The circulation pump is your dishwasher's motor. It sucks up the water that has entered the tub in order to send it to the spray arms. The water goes through several filters and returns to the pump for a new cycle.
Have you noticed the motor is heating up or is making strange noises? In either of these cases, it probably means your motor is defective.
Have you noticed that your washing up isn't being done properly? Perhaps there is a leak from the circulation pump.
If you want to replace your dishwasher's circulation pump, order it from our site! We offer various models that will fit your machine.