Systems and methods are directed to monitoring the status of a vehicle controller or other autonomy system during operation of an autonomous vehicle. In one example, a system includes one or more processors; and memory storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations. The operations include obtaining a message from a vehicle controller. The operations further include, based at least partly on the message, determining whether a failure mode exists. The operations further include providing, in response to determining the failure mode exists, one or more commands to implement a safety measure response for the autonomous vehicle.