A spray system includes nozzles spaced along a distribution line. Each nozzle actuates the position of one or more internal valves based on a spray command received from a system control module. Sensors generate position information regarding the actuation of the valves. The actual valve positions are compared to expected valve positions to determine a deviation between the two. The deviation can be compared to a threshold to determine a status of that nozzle. A normal nozzle status can be generated based on the deviation being less than the threshold. An abnormal nozzle status can be generated based on the deviation being equal to or exceeding the threshold.