From around the beginning of 2018, more and more FCA models are equipped with a Security GateWay (called SGW) for the EOBD diagnostic system. SGW stands for Security GateWay. Popularly called a Firewall, intended to keep intruders outside. As a result, only officially certified diagnostic equipment is admitted to the internal communication network (CAN network). A car is diagnosed via the CAN network. But also servicing, error messages are removed by the CAN network and factory updates can be performed.
With the SGW bridge this firewall can be bypassed. This is not just a set of interconnections but a small electronic circuit, so it can be interchanged with the original SGW without issues.
Note: to make the SGW bridge invisible for official diagnostics, a software adjustment (proxi alignment) to the body computer is needed.