Hotpoint FDW60 pcb error?

Hi there, my Hotpoint FDW60 dishwasher has a hot water fault - not heating the water during a cycle. It's happened before and needed the pcb repairing which did the trick. I've just fitted a used, working pcb from another dishwasher but I'm now getting a different problem. The programme starts but no water goes into the machine then after around a minute I get a series of four beeps then lights 5&6 (fast and prewash) flash. Indicating a water fault I think. Any suggestions where I'm going wrong please?

Many thanks

JMC69
February 2014