The navigation system consists of a navigation module, compass, antenna, CD auto changer and special audio control unit. The navigation system provides the driver with direction information to a pre-programmed destination.
The system uses Global Positioning System (GPS) satellites to track the location of the vehicle against a digital map, in the form of a CD that is inserted into the navigation module. Direction information is provided to the driver in the form of a visual instruction, on the radio LCD display and a verbal instruction over the audio speakers.
Destination information is input by the driver using buttons on the vehicle audio control unit that access a menu procedure.
Antenna
The antenna is used to gather location information from the GPS satellites. In order to obtain the most accurate location data at least four satellites are required to be visible to the system.
The information gathered is passed to the navigation module, where it is used as comparative data against the digital map. The signal is accurate to 100 metres.
Compass
CAUTION:The navigation compass is a sensitive instrument, care in handling must be maintained at all times.
The compass operates by sensing very small changes in the earths magnetic fields as the vehicle moves or changes direction. This information is passed to the navigation module where it is used to determine that the vehicle direction and changes in direction are consistent with the programmed route.
Navigation Module
The navigation module has three main functions. To monitor, maintain and manage the inputs from the antenna, compass and ABS module. To act as the system interface with the driver display and input (audio control unit). It also acts as storage and access to the information required by the system, the digital map, voice information and operating data. To provide the test, calibration and fault diagnosis procedures. The module is able to check and identify any faults in the system and display these as a specific fault code to aid repair and maintenance.
CD Autochanger
The CD autochanger acts as the communication link between the navigation module and the audio control unit. No other navigation system function is performed by this equipment.
The radio operation is completely standard when navigation is not selected. When navigation is selected the audio control unit acts as the driver interface, having extra functionality that allows the driver to input his required destination, via a menu and provides direction information both visually and audibly. For a detailed description and operation, For additional information, refer to Section 415-01 Audio Unit.
When a navigation system is fitted the ABS module provides information to the navigation system to allow the system to determine distance covered. The input is generated from the ABS wheel sensors on the non-driven wheels of the vehicle. The signals being processed by the ABS module and passed to the navigation module in the format of a pulsed input. For a detailed description and operation, For additional information, refer to Section 206-09A Anti-Lock Control / 206-09B Anti-Lock Control - Traction Control.
