The invention relates to a method for operating at least one ultrasonic sensor (4, 6) of a driver assistance system (2) in a motor vehicle (1), wherein an output sound signal (SA) of the ultrasonic sensor (4, 6) is modulated in accordance with a type of modulation and by means of this modulation, a specific codeword is impressed on the output sound signal (SA). For at least two mutually different functionalities (8 to 12) of the driver assistance system (2), different types of modulation are in each case used for the modulation of the output sound signal (SA) and/or in each case different lengths of the codeword.