Hi, my name is Peter.
The LG dryers will flash the clean filter light when ever you push the power button to start a cycle. If the dryer will not start then you have another problem. Does the light in the drum turn on when you open the door?
No it is just a reminder. The dryer will not start?
Does "CL" show on the display. If yes then your dryer is in child lock. Press and hold the "rack dry" button for 3 seconds then your dryer should work. If not in child lock mode then you have a defective display board or loose wire connection at the board since it will not allow commands. Remove the top panel to get to the control panel and check all of the wiring connections. If all good then you have a defective display board.
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