Abstract: An integrated message system for a vehicle provides an extendable, prioritized message scheme. Using this scheme, the message system acts as a centralized message provider for variety of alerts and operating data originating throughout the vehicle. The message system defines a hierarchy of message levels, each having a unique output protocol. The protocol defines attributes associated with messages at a particular level such as textual or graphical message, an auditory alert, as well as the scheme for playing these messages and alerts. The system integrates a variety of subsystems that conventionally have separate driver interfaces such as a collision warning system and an adaptive cruise control system.

Abstract: A ventilation display system determines when a ventilation system has remained in recirculation mode for a predefined time, and in response generates a stale air alert message inside the cab of a truck. The system can generate messages alerting the driver that the HVAC system has switched into recirculation mode, and alerting the driver that the recirculation mode has remained active for the predefined time. When equipped with a CO.sub.2 sensor, the system can generate air quality messages based on either the status of the recirculation mode or the level of CO.sub.2 in the cab of the truck or both.

Abstract: An improved fuel economy device computes a filtered rate of change of instantaneous fuel economy or a filtered instantaneous fuel economy and repetitively updates a graphical display depicting the current fuel economy. The fuel economy can be displayed as a percentage of a target fuel economy, programmed by the driver or other operator of the vehicle.