Unlocking system for a trailer coupling of a motor vehicle

The device has a locking bolt (7) located into a ball bar bearing head that is connected to a push rod. An actuator device is arranged between the push rod and a drive unit. The drive unit forms an electric motor unit. A single-arm control lever (14) forms the actuating device. The control lever is directly attached to the push rod of the locking bolt and operatively connected with the electric motor unit. A facing end of the push rod is interpositioned with a connecting device (16) that is connected with the push rod. The connecting device is formed by a retainer fork.