A diagnostic method for analyzing an operation of at least one part of a production line in the tobacco industry through a probe shaped as a smokers' article and including at least one local sensor, a processor, a memory, a data transmission module and an electrical power supply, wherein the production line has a control unit and at least one line sensor, the control unit including a processor, wherein the at least one line sensor is in communication with the control unit and is configured to measure respective machine parameters, representing an operation of at least one element of the line, the method comprising the following steps:
- generating an activation signal;
- transmitting the activation signal to the processor of the probe at a starting instant;
- transmitting the activation signal to the processor of the control unit in synchronous fashion with respect to the step of transmitting the activation signal to the processor of the probe;
- receiving in an electronic database a set of probe data acquired by the probe, in response to the activation signal received, between the starting instant and an end of acquisition instant;
- receiving in an electronic database a set of line data acquired by the control unit, in response to the activation signal received, between the starting instant and the end of acquisition instant;
- temporally correlating the sets of the probe data and of the line data,
- wherein the set of probe data is acquired from the probe, as the probe moves through said at least one part of the production line.