I had the same problem. Sears came out to fix mine. It is your locking mechanism. If you seerust at the back hinges of you washer lid the the wires in the locking mechanism are alsorusted. First they came out and scraped the wires and metal parts inside the locks. It workedfor 6 months. Then they could not scrap them anymore because they got to thin and broke, sothey ordered new locks. The main lock facing your left of the washer is the one with a magnet and controls the other one on the other side. The part number is 6 2902540 or Ark-Les11500-61. You can order it from sears but is is almost $200 part. If you take out a sears agreement for $200 they will fix both locks and guarantee it for a year. That is how I got minerepaired.
