Error code · Refrigerator

LG Refrigerator Code FU: Cycle Error

Medium · inspection needed

Code: FU
Appliance: Refrigerator
Brand: LG
Warranty: 30-day workmanship

What FU means

FU is the Cycle Error on LG refrigerators with an LED or LCD temperature display. It reports a freezer-compartment problem: 10 minutes after the cooling cycle starts the freezer is still not below 3.5 C, or it climbs above 3.5 C during operation. In plain terms, the freezer is not cooling the way it should. The owner sees FU, and the freezer may feel soft or warm, with the refrigerator side following.

Common causes of FU

Freezer cooling cycle not pulling the temperature down
Blocked vents or a door that does not seal
Sensor reading against the actual temperature

✓ One safe check you can try

1. Unplug the refrigerator for 60 seconds, then plug it directly into a wall outlet. 2. Check the temperature setting is not at its warmest. 3. Cut down how often the doors are opened. 4. Look for blocked vents inside, and clear them. 5. Check the door seals for gaps.

! Why to stop there

If FU returns, the cooling cycle itself needs testing, and a reset cannot show why it is slow.
We check the sensor, the fan, and the cooling performance and quote in writing first.
Some panels also show a Cycle Error light pattern.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

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Other Refrigerator codes

ttLG Refrigerator Code tt: Water Tank Not Detected iTLG Refrigerator Code iT: Ice Maker Motor OdLG Refrigerator Code Od: Wi-Fi Module Link OFFMessage "OFF" on LG Refrigerators r2LG Refrigerator Code r2: Lower Compartment Sensor rFLG Refrigerator Code rF: Fresh-Food Fan Motor rSLG Refrigerator Code rS: Upper Sensor Open or Shorted rTLG Refrigerator Code rT: Room Temperature Sensor

FUFU questions

Why plug into a direct outlet?

An extension cord or power strip can starve the refrigerator of steady power. Use the wall outlet so the reset is a fair test of whether the cooling cycle recovers on its own.

Does FU mean the compressor failed?

Not necessarily. It means the freezer is not cooling on time. The cause may be airflow, a door seal, a sensor, or the cooling system itself, and we test those in order.

Is my food safe with FU?

Check the freezer temperature with a thermometer. If it is rising toward freezing, move items to a cooler and call us so we can find out why the freezer is not cooling.

Book a visit

Still seeing FU?

A technician diagnoses it on site and gives you the price in writing before any work starts.

(713) 597-5662