An interface module in a vehicle that provides for the vehicle a connection to a communication network, for example the Internet, and executes the function of a watchdog for the components in the vehicle connected to it. For this purpose, a processor of the interface module performs a function test of the connected components at specified time intervals and sends a function signal as a function of this function test. If at least one component is not functioning properly, the processor restarts the component concerned. This is achieved for example by switching a circuit breaker.