A motor vehicle has a first energy store for the operation of multiple vehicle systems and a second energy store which, at least, provides the electrical energy needed to start the motor vehicle, and a control device. A method for testing a first energy store includes connecting the first energy store to a load having a lower impedance than the minimum total impedance of a parallel circuit composed of a fixed selection of the vehicle systems for a fixed time interval by means of the control device, measuring a voltage dropping on the first energy store by means of the voltage measuring device, at least once within the time interval, and outputting a signal by means of the control device if the voltage falls below a predefined limiting value,