It sounds like you have a blockage. First of all if your drain hose is connected to the u bend in your sink pull the pipe off & remove the spout, check for any blockages there. If this is ok then tilt your appliance back approx. 45 degrees & rest the back on a wall or something equally sturdy, using a flat bladed screwdriver prise the plastic kick strip at the bottom, front of the appliance away from the cabinet (it is secured by clips left, middle & right hand side). Once this is off the pump filter cap will be revealed on the right hand side, place a washing up bowl or other shallow container on the floor, directly underneath this cap. Turn the cap & drain the water out, when the water stops remove the cap all the way & remove any foreign objects, make sure to check inside the housing that nothing is stopping the impellor inside from turning. Once done re-assemble & check the pump works before filling with water by selecting pump out only on your program selector.
If it still fails to pump out then there will be a blockage in the black pipe on the bottom of the drum. Tilt the appliance back again & remove the jubilee clip securing the pipe to the bottom of the drum, remove the pipe & check for blockages, when you refit the pipe take extra care to ensure it is secure & will not come off.
The washer man, July 2010