The invention relates to methods and devices for actuating a parking brake in a gearbox which is actuated in an automated manner, whereby gear changes are carried out by means of at least one electrically driven actuator, gear positions can be selected by means of a selector device, and the parking brake can be activated by means of the selector device when the vehicle is stationary or moving slowly. The invention also relates to a vehicle provided with an additional gearbox. The ignition key can only be removed, according to the inventive methods and devices, when the gearbox is in the P state and the additional gearbox is not in the N state. The invention further relates to a method and device, whereby the additional gearbox can only be shifted in the N state when the gearbox is not in the P state. Disclosed are also methods and a device for carrying out the same, by which means automated manual gearboxes, especially parallel gearboxes, are controlled in such a way that the vehicle can be safely parked and can set off in a reliable and comfortable manner.