Try relacing the door interlock straight off. Cheap part.
Spares suppliers:
www.4directelectricals.co.uk
http://www.ukwhitegoods.co.uk
www.ukapplianceparts.com
http://www.domesticspares.co.uk
http://shop.ezee-fix.co.uk
http://www.espares.co.uk
or simply go into google and type in "washing machine spare parts" - selecting "pages from uk".
Typical interlock replacement: Power off, remove mains plug. Remove the plastic band that holds the rubber door seal to the front cabinet. Un-hook the rubber gasket from cabinet lip on the door lock side. Put your hand in and hold the door lock whilst removing the 2 screws you can see from the front. There might be a pressure pipe attached to the lock, if so, just pull it off. Make a note of and disconnect wiring. Refitting is, as they say, a reversal of the above process.
Repair and service your own washing machine. Go to www.2ndwave.co.uk/manual.html
dannyboy, December 2008