Genuine OEM Volkswagen Diesel Engine Control Unit, part number 04L906056KT. This control unit is responsible for managing the various functions of the diesel engine, including fuel injection, ignition timing, and emissions control. It is typically located in the engine bay. The unit weighs 0.75 kg and has dimensions of 0.19m x 0.18m x 0.04m. Genuine OEM control units are essential for ensuring the correct firmware and sensor calibration, which is critical for reliable engine operation and compliance with emissions standards.