Open the washer door and inspect the drum for any items that may be preventing the door from closing properly. Remove items if the washer is overloaded.
Close the door firmly so that the door switch engages. If the door is not closed completely, the lock will not turn on.
Unplug the washer, wait one minute and restore power. Select a new wash cycle and press "Start" to begin.
Wait at least three minutes after the start of the wash cycle for the lock to engage.
Contact an authorized service professional if the lock continues to fail.