If you have water setting off the flood switch, I would suspect one or both of the actuators are not closing the lid and the ratcheting sound would further raise my suspicions. You can test the actuators with the drawers out just to verify their operation by using the tech sheet behind the lower drawer. Also, if the actuators are white in color, they are the old style and should to be replaced with the newer black versions (the part number should sub to the new version). Water left after the wash is usually related to either a damaged fin on the rotor portion of the motor (the part inside you can remove) or the installation of the drain line. These require a very specific installation and any deviation will result in poor draining during the wash cycles.