Part One
Navigation System Description
Overview
The navigation system is a highly-sophisticated, hybrid locating system that uses satellites and a map database to show you where you are 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, and 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.
The navigation system also uses dynamic route guidance to help avoid traffic delays and incidents. Clients need to subscribe to real-time traffic for this function to work.
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 functions.
The illumination signal (headlights ON) is used by the audio-navigation unit to automatically switch the display between Night and Day brightness modes. When the gauge control module brightness control is set to full brightness, the navigation system stays in the day mode, even with the headlights on.
The GA-Net II communication bus passes information back and forth between the navigation display, the audio-navigation unit, AcuraLink control unit (XM receiver), and the audio system. The information passed on this bus is audio settings directed by the audio-navigation unit.
The Comm. Bus connects the HFL, XM (HIP) (AcuraLink), and audio-navigation units. This bus supports these functions:
- The audio-navigation unit receives traffic, weather, and AcuraLink message information from the AcuraLink control unit (XM receiver).
- If a POI phone number is available, the audio-navigation unit sends the phone number (on the Calculate route to screen) to the HandsFreeLink control unit for dialing.
- If vehicle problems are detected, and the client's cellular contract includes data service (the vehicle must also have an approved blue tooth phone paired and configured correctly), then the AcuraLink control unit (XM receiver) can send vehicle data to the HandsFreeLink control unit for transmitting back to the AcuraLink servers.
- The AcuraLink server can pass additional problem details back through the HandsFreeLink control unit, to the AcuraLink control unit (XM receiver), and finally to the audio-navigation unit for display.
HDD Navigation System
The Acura ZDX uses a HDD (hard disc drive) instead of a navigation DVD. The HDD system improves route calculation and POI searching time, as well as these additional functions:
- Ripping music to the HDD with on-board CDDB (CD database) information provided by Gracenote.
- Clients can save their personal pictures to the HDD and use the images as wallpaper when they are not using the navigation system.
- See the Owner's Manual or Navigation Manual for more information.
There are two software programs that run on the audio-navigation system:
- Navigation system software - This software comes pre-loaded on the HDD and runs the navigation system. It can be updated when a client orders a navigation update disc, or as directed by any official Acura service information like a service bulletin.
- Map software - This is commonly referred to as update navigation DVD that clients can order to update their map info, POI DB, and CDDB information. This also comes pre-loaded on the HDD, but the client can choose to update it yearly.
When you order a reman HDD, the latest navigation system software is loaded on the HDD, along with the latest Map software that the client had installed on their HDD.
If a client wants to order an update, see Ordering an Update Navigation DVD.
The Gracenote CDDB is updated quarterly. Clients can visit www.acura.com and download the latest update.
The HDD shuts down to protect itself from damage, if the audio-navigation unit internal temperature is 183 °F (84 °C) or higher.
Warning of extreme temperatures in the audio-navigation unit is displayed on the navigation screen as an error message.
USB Adapter
The USB module is built into the audio-navigation unit. Clients can load images (which can be used as wallpaper), music, and the CDDB. Not all USB devices and devices functions work with the USB adapter. Please see the Owner's Manual for more information.
Multi-View Rear Camera System
Overview
The multi-view rear camera system is a functionality that provides three different view images of the rearview camera to the navigation display unit, and can be changed by user operation. The guiding lines are different according to the view mode difference. The rearview camera is connected directly to the navigation display instead of the audio-navigation unit to improve the time for the rearview image to appear on the display.
- Normal View Mode
The display shows the basic view.
- Wide View Mode
The display shows wider visibility than the normal view, which helps the driver confirm any objects approaching from right and left.
- Top Down View Mode
The display shows the view from the top angle of the vehicle, which helps the driver confirm the distance from any object behind.
When the vehicle is in R position, the rearview camera image automatically appears on the navigation display. You can change the display while the vehicle is in R position by pressing the interface dial.
ENTER:
The rearview camera image changes between the wide view, the normal view, and the top down view in this order.
CANCEL button:
Pressing and holding the CANCEL button for three seconds turns the guide lines on and off.
INTERFACE DIAL:
You can change the rearview camera image brightness by rotating the interface dial. The brightness adjustment is not affected by the screen brightness adjustment in Setup.
Basic Control
When the navigation display detects the BACK UP LIGHT signal (when the vehicle is in R position) for at least 0.5 seconds, the navigation display turns on the rearview camera. The navigation display delays for the 0.5 seconds to prevent changing the screen image too frequently because of incorrect shift lever selection.
Changing Camera Views
1. When the rearview camera image is displayed, pressing the interface dial in (ENTER) sends a signal from the audio-navigation unit, to the navigation display unit using the GA-Net BUS to change the camera angle view.
1. The navigation display unit recognizes the signal, and sends a signal to the rearview camera using the CAMERA BIT0 and CAMERA BIT1 signal lines to change the rearview camera view.
2. The rearview camera takes the digital video using the input signal, then sends the rearview image to the navigation display unit using the NTSC lines. The rearview image appears on the navigation display unit.
View Mode Memorization
Any time the audio-navigation unit loses power (battery disconnected, navigation unit disconnected, etc.) the rearview camera defaults to the normal angle view. The rearview camera will also default to this angle if you had the top down angle selected when you turned the ignition switch to LOCK (0) or pressed the engine start/stop button to select the OFF mode. If you change the rearview camera to the wide angle view, the camera will remember this view when you turn the ignition switch to ON (II) or press the engine start/stop button to select the ON mode.
System Diagram
USA Models
Canada Models
Navigation Function
The navigation system is composed of the audio-navigation unit, the PCM (vehicle speed pulse), the AcuraLink control unit (XM receiver) (traffic and weather information), the HandsFreeLink control unit (to send a POI phone number or place a call), the GPS antenna, the microphone, the voice control switch, the navigation display unit, interface dial, rearview camera, and the audio-navigation and HVAC switch panel.
Function Diagram
GA-Net Bus Configuration
The GA-Net bus passes audio, navigation, and HFL commands throughout the audio, navigation, and HFL components. These commands include navigation audio/XM selections by voice, and XM station and music title names. Because the entire bus is interconnected between components, an open or short in the GA-Net bus harness may cause any or all of these functions to become inoperative.
Vehicle Speed Pulse
The vehicle speed pulse is sent by the PCM. The PCM receives a signal from the output shaft (countershaft) speed sensor, then processes the signal and transmits it to the speedometer and other systems.
Yaw Rate Sensor
The yaw rate sensor (located in the audio-navigation unit) detects the direction change (angular speed) of the vehicle. The sensor is an oscillation gyro built into the audio-navigation unit.
Sensor Element Structure
The sensor element is shaped like a tuning fork, and it consists of the piezoelectric parts, the metal block, and the support pin. There are four piezoelectric parts: one to drive the oscillators, one to monitor and maintain the oscillation at a regular frequency, and two to detect angular velocity. The two oscillators, which have a 90-degree twist in the center, are connected at the bottom by the metal block and supported by the support pin. A detection piezoelectric part is attached to the top of each oscillator. The driving piezoelectric part is attached to the bottom of one oscillator, and the monitoring piezoelectric part is attached to the bottom of the other oscillator.
Oscillation Gyro Principles
The piezoelectric parts have electric/mechanical transfer characteristics. They bend vertically when voltage is applied to both sides of the parts, and voltage is generated between both sides of the piezoelectric parts when they are bent by an external force. The oscillation gyro functions by utilizing this characteristic of the piezoelectric parts and Coriolis force. (Coriolis force deflects moving objects as a result of the earth's rotation.) In the oscillation gyro, this force moves the sensor element when angular velocity is applied.
Operation
- The driving piezoelectric part oscillates the oscillator by repeatedly bending and returning when an AC voltage of 6 kHz is applied to the part. The monitoring-side oscillator resonates because it is connected to the driving-side oscillator by the metal block.
- The monitoring piezoelectric part bends in proportion to the oscillation and outputs voltage (the monitor signal). The navigation unit control circuit controls the drive signal to stabilize the monitor signal.
- When the vehicle is stopped, the detecting piezoelectric parts oscillate right and left with the oscillators, but no signal is output because the parts are not bent (no angular force).
- When the vehicle turns to the right, the sensor element moves in a circular motion with the right oscillator bending forward and the left oscillator bending rearward. The amount of forward/rearward bend varies according to the angular velocity of the vehicle.
1. The detecting piezoelectric parts output voltage (the yaw rate signal) according to the amount of bend. The amount of vehicle direction change is determined by measuring this voltage.
Global Positioning System (GPS)
The global positioning system (GPS) enables the navigation system to determine the current position of the vehicle by using the signals transmitted from the satellites in orbit around the earth. The satellites transmit the satellite identification signal, orbit information, transmission time signal, and other information. When the GPS receiver receives a signal from four or more satellites simultaneously, it calculates the current position of the vehicle based on the distance to each satellite and the satellite's position in its respective orbit.
Position Detection Image with GPS Satellite
