (short-circuited or open).rFRefrigerator sensor defect (alternate display code for refrigerator sensor…rSRefrigerator sensor defect (short-circuited or open).

Service modes (13)

  • Demonstration (Display) Mode1
  • Error History DisplayPress the Ice Plus button and Freezer button simultaneously.
  • Freezer Fan Variable RPM CheckPress and hold the WARMER keys of both the REF TEMP and FRZ TEMP simultaneously.
  • Icemaker Test ModePress and hold the Fill Key for 3 seconds.
  • LED Check FunctionPress and hold the WARMER key of refrigerator temp and the WARMER key of freezer temp for one…
  • Room Temperature Sensor Check DisplayPress and hold the WARMER key of refrigerator temp and the WARMER key of freezer temp for more than…
  • Temperature Display Mode Change (°F/°C)Press and hold the FRZ TEMP and the COLDER key of REF TEMP keys at the same time for over five…
  • Temperature Mode Change (°F/°C)Press and hold the FRZ TEMP key and the COLDER key of REF TEMP at the same time for over 5 seconds.
  • Test Mode (Main PCB)Press the button on the main PCB controller to enter test mode.
  • Test Mode (PCB and product function check)Press two buttons on the display panel simultaneously (specific combination per test mode). Test…
  • Test Mode 1Push the test button on the Main PCB 1 time
  • Test Mode 2Push the test button on the Main PCB 2 times
  • Test Mode 3 (Forced Defrost)Push the test button on the Main PCB 3 times

Full entry steps, exit procedures, and test sequences are available in Max.

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