Genuine OEM Volkswagen Control Unit for Diesel Engine, part number 04L906026ST. This electronic control module is responsible for managing various engine functions, including fuel injection and ignition timing. It is typically located within the engine bay. The unit has dimensions of 0.206m x 0.185m x 0.04m and weighs 0.967kg. Genuine OEM parts are critical for control units as they ensure correct firmware, sensor calibration, and signal characteristics for reliable engine operation.