The F09 indicates that the control board detects an overflow condition due to the flood contact on the pressure switch being closed. If the washer is empty, then the pressure switch likely has a stuck overflow contact. Sometimes, you can free up this stuck contact by tapping on the pressure switch with the handle of a screwdriver. To access the pressure switch, unplug the washer and remove the top panel. Three screws on the back of the top panel secure it to the washer cabinet. Remove these screws and then pull the panel back and up to remove it from the washer. The pressure switch is illustrated as key 23 in the image below. If tapping the pressure switch does not release the stuck contact, then this component will need to be replaced. The part number is 8181695. You can order this part from the Sears PartsDirect website
If the washer is still full of water, then you could have a drain pump problem or a different failure. Resubmit your question with additional details if you need more help.