Audio, Visual & Navigation System (Premium Audio): Overview Nissan Versa II

Component Description

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System Description

Refer to Owner's Manual for navigation and audio system operating instructions.

Audio function and display are built into AV control unit.

This audio system has the following functions.

1. Map data on SD-card
2. Full support for playback of music from iPod® and USB device
3. High resolution color 5 inch display with touch panel function
4. FM/AM twin digital tuner
5. USB mass storage connection
6. Satellite radio
7. Hands-free phone system

iPod® is a trademark of Apple inc., registered in the U.S. and other countries.

Description

1. The navigation system can be operated by control panel of the AV control unit and display (touch panel) of the AV control unit.
2. Guide sound during the operation of the navigation system is output from AV control unit to front speaker.
3. AV control unit calculates the vehicle location based on the signals from GYRO (angle speed sensor), vehicle sensor, and GPS satellite, as well as the map data from map SD-card. The vehicle location is displayed on the AV control unit.

POSITION DETECTION PRINCIPLE

The navigation system periodically calculates the vehicle's current position according to the following three signals

1. Travel distance of the vehicle as determined by the vehicle speed sensor
2. Turning angle of the vehicle as determined by the gyroscope (angular velocity sensor)
3. Direction of vehicle travel as determined by the GPS antenna (GPS information)

The current position of the vehicle is then identified by comparing the calculated vehicle position with map data read from the map SD-card (map-matching), and indicated on the screen as a vehicle mark. More accurate data is judged and used by comparing vehicle position detection results found by the GPS with the result by map-matching.

The current vehicle position will be calculated by detecting the distance the vehicle moved from the previous calculation point and its direction.

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1. Travel distance Travel distance calculations are based on the vehicle speed sensor input signal. Therefore, the calculation may become incorrect as the tires wear down. To prevent this, an automatic distance correction function has been adopted.
2. Travel direction Change in the travel direction of the vehicle is calculated by a gyroscope (angular velocity sensor) and a GPS antenna (GPS information). They have both advantages and disadvantages.

More accurate traveling direction is detected because priorities are set for the signals from these two devices according to the situation.

MAP-MATCHING

Map-matching compares a current location detected by the method in the "Location Detection Principle" with a road map data from map SD-card.

Note. The road map data is based on data stored in the map SD-card.

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The vehicle position may not be corrected under the following circumstances and after driving for a certain time when GPS information is difficult to receive. In this case, the vehicle mark on the display must be corrected manually.

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1. In map-matching, alternative routes to reach the destination will be shown and prioritized, after the road on which the vehicle is currently driven has been judged and the vehicle mark has been repositioned. Alternative routes will be shown in different order of priority, and the incorrect road can be avoided if there is an error in distance and/or direction. Routes are of the same priority if two roads are running in parallel. Therefore, the vehicle mark may appear on either of them alternately, depending on maneuvering of the steering wheel and configuration of the road.
2. Map-matching does not function correctly when a road on which the vehicle is driving is new and not recorded in the map SD-card, or when road pattern stored in the map data and the actual road pattern are different due to repair. The map-matching function may find another road and position the vehicle mark on it when driving on a road not present in the map. Then, the vehicle mark may change to it when the correct road is detected.
3. Effective range for comparing the vehicle position and travel direction calculated by the distance and direction with the road data read from the map SD-card is limited. Therefore, correction by map-matching is not possible when there is an excessive gap between current vehicle position and the position on the map.

Camera Image Operation Principle

1. The AV control unit supplies power to the rear view camera when receiving a reverse signal.
2. The rear view camera transmits camera images to the AV control unit when power is supplied from the AV control unit.
3. The AV control unit combines a warning message and fixed guide lines with an image received from the rear view camera to display a rear view camera image on the screen.

Diagnosis Description

The Bluetooth® control unit has two diagnostic checks. The first diagnostic check is performed automatically every ignition cycle during control unit initialization. The second diagnostic check is performed by the technician using the steering wheel audio control switches prior to trouble diagnosis.

The AV control unit sends sound signals to the front door speakers using the front door speaker circuits.

The AV control unit sends audio signals to the rear door speakers using the rear door speaker circuits.

When one of the steering wheel audio control switches is pushed, the resistance in steering switch circuit changes depending on which button is pushed.

Voice signals are transmitted from the microphone to the Bluetooth® control unit using the microphone signal circuits.

Rear view camera signals are transmitted from the rear view camera to the AV control unit using the camera signal circuits.

Note. For Navigation system operation information, refer to Navigation system Owner's Manual.

BASIC OPERATIONS

Note. Locations stored in the Address Book and other memory functions may be lost if the vehicle's battery is disconnected or becomes discharged. If this occurs, service the vehicle's battery as necessary and re-enter the information in the Address Book.