I had something similar. Assuming it's a fully built in d/w with just 4 buttons, the on/off button on the rh side has to be held down for at least 6-7 seconds so that it resets. When it's done this you can then select the pre-wash (the one with the spray icon). This runs for about 10 mins and will give out the normal 4 short beeps followed by a long one to say the cycle has finished. If there is no or little water in the bottom of the machine and you heard the drain pump going, you know at least that water is being drained away.
Next try a wash cycle to see if water is being heated and enough spray as opposed to a drible of water is coming through - and thats' where I'm up to trying to find out why not much water is coming through.
Hope that helps a little.
brush-head
March 2008