LG Refrigerator Error Codes — Complete Guide

LG refrigerators are everywhere on my route — French door, side-by-side, top-freezer, you name it. They're well-built machines but they throw error codes that can stop you cold if you don't know the system. I've put this guide together from years of field experience so you have a single reliable reference you can actually use on the job.

LG uses a consistent error code system across most of its modern refrigerator lineup, which is a plus. Once you learn the patterns, you'll recognize codes across models fast. I've noted where codes differ between model families.

Before you do anything else: always check for a recent power outage or voltage event. LG boards are more sensitive to power fluctuations than most. A clean power cycle — unplug for 5 minutes, plug back in — clears phantom codes on LG more reliably than on Samsung or Whirlpool. Try it first. If the code comes back, you've got a real problem.

How to Access LG Refrigerator Diagnostic Mode

Most LG French door and side-by-side models have a hidden diagnostic mode that shows stored error codes and lets you run component tests. Here's how to access it on most models:

1. Make sure the fridge is plugged in and powered on.
2. Press and hold the Freezer Temp and Refrigerator Temp buttons simultaneously for about 5 seconds until you hear a chime.
3. The display will cycle through stored error codes. Write them all down before exiting.
4. To exit, press any button or wait 30 seconds.

Sensor Error Codes

Er FF — Freezer Fan Error

The freezer evaporator fan motor isn't running or isn't being detected by the control board. This is one of the most common LG codes I see in the field. First step: defrost the unit completely. Ice buildup around the fan blade is the #1 cause — the motor is usually fine. A full manual defrost (unplug, leave doors open 24–48 hours with towels on the floor) resolves it more often than not.

If the code returns within a week after defrost, your defrost system isn't working. Check the defrost heater and defrost thermostat (see Er dH below). If defrost checks out and the fan still won't spin freely by hand, replace the motor. Part: EAU61524007 or model equivalent.

Er rF — Refrigerator Fan Error

Same as Er FF but for the fresh food section fan. Less common than the freezer fan issue, but same diagnostic approach — defrost first, then check the motor. On French door models, this fan sits behind the rear wall of the fresh food section.

Er CF — Condenser Fan Error

The condenser fan at the bottom rear of the fridge isn't running. Pull the fridge away from the wall and check if the fan area is clogged with dust, pet hair, or debris. A clogged condenser fan is a textbook cause of "fridge isn't cooling" calls that homeowners have been sitting on for weeks. Clean it out first. If the fan area is clear and the fan still won't spin, replace the motor. Part: EAU36519303 or equivalent.

Er FS / Er rS — Freezer or Fridge Sensor Error

The temperature thermistor in the freezer (Er FS) or fresh food (Er rS) section has failed. Test the sensor with a multimeter — at room temperature it should read approximately 5k ohms. Out of range means replace it. These are usually inexpensive parts and a straightforward swap. Parts typically run $15–$35 and take 20–30 minutes to replace.

Er IS — Ice Maker Sensor Error

The ice maker temperature sensor has failed. Check the sensor wiring harness for damage first. If the harness is intact, replace the sensor. On some models this is integrated into the ice maker assembly and requires replacing the whole unit.

Er dS — Defrost Sensor Error

The defrost thermistor has failed. This sensor monitors the evaporator temperature during the defrost cycle and tells the board when to stop heating. A failed defrost sensor typically causes one of two problems: the unit never defrosts (ice builds up on the back wall) or it defrosts too long (water leaks into the fridge compartment or the floor). Replace the defrost thermistor and inspect the bi-metal thermostat while you're in there.

Defrost System Error Codes

Er dH — Defrost Heater Error

The defrost heater circuit has an open circuit. This is the most common root cause behind Er FF on LG units — the heater fails, ice builds up, and eventually blocks the fan. Test the defrost heater for continuity. No continuity = open heater, replace it. Also test the bi-metal thermostat in series with the heater — it's a thermal fuse that opens at a set temperature and often fails alongside the heater on older units.

Er CO — Communication Error

The main control board and one of the sub-boards (display board, ice maker board, or linear compressor inverter board) have lost communication. Check all wiring harness connections first — on LG French door units, the door wiring harnesses run through the hinges and take wear over time. If all connections are tight and the code persists, identify which sub-board is failing by swapping if you have a spare, or use a multimeter to test continuity on the communication lines.

Er 1F / Er 2F — Ice Maker Errors

Er 1F indicates the ice maker fan isn't running. Er 2F is a general ice maker malfunction code. For Er 1F, check the ice maker fan motor directly. For Er 2F, run through the ice maker systematically: water supply valve, fill tube for freezing, ice maker motor, and temperature sensor. LG ice makers on French door models have a higher-than-average failure rate — if the unit is out of warranty and the ice maker has already been serviced once, a full ice maker assembly replacement is often the right call.

Compressor & Sealed System Error Codes

Er gF — Gas (Refrigerant) Leak Suspected

The control board has detected a pattern of behavior suggesting a refrigerant leak — compressor running excessively, poor temperature recovery, or sensor readings consistent with low charge. This code alone doesn't confirm a leak; it's a flag. Pull out your leak detector and check the usual suspects: the evaporator coil, service ports, and any repaired areas. If you find a leak, this is a sealed system repair requiring EPA 608 certification. Quote appropriately — on LG linear compressor units especially, repair-vs-replace math often favors replacement if the unit is over 7 years old.

Er 1C / Er 5C — Compressor Inverter Error

The linear compressor inverter board has failed. LG linear compressors use a variable-speed inverter rather than a traditional start relay/overload setup. When the inverter board fails, the compressor can't start. Part: the inverter board is typically mounted at the rear bottom of the unit near the compressor. Before replacing, verify power is reaching the board and that the compressor windings test within spec (usually 7–11 ohms across each terminal). A failed compressor will read open on one or more windings.

Water & Ice System Error Codes

Er IF — Ice Full / Ice Maker Off

Not actually an error — the ice bin is full and the ice maker has paused. Verify the ice bin is seated correctly. If the bin is empty and the code still shows, the ice level sensor (feeler arm or infrared sensor depending on model) has failed or is stuck in the "full" position. On infrared sensor models, clean the sensor eyes with a dry cloth — frost or condensation buildup is a common false trigger.

Er 22 — Water Inlet Valve Issue

The control board isn't detecting water flow when the inlet valve is commanded to open. Check the household water supply valve behind the fridge first. If supply is good, test the inlet valve solenoid coils with a multimeter — each coil should read 200–500 ohms. Out of range or open = replace the valve. Also check the water supply line for kinking or freezing at the back of the fridge.

Display & Control Board Error Codes

Er 5 — EEPROM Error

The main control board's internal memory (EEPROM) has failed or corrupted. Try a full power cycle first (unplug 10 minutes). If the error persists, the main PCB needs replacement. This is not a common code but when it appears, the board is the answer.

Er 6 — Display Board Communication

The main board and display board can't communicate. Check the ribbon cable or wire harness between them. On models where the display is on the door, the hinge wiring is the first place to look. If the harness is intact, one of the two boards has failed — start with the display board (usually cheaper) before the main PCB.

LG Error Code Quick Reference Table

LG Linear Compressor — What Every Tech Needs to Know

LG introduced linear compressors on most of their French door models starting around 2013. They're quieter and more efficient than traditional compressors, but they have a well-documented failure rate that's created a steady stream of work for appliance techs nationwide.

Here's what you need to know going into an LG linear compressor job:

• Check the service bulletin first. LG has issued multiple extended warranty programs. The compressor may be covered even if the unit is out of standard warranty.
• Test the compressor windings. Disconnect the compressor and test resistance across all three terminals. On a healthy LG linear compressor you should see consistent readings (typically 7–11 ohms). An open reading on any terminal means the compressor has failed internally.
• Don't skip the inverter board. A failed inverter board presents the same symptoms as a dead compressor. Test the board first — it's cheaper to replace and much faster. Part numbers vary by model; pull the model number from the inner door sticker.
• Quote carefully. Compressor + refrigerant recovery + recharge + labor on an LG French door can hit $600–$1,000. On a unit over 7–8 years old, the math often favors replacement. Be honest with your customer. They'll remember that.

When to Call a Professional

For homeowners: sealed system work (Er gF, Er 1C/5C, compressor codes) is not DIY territory. These require EPA 608 certification, refrigerant recovery equipment, and proper evacuation and recharge procedures. Getting this wrong can damage the unit permanently and void any remaining warranty.

Fan errors and sensor replacements are more approachable if you're handy, but pulling panels and tracing wiring on LG French door models takes experience. If you're not comfortable, call a tech — a $150 service call is a lot cheaper than a misdiagnosis.

For techs: If you want LG error codes, part numbers, and diagnostic steps without leaving your job management screen, ApplianceOps AI Diagnosis Assist has you covered for LG and every other major brand. It's built into the dispatch screen — enter model and code, get the answer.

Part numbers may vary by model. Always verify against the model-specific parts diagram. Check lg.com/us/support for active service bulletins before quoting compressor repairs.