This HiFi adapter converts the factory vehicle wiring into an ISO-compatible interface, allowing for easy installation of an aftermarket radio in Mercedes Vito W447 vehicles from 2014 to 2024. It transmits the signals from the steering wheel remote control and the relevant audio control lines to the new car radio, while preserving the signal paths for the rearview camera and the wiring for the emergency call system. The device is integrated into the original wiring harness and connected directly to the existing harness. This enables a plug-and-play installation without the need to cut the factory connectors. Typical applications include audio upgrades in vehicles where the original steering wheel remote controls, camera function, and compatibility with the emergency call system must be retained for a professional installation or retrofit projects.