In this guide
TL;DR: An LG dryer's Check Filter light at power-on can be a routine lint-screen reminder. A light that appears during a load, a Flow Sense alert or a separate code needs the exact model's instructions. Clean the screen as directed, but do not treat a disappearing reminder as proof that the exhaust is clear.
A light before Start can be a normal reminder
LG's U.S. Check Filter guidance describes a startup reminder that should turn off when Start/Pause is pressed. The light can appear when the screen is already clean. Before another load, check the screen anyway; the reminder going away does not perform that work.
The DLEX8000 and DLGX8001 family manual likewise describes its Check Filter light flashing at power-on and going out when the cycle starts. These are documented examples. Find your model number and compare its display instructions before replacing a filter or assuming a sensor has failed.
A light during drying deserves a different check
LG's DLE5955 and DLG5966 family guide describes two uses for its indicator: a reminder before a load and a warning when the lint filter becomes clogged during drying. That behavior is specific to the models on the guide's cover. Do not dismiss every Check Filter light as a startup notice.
Record when the light appears and what the machine does next. Include the exact letters or icons, whether the drum stops, and whether drying has changed. A phone notification is another place to check the wording: use the model's app help for that notice. A panel-light explanation does not establish an app's counter or reset procedure.
Flow Sense concerns the exhaust path
The DLEX8000/DLGX8001 manual identifies Flow Sense as a warning of restriction in the home's exhaust system. It directs owners to check for a kinked connection and duct buildup, and warns that using the dryer with the light on may be unsafe. Leave it off while the restriction is assessed.
A clean lint screen cannot show what is happening throughout the duct. Our long-drying guide separates load problems from visible exhaust clues. If the route is hidden, damaged, high or inaccessible, or the warning persists after permitted care, arrange the appropriate vent inspection or appliance service. Keep cabinet panels and gas connections intact.
Check the dryer type before applying an exhaust explanation. A true ventless dryer has no outdoor exhaust duct. Its filter and condensate instructions still matter; the ventless tool-fit guide explains why a vent brush is not a heat-exchanger or water-line tool.
Screen care and warning diagnosis are separate jobs
Before physical cleaning, switch the dryer off, unplug it and let hot parts cool. The DLEX8000/DLGX8001 manual calls for rolling loose lint off the screen. A very dirty or fabric-softener-clogged screen may be washed in warm, soapy water, then dried thoroughly. Never operate those dryers with a missing or wet filter. Use the lint-screen care guide with your own model's permitted method.
If the manual permits cleaning a dry, reachable housing area, the GOHALL lint brush and vacuum kit can help collect loose lint there. Confirm the actual vacuum connection and use its complete Method A or Method B assembly; the vacuum-attachment guide covers those connections. Keep the dryer unplugged, use gentle movement and stop at resistance. The kit does not repair a damaged duct, heater, sensor or control, and it cannot confirm that a persistent airflow warning is resolved.
If the dryer will not start or powers off during operation, LG's Check Filter support page calls for service to obtain a diagnosis. Do not keep buying parts, resetting controls or running trial loads solely to make a light disappear.
Question about a recurring startup light
Will replacing the lint screen stop a normal Check Filter reminder?
The documented startup reminder appears when the dryer is powered on, so a new screen is not a remedy for that normal behavior. Replace a screen for damage or incorrect fit according to the model's parts guidance. A different warning or a drying problem needs its own response.