I also have the same machine.
The normal cause is that the machine thinks it's not completely empty.
The pressure sensor (that detects how full the machine is) is connected via a pipe to a grommet on the lower rear of the drum housing.
This gets clogged with soap gunk.
Remove the pipe and then carefully remove the grommet.
Clean the grommet and pipe in warm water.
Replace the grommet being careful to not push it into the drum.
When this happen to my machine it took a few spin cycles to 'reset' for some reason.
Watch out for the 'door latch' fault on these machines. This latch is directly under the detergent tray and if this is blocked then water can find its way into the latch blowing this and the controller.
(Just fixed mine on Saturday)
Ian
January 2010