A method determines a mobile communications network quality for downloading mobile communications data. Data which quantify the mobile communications network quality in a current location of a respective motor vehicle, is continually acquired using acquisition units provided in the motor vehicle. This data is transferred to a database in which it is stored. A route of a select motor vehicle is determined. A data record quantifying the mobile communications network quality along the route, is retrieved from the database. Mobile communications data is downloaded to a memory of the select motor vehicle taking the data record into consideration. A total data record quantifying the mobile communications network quality is determined at predetermined intervals by a data processing device, taking into consideration the data transferred to the database, and the data record quantifying the mobile communications network for the select motor vehicle is obtained from this total data record.