Product review (5 stars): Whirlpool 35 Error and sud error
I had the 35 error and the sud error.  After browsing I found this was the recommended fix.  Three hex head screws on the back of the washer by the top(use a small socket) and the top cover slides back a few inches and lifts up.  This switch is located in the right rear corner.  It is an easy install. Only trick is to rotate the switch 90 degrees and it will come loose from the sidewall.  There is one electrical jack that will wiggle off, and one rubber hose.  Remove and replace.  Whole thing took ten minutes.  Btw, you do not need to move your washer.