Motor vehicle dashboard indicators with an intelligent computer network interface

An indicator unit is provided to display information to occupants in a motor vehicle. The indicator unit is adapted for connection to a communication network and intercepts messages that carry data between other vehicle equipment. A control circuit is programmed to identify the existing network messages that carry the data needed for the information display. The control circuit operates a display device in response to received data. Because the indicator eavesdrops on the network and intercepts existing data messages, other equipment in the motor vehicle do not have to be programmed to communicate specifically with the indicator. This facilitates adding specific indicators to a particular truck.