Presume you have already purchased a new door catch (easily obtainable onlIne). First unplug your machine. Open the dishwasher door all the way to horizontal. Using a phillips screwdriver take out the four screws on the inside top of the door and also the first screw on each side going down the door. You will now be able to prise the panel containing the door catch towards you if door is horizontal and be able to see and undo the two phillips screws securing the catch. Gently pull off the two wires from the old switch (noting which connector they attach to). Then simply reassemble everything In reverse order. Took me six minutes.
Jack, March 2009