Its possible the drain pump is blocked. If you find the end of the flexy waste pipe which comes out the back of the machine and blow down it it should blow the blockage back into the machine, failing this there maybe something lodged in the propellor which needs removing. if this doesn't work it is probably the waste pump motor itself which has failed. you can buy the part from www.commercialdishwashersuk.co.uk or www.easicook.co.uk
Jeremy Staniforth, July 2007