Radio/Audio System Description and Operation d

The Entertainment System on this vehicle is configured with either a base or an uplevel system. Both the base and uplevel systems contain a radio, antenna, speakers, and on some vehicle lines an audio amplifier and/or rear seat audio (RSA).

The uplevel system differs from the base level system by providing the customer with enhanced audio system features. Some of those features may include the radio data system (RDS), extended range speakers, an audio amplifier (or an uplevel amplifier), rear seat audio (RSA), and video entertainment system.

The following list shows the radios available for this vehicle:

Each item in the list below represents topics covered in detail below.

Radio Signal

The radio signal is sent from a broadcast station and is then received by an antenna. The strength of the signal received depends on the following:

AM Reception

The AM band has a lower frequency range than the FM band. These longer wavelengths:

The AM frequencies have longer range due to the ground wave. The ground wave follows the curvature of the earth and is effected by its conductivity. Greater conductivity equates to less signal loss thus transmission over water is better than over land. The AM band has a range of 80-320 km (50-200 miles).

FM Reception

The shorter wavelengths of the higher frequency FM band:

Broadcasts in the FM band are limited to "line of sight" reception which is typically 40km (25 miles). Even when out of a direct line of sight, the signal may be reflected into areas that would be in a "shadow" otherwise. Factors which affect the line of sight include:

The antenna is comprised of a very thin metal grid which is permanently affixed to the top center of the windshield. If the antenna becomes damaged, the windshield must be replaced.

The audio amplifier is standard on some vehicle lines but is optional on most. The radio supplies low level audio signals to the audio amplifier in order to boost the signal sent to the speakers. The amplifier present signal circuit allows the radio to recognize that an amplifier is present. Once the radio detects an audio amplifier, it will output low level audio signals. The audio amplifier on this vehicle is turned on when it receives battery voltage from the radio (when the radio is turned on) via the amplifier control circuit.

The "Theftlock" theft deterrent system is a feature on all base and uplevel radios. There is no need to program a security code into the radio as in past model years. The theft deterrent system now utilizes class 2 serial data to determine if the radio is in the appropriate vehicle. Each time the radio receives the "run" power mode message, it compares the VIN information it has stored to the VIN information received from a module on the class 2 serial data circuit responsible for transmitting that information. If a mis-match occurs, the radio display will indicate to the user the radio is locked. Once this takes place, a DTC will set, the radio will not respond to any button presses and become inoperative. The two scenarios able to cause this condition are:

The only way to unlock the radio is by using a scan tool. Always refer to the table in this section to diagnose the "Theftlock" DTC for further information.

The Integral Multi Disc CD Changer has the capability of storing and playing up to six (6) compact discs. The Integral Multi Disc CD Changer has a shock-absorbing system. Only under extreme operating temperatures or severe shock or vibration should the compact disc player skip or mute. If the customer travels an abnormally rough road, a skip condition may be normal. Test drive the vehicle on a normal road with a known good CD. If the condition is still present, replace the radio.

The use of CD lens cleaner discs is not advised, due to the risk of contaminating the lens of the CD optics with lubricants internal to the CD mechanism.

Single Disc Loading

To operate the Integral Multi Disc CD Changer in the single play mode, press and release the LOAD button and wait for the LED to the right of the disc door to turn green. Load a disc when the LED turns green. If the radio is on, the disc will begin to play automatically. If the radio is off, press the LOAD button for the disc to play.

Multi Disc Loading

To operate the Multi Disc CD Changer in the multi disc mode, press and hold the LOAD button for two seconds. An audible beep will be heard and the LED to the right of the disc door begins to flash. The radio will also display the message "INSERT CD". When the LED stops flashing and turns green, load a disc. Once the disc is loaded the LED begins to flash again. The radio will also display the message "MULTI LOAD" to indicate the multi load mode has been initiated and the changer will begin accepting a disc for however many empty slots there may be. When the LED stops flashing and turns green, load another disc. Repeat this procedure to continue loading discs. The CD changer holds up to six discs.

When the changer is full (six discs are loaded) and the LOAD button is pressed, three audible beeps are heard and the message "CHANGER FULL" is displayed.

Removing CDs

Use the eject button (the button labeled CD) to remove a disc or discs.

Perform the following to eject:

Important:: Pressing the CD button repeatedly, causes the radio receiver's 25 second eject timer to reset at each press of the button. This will cause the receiver to not eject a disc until the 25 second time period has elapsed.

Song List Feature

The Multi Disc CD Changer has a feature called Song List. This feature is capable of saving 20 track selections to a play list.

To save tracks into Song List, perform the following :

1. The disc player must be on with at least one disc loaded.
2. The message "S-LIST" should not be displayed on the radio. If "S-LIST" is present, press the SONG LIST button to turn it off.
3. Select the desired disc by pressing the numbered pushbutton and then use the SEEK right arrow button to locate the track that you want to save. The track will begin to play.
4. Press and hold the SONG LIST button for two or more seconds to save the track into memory. When SONG LIST is pressed an audible beep is heard. After two seconds of pressing SONG LIST continually, two audible beeps will sound to confirm that the track has been saved.
5. Repeat steps 3 and 4 for saving other selections.

To play the Song List press the SONG LIST button. One beep is heard and "S-LIST" appears on the display. The recorded tracks will begin to play in the order that they were saved.

To delete tracks from the Song List.

1. The disc player must be on.
2. Press the SONG LIST button. The message "S-LIST" appears on the display.
3. Press the SEEK button to locate desired track to be deleted.
4. Press and hold the SONG LIST button for two seconds. After two seconds, two beeps are heard confirming that the track has been deleted.

To delete the entire Song List.

1. The disc player must be on.
2. Press the SONG LIST button. The message "S-LIST" appears on display.
3. Press the SEEK button to locate desired track to be deleted.
4. Press and hold the SONG LIST button for more than four seconds. After two seconds, a beep will be heard followed by two beeps and a final beep after four seconds. The message "S-LIST EMPTY" appears on the display.

The Rear Seat Audio (RSA) controller allows the rear seat passengers to listen to a different music source than the front seat passengers. For example, the rear seat passengers may listen to the cassette or CD through headphones while the driver listens to the radio through the front speakers. The rear seat passengers have control of the volume for each headphone. The primary radio controls always override the RSA controls.

Seek (SEEK)

Press the SEEK button in order to seek to the next higher or lower station. The sound will mute when seeking another frequency. The SEEK button is inactive when the front radio is in the SEEK mode.

Power (PWR)

Press the PWR push button in order to turn the rear seat audio system On or Off. The rear speakers mute when the power is turned On. The rear seat audio functions are operable even when the primary radio power is off.

Band Switching (AM/FM)

Press the AM/FM push button in order to select between (AM and FM) or (AM, FM1 and FM2) for radios with two FM bands. The selection appears on the display. If the front passengers are already listening to AM-FM, the rear seat audio controller will not switch between the bands and cannot change the frequency.

Source Switching (TAPE CD)

Press the TAPE CD push button in order to activate the source switching feature. There must be a cassette tape and/or compact disc in the player.

Preset Program (P.SET PROG)

Press the P.SET PROG button in order to select between pre-programmed station presets. The front passenger must be listening to something different for the P.SET PROG to operate.

Volume (VOL)

Rotate the volume control in order to increase or decrease the volume. The top VOL knob controls the top headphone and the bottom VOL knob controls the bottom headphone.

All uplevel audio systems are equipped with technology known as the Radio Data System (RDS). RDS is a system that sends data along with the audio of the FM station you are currently tuned to. RDS is a standard that defines how a FM broadcast station may send digital data along with the audio program. Think of it as a one way wireless modem, allowing the broadcaster to send information about his program to your receiver.

RDS data is carried in what is known as a "subcarrier". A subcarrier is a frequency that the FM broadcaster is authorized to use to send data or other audio programs that are not audible in the main audio program. RDS information can be used to display program information and to control the radio.

To receive the RDS signal, all that is needed is an FM receiver with a RDS circuit. A special integrated circuit capable of dealing with the RDS signal is in the RDS circuit and passes it along to the receiver's microprocessor where it is decoded and acted upon.

RDS Basic Information

RDS basic information:

In some cases, a radio station broadcasting incorrect information may cause the RDS features of the radio to appear to work improperly.

Broadcast RDS information can be used in a variety of ways by the receiver and listener, but basically falls into two categories: Display and Control.

Displaying Program Information

RDS displays textual information such as:

RDS is always on. When tuned to a non-RDS station, your radio will display frequency information as you would normally expect. When tuned to a RDS station, your radio will change from displaying the frequency of the FM station to displaying the call letters of the station or display the nickname of the station. This feature is known as the Program Service Name.

Controlling the Radio

RDS can control the radio when data the receiver can use responds to timely information and performs the following:

Viewing and Selecting RDS Program Type Information

The Program Type feature is activated by pressing the program type button (labeled PROG TYPE or P-TYPE). The program type name will be displayed (if the broadcaster is broadcasting one). The program type name is an eight-character name that the broadcaster may use to further identify the type of programming currently being broadcast. Turn the SELECT or P-TYPE knob to select the desired program type. If a station with the selected program type is not found, the radio displays "NOT FOUND".

RDS Program Type Interrupts

When the Program Type feature is on, all program types may be selected as interrupts. Perform the following to select a program type as an interrupt.

1. Turn ON the radio.
2. Select the program type.
3. Press and hold the program type button (labeled PROG TYPE or P-TYPE) for two seconds while the program type is displayed.

When an interrupt is set, the display shows the program type followed by an asterisk and the brackets around the [P-TYPE] icon are illuminated.

To turn an interrupt off:

1. Select a program type marked as an interrupt.
2. Press and hold the program type button (labeled PROG TYPE or P-TYPE) for two seconds. The program type will be unmarked by turning off the asterisk. If no other program type interrupts are set, the brackets around the [P-TYPE] icon are also turned off.

When a Program Type Interrupt is set, the radio will wait for the current FM RDS station to change its program type to one of those selected as an interrupt. When the station program type changes to a program type interrupt setting then the interrupt is activated. If the radio is in a playback mode, an interrupt will cause the radio to switch to the FM band, display the program type followed by "INT", and adjust the volume to the last active interrupt volume. If the radio is in the FM mode when an interrupt occurs, only the volume will change. The radio resumes the mode that was active prior to the interrupt, when an interrupt ends. An interrupt in progress may be canceled by pressing the program type button or a mode button.

During a national or local emergency, a special program type interrupt message "ALERT!" is displayed. This special announcement will cancel all other RDS features that are in progress, such as a traffic announcement.

Using the RDS Traffic Feature

Some RDS broadcasters may carry traffic information programming to inform you of current traffic conditions in your listening area and is indicated by the icon in the radio display. RDS enables the broadcaster to get this information to you even when you are listening to a tape or compact disc. This feature can be enabled or disabled by the listener. Press the TRAF button to find a station that claims to carry traffic information. You may do this even when playing a cassette tape or compact disc. This action will operate in the background without interrupting the current playback. If the radio is not currently tuned to an RDS traffic station, the radio will immediately SEEK an RDS traffic station. If the radio finds an RDS traffic station, the TRAF icon will appear in the radio display as will brackets around the [TRAF] icon. If the radio cannot find an RDS traffic station after searching through the entire FM band, the radio will display "NO TRAFFIC".

Alternate Frequency (AF) Switching

RDS permits broadcaster's to send information to the radio that allows the radio to automatically switch frequency to the best quality station in that broadcaster's network.

Since the radio is displaying the broadcaster call letters or nickname, the listener will not see the frequency during an AF switch unless you have changed the default display to be frequency instead of Program Service name.

To enable or disable AF switching, perform the following:

When AF is enabled and you recall a RDS station stored on preset, the radio determines if the station stored is of acceptable quality. If not, the radio checks all available AF's for your station. If the radio fails to locate your program, "AF SEARCH" will be displayed as the radio scans across the band looking for your program or an affiliated network. If the radio cannot find the original station or an acceptable alternate frequency "NOT FOUND" will be displayed and the radio returns to the original frequency for the preset.

RDS Clock Time

Broadcasters can choose to send clock time information in the RDS data. This information can be used to update the clock time on the radio. RDS clock time is broadcasted once a minute. To set the clock using RDS clock data perform the following:

The Steering Wheel Controls consist of multiple momentary contact switches that connect a series of resistors so that each switch selection corresponds to a fixed resistance value. These fixed resistance values allow the radio to identify which switch has been pressed .

The radio displays an error when any of the following occurs.