In one aspect, a method is carried out in a system including diagnosis plug-in device, a host server, diagnostics database suppliers, and on-board ECUs, with the method including coupling the diagnosis plug-in device to the diagnosis port of a vehicle of interest having a certain vehicle type defined at least by the Make/Model/Year/Powertrain of the vehicle of interest; causing the diagnosis plug-in device to listen on a diagnosis and receiving frames broadcasted by onboard ECUs; after said Bus Active condition is detected, determining a frame profile according to characteristics of the received frame-IDs; determining vehicle type from the frame profile, with the help of a frame profile lookup table; and providing a diagnosis stacks dataset database at the diagnosis plug-in device or at the host server, said diagnosis stacks dataset comprising at least available request/answer services for the vehicle type of interest.