The disclosure presents a geared motor unit including a housing having an electric motor formed of a coiled stator assembly and of a magnetized rotor, the housing further including a printed circuit board for connecting and controlling the motor, a movement-reducing gear train, a sensor magnet and a magnetosensitive probe. The gear train includes a toothed movement output gear, the sensor magnet being ring-shaped and being rigidly connected to the output gear. An output gear is extended on either side of the sensor magnet by two guides cooperating with the two opposite walls of the housing; a ring-shaped magnet surrounds the axis of rotation of the output gear; a printed circuit board includes a controller controlling the motor and extends up to the vicinity of the output gear. The printed circuit board includes, in the area located in the vicinity of the output gear, the magnetosensitive probe which is connected directly, electrically and mechanically, to the area and is located axially or radially facing a ring-shaped magnet.