It is most likley the thermostat which is located inside the drum where you load your clothes, all you need to do is open the door and run your hand round the door section on the inside and you will feel the top of the thermostat. You will need to get your head inside the drum and look up to see the thermostat. It is held in position with two phillips head screws and cost £12.oo in the UK
Dave- N ireland, June 2007