In the last few model years, OEMs started to close diagnostic access with security gateways. FCA/Stellantis did it via SGW, VW Group via SFD / SFD2, and premium brands moved more functions to online sessions. Without the right token or cloud authorization, even a good aftermarket scanner cannot clear DTCs or run bi-directional tests on a 2019+ Jeep or 2024+ VAG platform. :contentReference[oaicite:1]{index=1}
Since ~2017 FCA placed a Secure Gateway (SGW) module between the OBD port and vehicle ECUs. Without authentication, you can only read fault codes — you cannot clear them, run actuator tests or do proxy alignment. Access is normally done through the official AutoAuth service or OEM account. :contentReference[oaicite:5]{index=5}
Important 2025 note: several EU users reported that from 1 Sept 2025 AutoAuth is not fully functional for European IPs; access is limited or requires a different route. Independent workshops must plan alternative authentication (via brand-supported tools or through a proxy service). :contentReference[oaicite:6]{index=6}
Many aftermarket tools (TOPDON, XTOOL, etc.) already integrate SGW unlock inside their cloud — you register the device, log in, and the tool opens SGW for the current VIN. That’s the easiest “legal” path for a small workshop. :contentReference[oaicite:7]{index=7}
VW Group launched SFD around MQB Evo (Golf 8, Octavia IV, Leon IV, A3 8Y) and later expanded to MEB/ID models. SFD blocks adaptation and long coding until your tool gets an online token from VW servers. Each token is VIN-specific and time-limited. :contentReference[oaicite:8]{index=8}
By 2024–2025 VAG pushes SFD2, which is even stricter — you basically need ODIS/GeKo online or a service that emulates a valid VIN/token. There are community solutions, but they are fragile and may break after updates. :contentReference[oaicite:9]{index=9}
New ECUs talk over Ethernet and use DoIP (ISO 13400). Without a DoIP-capable VCI your scanner will simply not see some control units on late BMW, JLR, Mercedes or even VAG EVs. DoIP gives higher bandwidth and fits software-defined vehicles, but it also makes online authorization easier for OEMs. :contentReference[oaicite:10]{index=10}
The market for automotive CAN-FD is growing ~19% CAGR to 2033, i.e. this is the new normal for body, ADAS and EV modules. Your shop’s interface must handle CAN-FD frames or you will miss entire sub-networks in 2025 cars. :contentReference[oaicite:11]{index=11}
Security gateways are not going away — in fact, they will be tighter as more cars become software-defined. Independent workshops that invest in DoIP/CAN-FD hardware and learn to work with SGW/SFD now will keep full diagnostic and coding functionality on 2025+ vehicles, while shops on old scanners will be limited to code reading only. That’s exactly why we publish this deep dive on MHHAuto: to show the practical paths that are still open. :contentReference[oaicite:15]{index=15}