System Description: Overview: Notes
The navigation system is a highly-sophisticated, hybrid locating system that uses satellites and a map database to show where the vehicle is and to help guide you to a desired destination.
The navigation system receives signals from the global positioning system (GPS), a network of 24 satellites in orbit around the earth. By receiving signals from several of these satellites, the navigation system can determine the latitude, longitude elevation of the vehicle. In addition, signals from the system's yaw rate sensor and the PCM (vehicle speed pulse) enable the system to keep track of the vehicle's direction and speed of travel.
This hybrid system has advantages over a system that is either entirely self-contained or one that relies totally on the GPS. For example, the self-contained portion of the system can keep track of vehicle position even when satellite signals cannot be received. When the navigation system is on, the GPS can keep track of the vehicle position even when the vehicle is transported by ferry.
The navigation system applies all location, direction, and speed information to maps and calculates a route to the destination entered. As you drive to that destination, the system provides both visual and audio guidance.
This navigation system also has voice recognition that allows voice control of most of the navigation functions. The TALK and BACK buttons on the steering wheel activate the voice control. The voice control also allows control of the audio and climate control.
The navigation system provides a trip computer function. The fuel economy display is calculated by data provided by the PCM. The PCM provides fuel use and level data via the F-CAN bus, and a dedicated speed signal.
The illumination signal is used by the navigation unit to automatically switch the display between Night and Day brightness modes when Display is set to Auto. When the instrument panel brightness control is set to full brightness, the navigation system stays in the Day mode, even with the headlights on. Display unit button illumination is supplied through the audio unit.
The GA-Net II bus passes information back and forth between the navigation display, the navigation unit, the climate control unit, and the audio system components. The information passed on this bus are touch button commands, audio muting signal, and audio (radio and XM), when commanded by voice control.
The rear view camera image is shown on the display when in reverse. Camera brightness is adjustable by touching the "Zoom in/Zoom out" button while viewing the camera image.
The clock on the audio unit display is set, and maintained by the navigation unit. The time is automatically adjusted for daylight savings, and time zone changes while driving. The time can be adjusted in the setup menu.
Additional information is available about the navigation components following the System Diagram. A glossary of terms that are used throughout this article follows the detailed information.
The UART serial bus is used to communicate with the climate control unit. Voice commands to adjust climate feature such as, "Climate control full Automatic", are sent over this bus. In return, climate control status (such as the current fan speed) is sent to the navigation unit.