Genuine OEM Volkswagen Control Unit, part number 03C906021S350. This control unit is essential for managing the complex operations of a petrol engine, including fuel injection, ignition timing, and emissions control. It is typically located in the engine bay. The '350' suffix denotes a specific variant of this control unit. Genuine OEM parts are critical for control units as they guarantee the correct firmware, calibration, and sensor interface, ensuring reliable and efficient engine operation.