A control device for regulating a volume flow of a fluid in a drive train of a motor vehicle includes a torque monitoring unit, set up to determine, on the basis of a characteristic diagram of the pump which describes a functional dependency of the torque to be applied by the drive motor on the rotational speed of the drive motor for a predetermined fluid state of the fluid, a current torque deviation occurring between the current torque and the torque given by the characteristic diagram for the current rotational speed, and a correction unit, set up to correct a power setting signal for the drive motor in accordance with the current torque deviation and to provide a corrected power setting signal, and a power regulation unit, set up to generate a second power setting signal for actuating the drive motor on the basis of the corrected power setting signal.