How can I fix my Baumatic BDW13 Dishwasher?

My dishwasher has developed a mind of it's own and wont work properly on any setting. Sometimes it goes through the whole cycle but without getting hot, other times it starts up, runs for three or four minutes then makes the beeping sound to say the program has ended and stops without actually washing anything. I called an engineer who said it needs a new control module at £220! and being a special order part he could not get it before Christmas. Any ideas anyone?