Vehicle Operational Definitions
Purpose: To describe the interaction between Reading and Sending messages, High and Low Priorities, Driving Modes, sounds generated, and vehicle state.
Criteria: The following table describes HMI functionality relating priority messages and driving mode when the driver is reading messages.
| READ MESSAGE | Non-Driving Mode | Driving Mode |
| Parking brake set | Parking brake NOT set | |
| Standard Priority | Driver is notified that a new message arrived. Can read messages. | Driver is notified that a new message arrived. Cannot read messages. |
| High Priority |
| SEND MESSAGE | Non-Driving Mode | Driving Mode |
| Parking Brake set | Parking Brake NOT set | |
| Create message | Can create and send messages | Cannot create or send messages |
| Quick Response (discussed in Live meeting held on 1/23/09) | Can "quick" response to incoming messages | Cannot "quick" response to any Incoming message |
| Audible MESSAGE | Non-Driving Mode | Driving Mode |
| Parking Brake set | Parking Brake NOT set | |
| Standard Priority | Driver notified that a new message arrived. Message is spoken. | Driver notified that a new message arrived. Message is spoken. |
| High Priority |
TMC Recommendation: To allow reading and sending messages only if the parking brake is set. Audible messages are spoken.