Error code · Dryer

LG Dryer Code FO: Filter Not Inserted

Low risk · DIY check OK

Code: FO
Appliance: Dryer
Brand: LG
Warranty: 30-day workmanship

What FO means

On LG electric, gas, heat-pump, and steam dryers, FO appears when the dryer does not detect the lint filter as properly inserted. Some models flash an insert-filter message instead of, or along with, FO. The dryer stops and will not run a cycle while the filter is missing or crooked. It is a protective stop, because running without a filter pushes lint into the vent and heating area.

Common causes of FO

A lint filter that is missing or not fully seated
Lint blocking the filter slot
A filter-position sensor that is not reading the filter

✓ One safe check you can try

1. Open the door and pull the lint filter out. 2. Remove the lint from the screen, then push the filter back in until it clicks into place. 3. Close the door and press start again. 4. If the filter frame is cracked, replace it before the next load.

! Why to stop there

If FO persists with a seated filter, the sensor that detects the filter needs a test.
A cracked filter frame or lost magnet can also keep the dryer from seeing the filter, and we inspect for that.

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 Dryer codes

nE, nF, nCLG Dryer Codes nE, nF, nC: Wi-Fi and NFC nPLG Electric Dryer Code nP: No Heater Current PFLG Dryer Code PF: Power Failure PSLG Electric Dryer Code PS: Voltage Error tE1, tE2, tE3, tE4, tE5, tE6LG Dryer Codes tE1 to tE6: Thermistor Wrinkle CareLG Dryer Message "Wrinkle Care": End-of-Cycle Tumbling LE1LG Dryer Code LE1: Drum Motor LE2, AE, CE1LG Dryer Code LE2, AE, CE1: Compressor

FOFO questions

What does FO mean on my LG dryer?

FO stands for Filter Out. The dryer cannot tell the lint filter is in place, so it stops the cycle until you reinsert it. A quick reseat of the filter clears it in most cases.

Is it letter O or zero?

The newer LG list uses the letter O, while an older list writes it with a zero. Either way the fix is the same: reseat the lint filter. A letter O and a zero look alike on many displays.

Can I run the dryer without the filter?

No. Lint would travel into the vent and heating area, and that is a fire hazard. Replace a damaged or missing filter before drying again. A cracked frame can also keep the dryer from seeing it.

Book a visit

Still unsure about FO?

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

(713) 597-5662