A compressed air supply system for a utility vehicle includes an air dryer unit provided with a filter unit, an electrically controllable valve unit and a pneumatically controllable discharge valve unit, a compressor with a coupling, which supplies compressed air to the air dryer unit via a delivery pipe, a multi-circuit safety valve unit which removes the compressed air from the air dryer unit, and an electrically controllable compressor coupling switch valve unit. An electronic control unit controls or regulates the functions of the air dryer unit and the compressor coupling switch valve unit.