Genuine OEM Volkswagen Control Unit For Diesel Engine, part number 03L997557P. This electronic control unit is responsible for managing the complex operations of the diesel engine. It is typically mounted in the engine bay or under the dashboard. Key specifications include a weight of 0.419 kg and dimensions of 0.18m x 0.2m x 0.04m. Genuine OEM control units are essential for maintaining the precise calibration and firmware required for optimal engine performance and emissions control.