LG · Refrigerator

Er FS

Freezer Sensor Error

Severity

High

When a LG Refrigerator shows Er FS on its display, the internal diagnostic system has flagged a condition known as "Freezer Sensor Error". Most repairs for this code are straightforward and can be completed at home.

Owner's Summary

Your LG refrigerator's freezer temperature sensor has failed, meaning the control board can't accurately monitor freezer temperature. This can cause inconsistent freezing or excessive compressor running. Replacing the sensor is a relatively affordable fix.

Symptoms

LG refrigerator freezer not maintaining temperature, Er FS error code

Common Causes

Faulty freezer temperature sensor
Sensor wiring fault or disconnection
Sensor connector corrosion
Control board not reading sensor correctly

How to Fix

1 Locate the freezer sensor, typically mounted near the evaporator coil
2 Test sensor resistance and compare to LG's specification chart
3 Inspect and clean sensor connector
4 Replace sensor if resistance is out of range
5 Replace control board if sensor and wiring test good

Tools You'll Need

Multimeter Electrical Contact Cleaner Flashlight

Most of these fixes need only basic hand tools. If your repair requires opening electrical housings or testing live components, a multimeter and basic electrical safety knowledge are essential — when in doubt, call a technician.

Technical Explanation

The freezer sensor provides critical feedback for compressor cycling and defrost timing logic. Er FS is generated when sensor resistance falls outside the valid temperature-resistance curve, causing the control board to lose reliable temperature feedback for the freezer compartment.

Is It Safe to Keep Using?

Food safety concern if freezer temperature is compromised — check frozen food condition and consider a backup freezer while diagnosing.

Technician's Pro Tip

Always test the sensor with the refrigerator unplugged using a multimeter set to resistance (ohms). A reading of infinite resistance (open circuit) or near-zero (short) confirms sensor failure rather than a software glitch.

Related Codes

OE — LG Washing Machine

Drain Error — Outlet Error

High

IE — LG Washing Machine

Inlet Error — Water Not Filling

High

LE — LG Washing Machine

Motor Error — Locked Motor

High

Frequently Asked Questions

What does error code Er FS mean on a LG Refrigerator?

Code Er FS on a LG Refrigerator indicates "Freezer Sensor Error." In practice, the most common trigger is faulty freezer temperature sensor. Severity is rated high, and typical repair costs range from $20 to $200.

Can I fix Er FS myself, or do I need a technician?

Many cases of Er FS can be resolved without a technician. The first step to try: locate the freezer sensor, typically mounted near the evaporator coil. If that doesn't clear the code, work through the remaining steps in the "How to Fix" section above before assuming a part needs replacing.

Is it safe to keep using my refrigerator with code Er FS showing?

Food safety concern if freezer temperature is compromised — check frozen food condition and consider a backup freezer while diagnosing.

How much does it cost to repair Er FS on a LG Refrigerator?

Repair costs for code Er FS typically range from $20 to $200. Freezer sensor: $20–$60; Control board: $100–$200. Costs on the low end usually reflect a DIY fix with no parts required, while the high end reflects a part replacement plus professional labor.

Estimated Repair Cost USD

$20 – $200

Freezer sensor: $20–$60; Control board: $100–$200