The F35 indicates that the main control board detects a problem with the analog pressure sensor (water level pressure switch) in the washer. This component senses and controls water level in the washer. This failure could be caused by a pinched or broken air hose between the air trap at the bottom of the washer tub and the analog pressure sensor. It can also be caused by a clogged air trap or a failed analog pressure sensor. If you are able to unplug the washer and pull off the top panel, you can check for the probable cause of this failure. To remove the top panel, remove the screws on the very back of the panel that secure it to the washer cabinet. Pull the top panel back slightly and then and off of the washer. The analog pressure sensor is shown in the second image below. You can see the location of this component in the first image. It is on the side wall just behind the expansion control board. You can check the air pressure hose connection and the wire harness connection on this component. If you find no problems, then you will likely need to replace the component.
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