Diplomat Integrated D/washer?

Hi, no water is coming through the arms during a wash - the machine seems to be working well ie: steaming and water sounds being made but for some reason the arms are not going around and no water is coming out from them. Water is filling up at the bottom of the machine but it is also draining out at the end of cycle too. My husband has taken all the parts apart but cannot see any blockages etc. The nozzles on the arms arent blocked either. No error message is coming up and none of the lights are flashing either like other posts I have read. Any help appreciated. Thanks