The solenoid performs a critical function in your dishwasher cleaning process and is responsible for opening the drain valve. The trigger for the solenoid to open the drain valve is the timer control.
If the valve does not open, it could be due to a faulty solenoid or timer control. To determine which component is defective is best done by a skilled technician. If the technician determines that both the solenoid and the timer control are working correctly, this could indicate that your dishwashers inlet valve is clogged.