An assembly is described for coupling a towing vehicle to a trailer having a towing vehicle-side coupling unit and a trailer-side coupling unit. A measuring device, which records and analyzes the force acting on the towing vehicle-side coupling unit in at least one direction, is assigned to the towing vehicle-side coupling unit. The measuring device is coupled to a vehicle immobilizer that prevents the towing vehicle from starting and/or being set in motion in response to the force recorded by the measuring device and/or a physical quantity derived therefrom exceeding a predefined threshold value.