Genuine OEM Volkswagen Control Unit, part number 03L906022JC. This is the main electronic control module for the diesel engine, responsible for managing fuel injection, ignition timing, and other critical engine functions. It is typically located in the engine bay. The unit has dimensions of 0.19m x 0.185m x 0.04m and weighs 1.07 kg. Genuine OEM control units are essential for ensuring the correct firmware and sensor calibration, guaranteeing reliable engine operation and adherence to emissions standards.