Abstract: A monitoring and control system for a fluid container filler line having an empty container in-feed conveyor (11), a multivalve fill station (14), a multihead scanner station (17), a discharge conveyor (20) and a fill height detector (25), the system comprising a sensing module (22) having a first sensor (44) to indicate the first of a sequence of numbered valves with means to reset a valve counter, a second sensor (45) to count each valve of the sequence and controller means (50) responsive to said sensors to spacially track each container (12) through the system and to identify the particular fill valve for each particular container. A detector (54) is responsive to the controller and signals from the height detector to detect an improperly filled faulty container and identify the particular number valve which did the faulty filling.