Before starting to collect function data (A to E), a data collection device (200): communicates with every electronic control device (101 to 107) provided in a system (100) acquires functions (A to E) controlled by the electronic control devices (101 to 107) and creates device-by-device function list information (LD1) which lists the functions by function type and by electronic control device. The data collection device: selects at least one function in order to collect function data communicates, on the basis of the created device-by-device function list information, with the electronic control device(s) corresponding to said at least one function that has been selected and collects function data regarding the function of the selected information.
