Navigation System Description

Overview

The navigation system is a highly sophisticated, hybrid locating system.

The navigation unit uses global positioning system (GPS) satellite signals, internal yaw and vehicle speed inputs, and a map database to show you where you are and to help guide you to a desired destination.

The navigation unit's GPS receiver receives signals from the 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.

Signals from the system's yaw rate sensor (inside the navigation unit) detects turns, and the ECM vehicle speed pulse (VSP) and reverse signal enable the system to keep track of the vehicle's speed and direction of travel. The advantage of this hybrid system is that the system can track your position if either the GPS signal or the vehicle speed signal is missing. For instance, when in a tunnel (no GPS), the speed signal is used to update your position on the map. Alternately, while the vehicle is being transported on a ferry, GPS signals can show the vehicle position on the map as it crosses the water.

The navigation system uses the location, direction, and speed information to display the appropriate map and calculate a route to the destination entered. As you drive to a destination, the system provides both visual and audio guidance. Audio guidance is sent to the audio unit, and an RGB graphics color signal is sent to the navigation display.

This navigation system also has voice recognition that allows voice control of most of the navigation, and audio, and climate control functions. The voice control switches (TALK and BACK buttons on the steering wheel) activate the voice control system. The microphone on the ceiling receives your voice commands. For more information on this feature, consult the navigation owner's guide.

The illumination signal is used by the navigation unit to automatically switch the display mode between the ‘‘Night'' and ‘‘Day'' display modes. When the headlights are on, the dash brightness control setting ‘‘full brightness'' overrides the ‘‘Night'' display mode, and allows a daytime navigation display with the lights on.

When the navigation system is giving voice guidance commands, all of the speakers are muted. When the voice control system is being used (TALK button pressed), all of the speakers are muted.

The internal GA-Net II bus passes information back and forth between the navigation display, the navigation unit, and the audio system components. The information passed on this bus are select screen commands, audio muting signal, audio (radio), and any open in these bus line can affect the navigation system or other audio accessory operation.

The clock on the audio-HVAC subdisplay unit 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 setup.

Additional information is available about the navigation components following the System Diagram. A glossary of terms that are used throughout this section follows the detailed information.

The Navigation Users Guide in the glove box covers all of the system functions and settings. Use this as a resource when evaluating a customer concern.

System Diagram

Navigation Function

The navigation system is composed of the navigation unit, the ECM (vehicle speed signal), the GPS antenna, microphone, voice control switch, audio unit, climate control unit, navigation display and the interface dial.
These units communicate with each other on the GA-Net bus.

Function Diagram

Vehicle Speed Pulse

The vehicle speed pulse is sent by the ECM. The ECM receives a signal from the countershaft speed sensor, then it processes the signal and transmits it to the speedometer and other systems.

GA-Net Bus Configuration

The GA-Net bus passes audio and navigation commands throughout the navigation and audio components.
These commands include navigation selected screen and hard button signals, audio selections by voice, music, and title names. Because the entire bus is ‘‘daisy chained'' between components (see diagram below), any open or short in the GA-Net bus harness will cause any or all of these functions to become inoperative. The addition of any factory audio accessory must maintain the continuity of the GA-Net bus by installing the ‘‘Y'' cable included with the accessory kit.

Yaw Rate Sensor

The yaw rate sensor (located in the navigation unit) detects the direction change (angular speed) of the vehicle. The sensor is an oscillation gyro built into the 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 piezoelectoric 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

1.	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.

2.	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.

3.	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).

4.	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.

5.	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 three or more satellites simultaneously, it calculates the current position of the vehicle based on the distance to each satellite and the satellite's positions in its respective orbit.

Position detection Image with GPS satellite

Precision of GPS

The precision of the GPS varies according to the number of satellites from which signals are received and the view of the sky. The precision is indicated by the color and shape of the GPS icon shown on the display.

GPS ICON	NUMBER OF SATELLITES	CONDITION	DESCRIPTION
No GPS icon shown	2 or less	Impossible to detect vehicle position	GPS function is normal. The satellite signals received by the GPS are too few to detect the vehicle position.
Square GPS icon shown with white ‘‘GPS''	3	Vehicle position detectable in 2 dimensions	The longitude and latitude of the vehicle position can be detected. (Less precise than detection in three dimensions)
Cube GPS icon shown with green ‘‘GPS''	4 or more	Vehicle position detectable in 3 dimensions	The longitude, latitude and the altitude of the vehicle position can be detected. (More precise than detection in two dimensions)

GPS Antenna

The GPS antenna amplifies and transmits the signals received from the satellites to the GPS receiver.

GPS Receiver

The GPS receiver is built into the navigation unit. It calculates the vehicle position by receiving the signal from the GPS antenna. The vehicle position and signal reception condition is transmitted from the GPS receiver to the navigation control unit to adjust vehicle position.

Navigation Unit

The navigation unit calculates the vehicle position and guides you to the destination. The unit performs map matching correction, GPS correction, and distance tuning. It also controls the menu functions and the DVD-ROM drive, and interprets voice commands. With control of all these items, the navigation unit makes the navigation picture signal, then it transmits the signal to the navigation display and audio driving instructions to the audio unit.

Calculation of Vehicle Position

The navigation unit calculates the vehicle position (the driving direction and the current position) by receiving the directional change signals from the yaw rate sensor and the travel distance signals from the ECM vehicle speed pulse (VSP) signal.

Map Matching Tuning

The map matching tuning is accomplished by indicating the vehicle position on the roads on the map. The map data transmitted from the DVD-ROM is checked against the vehicle position data, and the vehicle position is indicated on the nearest road. Map matching tuning does not occur when the vehicle travels on a road not shown on the map, or when the vehicle position is far away from a road on the map.

GPS Tuning

The GPS tuning is accomplished by indicating the vehicle position as the GPS's vehicle position. The navigation unit compares its calculated vehicle position data with the GPS vehicle position data. If there is large difference between the two, the indicated vehicle position is adjusted to the GPS vehicle position.

Distance Tuning

The distance tuning reduces the difference between the travel distance signal from the VSP and the distance data on the map. The navigation unit compares its calculated vehicle position data with the GPS vehicle position data. The navigation unit then decreases the tuning value when the vehicle position is always ahead of the GPS vehicle position, and it increases the tuning value when the vehicle position is always behind the GPS vehicle position.

Route Guidance

The navigation unit can calculate different routes to a selected destination. You have five options:

Fast Route - Calculate a faster route.
Easy Route - Calculate a route that minimizes the number of turns needed and uses wide roads as much as possible.
Minimize Motorway - Calculate a route that avoids motorway travel. If that is not possible, keep the amount of freeway travel to a minimum.
Mimimize Toll Roads - Calculate a route that avoids, or minimizes travel on toll roads.
Short Route - Calculate a shorter route.

Audio Guidance

The navigation unit transmits audio driving instructions before entering an intersection or passing a junction.
The audio instructions come through the audio unit to the front speakers.

NOTE: The front speakers are muted whenever the navigation system is giving guidance commands, and all of the speakers are muted when the voice control system is being used.

DVD-ROM

The map data (including all scale rates) is stored in the DVD-ROM. The map data includes:

Road distances, road widths, speed limits, traffic regulations, passing time at junction, distances to junctions, and the driving instructions for audio guidance.
Latitude and longitude GPS.

Muting Signal Logic

The audio muting logic is orchestrated by the audio unit. The audio unit determines what audio source has prority to use the speakers.

The priority of the audio sources is as follows:

HFT has the highest priority, followed by navigaton, and finally the radio/CD player. The priority is passed by HFT to the audio unit by dedicated mute wires. The navigation mute signal is passed to the audio unit on the GA-net bus.

The navigation unit temporarily disables the voice control buttons, but allows guidance to be heard. In addition, the audio unit suppresses the output from the radio, disc player, or other audio accessories.

When the navigation system sends out a voice route guidance command, the audio front center speaker is muted, and the navigation voice is heard in the front speakers.

When the navigation voice control system is in use, all of the speakers are muted, and the navigation voice prompts are heard in the front speakers.

Audio Unit

The audio unit receives the audio driving instructions from the navigation unit, and transmits the instructions through the front speakers even when the audio system is in use.

Navigation Display

The navigation display uses liquid crystal display (LCD). The LCD is a 7-inch-diagonal, thin film transistor (TFT), stripe type with 336,960 picture elements, The color film and fluorescent light are laid out on the back of the liquid crystal film.

Microphone

The microphone (on the ceiling, near the front map light) receives voice commands and transmits them to the navigation unit or Hands Free Telephone unit for interpretation.

Talk Button

Activates the voice control system in the navigation unit to accept voice commands.

Back Button

Returns the display to the previous screen (similar function as the CANCEL button).

Glossary

The following is a glossary of terms pertaining to the Voice Recognition Navigation System.

Item	Definition
Breadcrumbs	Off road tracking dots that can be followed on the map to retrace your route back to a mapped (digitized) road. This function can be turned on/off in Setup screen 1.
CPU	Central Processing Unit. The main device within the navigation unit that coordinates the rest of the electronic functions.
Database	This consists of the Map data, and the POI (Points Of Interest) data stored on the DVD.
Dead Reckoning	The use of the speed signal, and yaw rate sensor to position the vehicle on the map even when the GPS signal is obscured by tall buildings, or while driving in a tunnel.
Digitized Road	A road that appears on the navigation screen. The road name will appear at the bottom of the navigation screen. If the user drives ‘‘off road'', the navigation system will display ‘‘Not on a digitized road''. The ‘‘breadcrumbs'' will appear after driving for 804,5 m.
Disclaimer Screen	Screen containing cautionary information. It is meant to be read carefully and acknowledged by the customer when using the navigation system.
DVD or DVD-ROM	Digital Versatile Disk. The navigation program and database resides on this disk. See the Navigation Owner's Manual for information on how to order a replacement or update DVD.
ECM	Engine Control Module. Typically referred to as the ECM.
FAQ	Frequently Asked Question. See the Navigation Owner's Manual for a list of the customer FAQs, and troubleshooting information.
GA-Net bus	Units communication line.
GPS	Global Positioning System. A network of 24 satellites in orbit around the earth. The navigation system can simultaneously receive signals from up to 12 satellites to accurately position the vehicle on the map.
H/U	Head Unit.
Initialization	This refers to the period needed to re-acquire the GPS satellite orbital information whenever the navigation system power has been disconnected. This can take from 10 to 45 minutes.
LCD	Liquid Crystal Display (the navigation screen)
Map Matching	The received GPS information allows the navigation system to position the vehicle on the map. Map matching has occurred if the map screen is displaying the current street name in the bottom-shaded area.
Mic	Abbreviation for the microphone used for receiving voice commands. It is located near the map light in the ceiling.
MW	Maneuver Window. While on-route to a destination, this window displays information about the next maneuver.
Navi	Abbreviation for the Navigation System
Off Route	This occurs when the user leaves mapped roads. Off road tracking dots (‘‘breadcrumbs'') are displayed if the option is enabled in Setup. The user can use them to return to a mapped road. The bottom of the navigation screen will say ‘‘Not on a digitized road''. Breadcrumbs will appear after driving for 804.5 m.

Item	Definition
Outlying Areas	These are rural areas that typically have only their main roads mapped. All other roads are shown in light brown for reference only, since they have not been verified.
POI	Point Of Interest. These are the businesses, schools etc. found under the ‘‘places'' option on the main menu.
Polygon	Colored areas on the map screen denoting parks, schools etc. See the Navigation Owner's Manual ‘‘Traveling to Your Destination'' for a list of the assigned colors.
QWERTY	Keyboard layout resembling the typewriter keys. The keyboard layout can be changed to an alphabetical layout in the Setup mode.
SCS connector	The 2-pin connector used to put the navigation system into the diagnostic mode.
Tuning	A continual update of internal navigation system scaling factors. See the individual sensor tuning discussions under either ‘‘System Description'', or ‘‘System Diagnosis Mode'' in this manual.
Unverified Streets	These streets have not been verified for turn restrictions, one-way, etc. They are shown in light brown on the map. You can enter address destinations in these areas, but depending on your ‘‘Unverified Routing'' choice in setup, voice guidance may end at the last verified street closest to your destination.
Verified Streets	These streets consist of the detailed metropolitan coverage areas, and all other inter-town connection roads. These roads are shown in black on the map.
VP	Vehicle Position. When in map mode, this circular icon shows the vehicle position on the map. Touch this icon to show the latitude, longitude, and elevation of your current position.
VR	Voice Recognition. This allows voice control of many of the navigation functions. The hardware consists of the microphone, steering wheel (Talk/Back) buttons, and the front speakers. See the overview for more information.
VSP	Vehicle Speed Pulse. This pulse signal coming from the ECM is used to update the Vehicle position on the map. These pulses do not indicate direction (forward or backward). When in reverse, the navigation receives a signal from the MICU and directs the VP to move backwards on the map.
VSS	Vehicle Speed Sensor. The counter shaft speed sensor reads the output shaft speed at the transmission and provides a speed pulse to the ECM. The ECM sends this pulse to the navigation system.
Yaw Sensor	This device is located in the navigation system control unit and senses the side-to-side twisting force generated when the vehicle turns. See a detailed description of how this sensor works in this manual.

Navigation Unit Inputs and Outputs for Connector A (20P)

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
1	WHT	R SIG (Red signal)	Red color signal	0-1 V AC	If open: Red color missing (see ‘‘RGB Color'' diagnostic). If short to ground: Red color missing (see ‘‘RGB Color'' diagnostic).
2	RED	G SIG (Green signal)	Green color signal	0-1 V AC	If open: Green color missing (see ‘‘RGB Color'' diagnostic). If short to ground: Green color missing (see ‘‘RGB Color'' diagnostic).
3	GRY	SIG SHIELD GND (Shield signal)	Shield for terminal No. 1, 2, 11, 12, 13	0 V	If open: No change to display. If short to ground: No change to display.
4	ORN	SI (A/C Signal input)	A/C input signal	0-battery voltage pulses	If open: Voice control does not work. If short to ground: Voice control does not work.
5	GRY	ILL (+) (Illumination positive)	Parking light on signal from dash and console lights, under-hood ‘‘Relay fuse box''	Lights on=battery voltage, Lights off=0 V	If open: When brightness=‘‘Auto'', night mode for the display is inoperative when lights on. If short to ground: Blows fuse No. 14 (7.5 A) in under-dash fuse/relay box.
9	GRY	ECU BUS (GA-NET) SHIELD GND (Shield display bus)	Shield for display bus terminal No. 10, 20	0 V	If open: No change to display. If short to ground: No change to display.
10	GRN	ECU BUS (+) (GA-NET) (Display bus positive)	Data bus (+) GA-Net	0-5 V pulses average 2.5 V depends on bus traffic	If open: Navigation buttons and touch screen do not work. If short to ground: Navigation buttons do not work.

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
11	YEL	B SIG (Blue signal)	Blue color signal	0-1 V AC	If open: Blue color missing (see ‘‘RGB Color'' diagnostic). If short to ground: Blue color missing (see ‘‘RGB Color'' diagnostic).
12	BLK	C SIG (Composite signal)	Composite video (vertical/horizontal) Synchronizing signal	0.3 V AC	If open: Picture rolls horizontally, colors still visible. If short to ground: Picture rolls horizontally, colors still visible.
13	GRN	GND SIG (Ground signal)	Ground for color signal	0 V	If open: No change to display. If short to ground: No change to display.
14	PUR	SO (A/C Signal output)	A/C output signal	0-battery voltage pulses	If open: A/C voice control does not work. If short to ground: A/C voice control does not work.
15	BRN	CLK (A/C Clock signal)	Time set sync signal	0-battery voltage pulses	If open: A/C voice control does not work. If short to ground: A/C voice control does not work.
17	WHT	JOG (Jog)	Interface dial operation signal	0-5 V palses	If open: You cannot operate navigation system If short to ground: You cannot operate navigation system
19	BLK	JOG SHIELD (Shield jog)	Shield for interface dial signal	———	———
20	RED	ECU BUS (-) (GA-NET) (Display bus negative)	Data bus (-) GA-Net	0-5 V pulses nominally 2.5 V	If open: Navigation buttons and touch screen do not work. If short to ground: Navigation hard and touch buttons work OK.

Navigation Unit Inputs and Outputs for Connector B (14P)

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
4	RED	RG R (+) (Route guidance voice right positive)	Right audio signal of voice guidance, and Voice Recognition (VR) prompts	Audio signal 0,004-0.04 V	If open: If voice activated, radio speakers buzz; if voice of, no effect. If short to ground: If voice activated, radio speakers buzz; if voice off, no effect.
5	WHT	RG L (+) (Route guidance voice left positive)	Left audio signal of voice guidance, and Voice Recognition (VR) prompts	Audio signal 0.004-0.04 V	If open: If voice activated, radio speakers buzz; if voice off, no effect. If short to ground: If voice activated, radio speakers buzz; if voice off, no effect.
6	BLU	MIC OUT (+) (Mic signal positive)	Microphone output signal positive	4-5 V (with TALK button pressed)	If open: No microphone signal shown in diagnostic screens: ‘‘Navi System Link'' and Functional Setup ‘‘Mic Level''. If short to ground: No microphone signal shown in diagnostic screens: ‘‘Navi System Link'' and Functional Setup ‘‘Mic Level''.
10	PUR	NAVI STRG SWITCH (Steering switches)	Steering switch output	4-5 V (Talk button depressed) 2.5-3 V (Back button depressed)	If open: Steering wheel ‘‘Talk‘‘, and ‘‘Back‘‘ switch/buttons do not work. If short to ground: Steering wheel ‘‘Talk'', and ‘‘Back'' switch/buttons do not work.
11	GRY	RG SHIELD GND (Shield route guidance)	Shield for terminal No. 5, 12	0 V	If open: No effect on voice output. If short to ground: No effect on voice output.
12	BLK	RG GND (Routs guidance ground)	Ground for voice guidance, and Voice Recognition (VR) prompts	0 V	If open: No effect on voice output. If short to ground: No effect on voice output.
13	GRY	MIC OUT SHIELD (Mic shield)	Shield for terminal No. 6, 14	0 V	If open: No effect on voice recognition. If short to ground: No effect on voice recognition.
14	PNK	MIC OUT (-) (Mic ground)	Ground for microphone signal	0 V	If open: No microphone signal shown in diagnostics: ‘‘Navi System Link'' and Functional Setup ‘‘Mic Level''. If short to ground: No effect on voice recognition.

Navigation Unit Inputs and Outputs for Connector C (8P)

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
1	WHT	+B BACK UP (+B Power source)	Continuous power source	Battery voltage	If open: Display picture goes out (display back light still on). NOTE: System will reboot to ‘‘enter code'' screen. If short to ground: Blows fuse No. 16 (15 A) in the under-hood fuse/relay box.
2	PUR	ACC RADIO (Accessory)	Power source for accessories	Battery voltage at ACC (I)	If open: Display picture goes out (display back light still on). NOTE: When re-connected the system will reboot to ‘‘enter code'' screen. If short to ground: Blows fuse No. 35 (7.5 A) in the under-dash fuse/relay box.
4	BLK	GND (Ground)	Ground for navigation unit	0 V	If open: No effect on system. If short to ground: No effect on system.
5	BRN	BACK LT- (Back light)	Reverse signal of select lever from backup light switch	In reverse, battery voltage: Otherwise 0 V	If open: Navigation never sees reverse. Diagnostic screen ‘‘Car Status'', ‘‘Back''=0. If short to ground: Blows fuse No. 10 (7.5 A) in the under-dash fuse/relay box.
6	BLU	VSP (Vehicle speed pulse)	Vehicle speed pulse signal from ECM	Pulses 0-5 V: Average 2.5 V, when moving	If open: No vehicle speed pulses. Diagnostic screen ‘‘Car Status'', VSP Navi=0. If short to ground: No vehicle speed pulses. Diagnostic screen ‘‘Car Status'', VSP Navi=0.
7	RED	DIAG + (Diagnostic positive)	Service check signal for navigation system	5-6 V	If open: No effect on system. If short to ground: System goes into diagnostic mode.
8	YEL	DIAG - (Diagnostic negative)	Ground for service check signal	0 V	If open: No effect on system. If short to ground: No effect on system.

Navigation Unit Inputs and Outputs for Connector D (2P)

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
1	———	GPS	GPS signal (5 V in, GPS signal out)	5 V	If open: GPS icon on screen is white, system links screen ANT shows ‘‘NG.'' If short to ground: Same as open.
2	———	GPS SH	Shield for terminal No. 1	0 V	If open: GPS icon on screen is white, system links screen ANT shows ‘‘NG.'' If short to ground: No effect on system.

Navigation Unit Inputs and Outputs for Connector E (3P)

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
1	———	RDS TMC	RDS TMC signal (5 V in, RDS-TMC siganal out)	———	If open: Poor traffic message cannel reception or interference. If short to ground: Same as open.
2	———	RDS TMC SHIELD	Shield for terminal No. 1	———	If open: Poor traffic message cannel reception or interference. If short to ground: No effect on system.

Navigation display Inputs and Outputs for 20P Connector

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
1	WHT	+B BACK UP (+B power source)	Continuous power source	Battery voltage	If open: Screen completely off (no backlight visible). If short to ground: Blows fuse No. 16 (15 A) in the under-hood fuse/relay box.
2	PUR	ACC RADIO (Accessory)	Power source for accessory	Battery voltage at ACC (I)	If open: Display and buttons do not work. If short to ground: Blows fuse No. 35 (7.5 A) in the under-dash fuse/relay box.
3	BLU	ECU BUS (+) (GA-NET)	Data bus (+) GA-Net	0-5 V pulses average 2.5 V depends on bus traffic	If open: Navigation buttons do not work. If short to ground: Navigation buttons do not work.
4	BRN	BUS (GA-NET) SHIELD GND	Shield for terminal No. 3, 13	0 V	If open: No change to display. If short to ground: No change to display.
5	GRN	ECU BUS (+) (GA-NET) (Display bus positive)	Data bus (+) GA-Net	0-5 V pulses average 2.5 V depends on bus traffic	If open: Navigation buttons do not work. If short to ground: Navigation buttons do not work.
6	GRN	SCTY RADIO	Security signal to rear screen	0 V	If open: If security system set, it will not trip when screen is removed. If short to gound: The security system set, it will not trip when screen is removed.
8	WHT	R SIG (Red signal)	Red color signal	0-1 V AC	If open: Red color missing (see ‘‘RGB Color'' diagnostic). If short to ground: Red color missing (see ‘‘RGB Color'' diagnostic).
9	RED	G SIG (Green signal)	Green color signal	0-1 V AC	If open: Green color missing (see ‘‘RGB Color'' diagnostic). If short to ground: Green color missing (see ‘‘RGB Color'' diagnostic).
10	BLK	GND (Ground)	Ground for display unit	0 V	If open: No change to display. If short to ground: No change to display.

Terminal Number	Wire Color	Terminal Name	Description	Voltage (about)	Symptom
11	GRY	ILL (+) (Illumination positive)	Parking light on signal from dash and console lights	Battery voltage if lights on: otherwise 0 V	If open: When brightness=‘‘Auto'', night mode for the display is inoperative when lights on. If short to ground: Blows fuse No. 14 (7.5 A) in passenger's under-dash fuse/relay box.
13	PNK	ECU BUS (-) (GA-NET)	Data bus (-) GA-Net	0-5 V pulses average 2.5 V depends on bus traffic	If open: Navigation buttons do not work. If short to ground: Navigation hard touch buttons work OK.
14	GRY	ECU BUS (GA-NET) SHIELD GND (Shield display bus)	Shield for display bus terminal No. 5, 15	0 V	If open: No change to display. If short to ground: No change to display.
15	RED	ECU BUS (-) (GA-NET) (Display bus negative)	Data bus (-) GA-Net	0-5 V pulses average 2.5 V depends on bus traffic	If open: Navigation buttons do not work. If short to ground: Navigation hard touch buttons work OK.
16	BRN	NAVI SCTY	Security signal from CD changer	0 V	If open: The security system set, it will not trip when screen is removed. If short to ground: If security system set, it will not trip when screen is removed.
17	GRN	GND SIG (Ground signal)	Ground for color signal	0 V	If open: No change to display. If short to ground: No change to display.
18	YEL	B SIG (Blue signal)	Blue color signal	0-1 V AC	If open: Blue color missing (see ‘‘RGB Color'' diagnostic). If short to ground: Blue color missing (see ‘‘RGB Color'' diagnostic).
19	BLK	C SIG (Composite signal)	Composite video (vertical/horizontal) synchronizing signal	0.3 V AC	If open: Picture rolls horizontally, colors still visible. If short to ground: Picture rolls horizontally, colors still visible.
20	GRY	SIG SHIELD GND (Shield signal)	Shield for terminal No. 8, 9, 17, 18, 19	0 V	If open: No change to display. If short to ground: No change to display.