In a device installed in a vehicle for monitoring a target section in the vehicle, an executing unit executes a specific process for addressing an abnormality in the target section, and an instructing unit instructs the executing unit to execute the specific process when an abnormality occurs in the target section. A determining unit determines when the specific process is required to be checked. A checking unit instructs the executing unit to execute the specific process independently of whether an abnormality occurs in the target section each time it is determined that the specific process is required to be checked, thus checking whether an abnormality occurs in the specific process.