Abstract: Methods for testing a control unit of a vehicle. The control unit obtains calculated surrounding-area data of a simulated surround sensor, and obtains calculated motion data of a simulated vehicle. The calculated motion data are transmitted to the control unit via a simulated vehicle data bus. Using a sensor testing unit, the calculated surrounding-area data are transmitted to the control unit via a sensor-data transmission circuit different from the vehicle data bus. To execute a simulated acquisition of surrounding-area data, using the control unit, a command for executing a measurement is transmitted to the sensor testing unit, data for identifying the position of the simulated surround sensor is transmitted to the computer device, positions of points of reflection by simulated objects in the surrounding area of the vehicle are calculated and transmitted to the sensor testing unit, and calculated surrounding-area data are determined and transmitted to the control unit.