All 2018 FCA (FIAT, CRHSYLER, ALFA ROMEO) vehicles are equipped with SGW Safety Gateway Modules to prevent access to the vehicle from the OBD2 port via a non-original diagnostic scanner. The purpose of this module is to prevent attacks on the vehicle network via the CAN bus.
HOW TO USE FCA 12+8?
Locate and plug the 12 PIN and 18 PIN connectors of the SGW module, then connect the FCA 12+8 directly to the 12 PIN and 8 PIN (two connectors connected to the SGW) connectors on the car. At this point, normal communication with the car can be achieved.