Bosch Exxcel Dishwasher?

We have a Bosch Exxcel Dishwasher S9G1B. During any cycle start up, the pump empties any water in the sump area, but then the clean water does not come on. Also when you open the door in cycle, the pump is constantly running until you switch the power off (but water not spraying. During start up after a few seconds a very slight click can be heard (possibly from the main board relay???) - but nothing happens. The water is connected correctly. Oh one other point is if I add about 2-3 litres into the sump then water does spray for just a few seconds until the sump drains it away. Does anyone think it needs a new mother board? Or maybe a new solenoid? Thank you