A control device for a restraining system in a motor vehicle is proposed, a safety switch, which also includes a watchdog, performing the function of a safety switch in the control device. The safety switch monitors sensor signals which are transmitted to the processor of the control device for plausibility and triggers appropriate restraining systems via a time unit for a predefined time period only when the safety switch itself detects a trigger event. On the basis of supplementary data from the sensor signals, the safety switch infers how the sensor signals are to be processed. The safety switch is designed such that it triggers the restraining systems correspondingly assigned to the sensors. When the control device is switched on, the processor performs a test of the safety switch by generating a test signal using the sensors.