GM Service Manual Online
For 1990-2009 cars only
Table 1: Radio Features
Table 2: Compact Disc Features
Table 3: XM Advisory Messages

The following list shows the radios available for this vehicle:

    • U1P - AM/FM, Internal single CD player, and RDS
    • UC6 - AM/FM, Internal six CD player, and RDS
    • U1A -Navigation Radio, remote six CD player, AM/FM, and RDS
    • UZ6 - Audio amplifier with 6 speakers (only available with UC6)

Radio Features

Controls

Base Radio U1P

Uplevel Radio UC6

Navigation Radio U1A

Theft Deterrent

The Radio has an LED that blinks whenever the ignition is OFF and acts as a pseudo theft deterrent.

NA

Power

Push the PWR/VOL knob to turn the radio on.

Volume

The volume is adjusted by rotating the PWR/VOL knob.

Recall RCL

Alternates between radio station frequency and the time.

N/A

Changing BandsAM/FM

Pressing the AM FM button switches between AM, FM1, and FM2.

Pressing the BAND button switches between AM, FM1, and FM2.

Tune

Turning the knob will choose radio stations.

Use the control pad located in the lower left corner to choose radio stations.

Seek

Pressing the SEEK button will tune to the next or previous station

Scan

Pressing the SCAN button for 2 seconds and the radio will scan to the next station, pause, and then continue to scan.

Pressing the SCAN button for more than 4 seconds and the radio will scan to the first preset station, pause, and then continue to scan the preset stations.

Pressing the SEEK button for more than 4 seconds and the radio will scan to the first preset station, pause, and then continue to scan the preset stations.

Preset Saving

Tune in station and press the EQ button to select desired equalization then press one of the six numbered pushbuttons until a beep is heard

Tune in station and press the AUTO EQ button to select desired equalization, then press one of the six numbered pushbuttons until a beep is heard

Tune in station and press one of the six numbered pushbuttons until a beep is heard

Tone

Press and release the TONE button until BASS, MID, or TREB appears. Turn the SELECT knob to increase or decrease

Press the AUDIO knob until BASS, MID, or TREB appears. Turn the AUDIO knob to increase or decrease.

Press the musical note button to access the audio menu and use the control pad located in the lower left corner.

Fade or Balance

Press and release the BAL FADE button until BAL or FADE appears.

Turn the SELECT knob to change the front/back or left/right settings.

Press the AUDIO knob until BAL or FAD appears.

Turn the AUDIO knob to change the front/back or left/right settings.

Press the musical note button to access the audio display.

Select next page to access fade or balance.

Use the control pad located in the lower left corner to adjust front/back or left/right settings.

Equalization

Adjust the TONE button and SELECT knob to create desired equalization.

Press and hold the EQ button for 2 seconds.

Press EQ or turn select knob to select desired EQ number.

Press and hold EQ button until a beep is heard.

Press the AUTO EQ button to choose between bass, midrange, or treble.

Press and hold the EQ button until CUSTOM appears then manually adjust using the AUDIO knob

Press EQ or turn select knob to select desired EQ number.

Press and hold EQ button until a beep is heard.

Press the musical note button to access the audio menu and select desired equalization.

Time Setting

Press and hold the HR or MN button until the time begins to change. The time can be set by tapping each button to incrementally adjust the time. Holding down each button will rapidly change the time.

To synchronize the time with an FM station, press and hold the HR and MN buttons at the same time until TIME UPDATED appears on the display.

Press the SETUP button to access the setup menu. Select CLOCK and adjust the time.

Program Type

Press the PROG TYPE to turn PTY on or off

Use the SELECT knob to select program type.

Pressing and holding the PROG TYPE button until a beep is heard will enable the interrupt feature. This feature will interrupt the CD player when the PROG TYPE selected is detected.

Press the P-TYPE button to turn PTY on or off

Use the P-TYPE knob to select program type.

Pressing and holding the P--TYPE button until a beep is heard will enable the interrupt feature. This feature will interrupt the CD player when the PROG TYPE selected is detected.

Press the BAND button to display the audio screen.

Press the control pad located in the lower left corner to select the RDS menu.

Select PTY and then the PTY type.

Radio Data System (RDS)

When INFO appears in the display, pressing the INFO button will display the message.

Pressing the TRAF button will cause the radio to seek a station that broadcasts traffic announcements. NO TRAF will be displayed if no station is found.

Press the BAND button to display to enter the FM screen.

Press the control pad located in the lower left corner to select the RDS menu.

Alternate Frequency

Press and hold the AM FM button for two seconds. AF ON will appear in the display. The radio may switch to a stronger station with the same programming.

Press and hold the AM FM button again for two seconds to turn AF off.

Press the BAND button to enter an FM screen.

Press the control pad located in the lower left corner to select the RDS menu and then select alternate frequency.

Speed Compensated Volume

N/A

Press the musical note button to access the audio screen.

Select next page to adjust SCV volume.

Compact Disc Features

Controls

Base Radio U1P

Uplevel Radio UC6

Navigation Radio U1A

Load disc into single CD player

Insert CD into player.

N/A

Insert CD into player.

Loading discs into a multiple disc CD changer

N/A

Press and hold the LOAD side of the LOAD CD button for two seconds.

The light located to the right of the slot will flash and then turn green.

Insert one CD.

Wait until light stops flashing and turns green then insert the next disc.

Up to 6 Discs can be inserted using the same method.

After the last disc has been inserted, press the load side of the LOAD CD button to cancel the load mode.

Open the changer door and remove the cartridge

Place the discs into the cartridge and load into changer.

Close the changer door.

Eject -- single Disc CD player

Press the EJECT button next to the CD player.

N/A

Press the EJECT button next to the CD player.

Eject -- Discs in a multiple Disc changer

N/A

Press the CD eject button once to eject the current Disc.

Press the CD eject button and hold for 2 seconds to eject multiple Discs.

Press the PWR off then on to cancel multiple ejections.

To eject the cartridge, open the changer door.

Fast Forward

Press and hold the right arrow button to fast forward within the selected track.

Reverse

Press and hold the left arrow button to reverse quickly within the selected track

Next/Previous track

Press the SEEK/SCAN button.

Press the SEEK button.

Track Scan

Press the SCAN button for more than 2 seconds to play a 10 second sample of every track.

Press and hold the SEEK button for more than 2 seconds to play a 10 second sample of every track.

Random

Press RDM3 button and the player will play the tracks in random order.

Press RDM button and the player will play the tracks in random order.

Pressing and holding the RDM button for more than 2 seconds will cause the changer to play random tracks on random discs.

Repeat

N/A

Press and release the RPT button once to repeat the current track

Press and hold the RPT button for more than 2 seconds to repeat the current Disc.

Press the Repeat button to repeat the current track.

Elapsed time

Press the RCL button to display how long the current track has been playing.

Pressing and holding this button until the display flashes will alternate the display between track number and elapsed time.

N/A

Song List

N/A

Select desired Disc.

Select the desired track and press and hold the SONG LIST button for more than 2 seconds. Repeat for every track to be saved.

N/A

Radio Reception

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:

    • The power output (wattage) of the broadcasting station
    • The location of the vehicle (or receiver) relative to the broadcast tower.
    • Obstacles between the tower and the receiver
    • Atmospheric conditions
    • What band (AM or FM) the station is broadcasting
    • Type of antenna and the ground plane

AM Reception

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

    • Bend around Obstacles
    • Follow the curvature of the earth
    • May reflect off the ionosphere (skip)

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:

    • Reflect off obstacles
    • Are absorbed by the ground
    • Penetrate the ionosphere

Broadcasts in the FM band are limited to "line of sight" reception which is typically 40 km (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:

    • Height of the broadcast antenna
    • Height of the receiving antenna
    • Terrain and buildings in the broadcast path

XM Reception

XM satellite radio provides digital radio reception. The XM signal is a broadcast from two satellites and, where necessary, terrestrial repeaters. The high power satellites allow the antenna to receive the XM signal even when foliage and other partial obstructions block the antennas view of the satellites. Terrestrial repeaters are used in dense urban areas. These repeaters will receive the satellite signal and re-broadcast them at much higher power levels in order to ensure reception in areas with densely packed tall buildings.

Audio Amplifier -- UZ6

The radio, digital radio receiver, or the CD changer supplies low level audio signals to the audio amplifier in order to boost the signal sent to the speakers.

The radio uses the antenna input signal to create a stereo audio output signal, which is sent at the user-defined volume level to the audio amplifier. The audio amplifier amplifies the signal and sends it to the appropriate speakers. Tone, balance and fade information is sent by the radio to the audio amplifier via a control circuit.

Remote Playback Device -- U1A

The radio controls and communicates with the remote playback device via the control circuit.

Remote CD Changer

The remote CD changer allows for multiple compact discs to be played continuously without having to manually change compact discs. Normal size discs may be played using the slots supplied in the magazine. The magazine must first be loaded with discs before it can played. To load CDs, insert the CDs from top to bottom, placing the discs in the magazine label side up. If a disc is loaded label side down, the disc will not play and an error will occur. Care should be used to align and insert the disc into one disc tray only. Repeat this procedure for loading all of the discs in the magazine. Once the discs are loaded into the magazine, open the door on the changer and push the magazine into the changer in the direction of the arrow marked on the magazine and close the door. When the CD magazine is loaded, the changer will begin checking for discs in the magazine. This will continue for up to one and a half minutes, depending on the number of discs loaded. To eject the magazine from the player, slide the CD changer door open. NOTICE: If the CD magazine fails to eject after the door is opened, do not attempt to pry the magazine from the CD changer. Whenever a CD magazine with discs is loaded in the changer, the CD changer symbol will appear on the radio display.

Radio Data System (RDS)

All three 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:

    • RDS functions are provided in the FM broadcast band only.
    • RDS functions will only work with FM broadcast stations that are broadcasting RDS data.
    • Not all FM Broadcast stations broadcast RDS data or offer all of the RDS services.
    • RDS functions may not work properly when reception is weak, reception is of poor quality, or RDS is not implemented properly by the FM Broadcaster.

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:

    • The name of the station
    • The type of program
    • General information such as artist and song title, call in phone numbers, etc.

Finding an RDS Station

To find an RDS station press the RDS button. The radio will seek to the next RDS station.

XM Satellite Radio

XM is a national satellite radio service that offers up to 100 coast to coast channels including music, news, sports, talk and children's programming. XM provides digital quality audio and text information, including song title and artist name. A service fee is required in order to receive the XM service. For more information, contact XM at www.xmradio.com or call 1-800-852-9696.

Digital Radio Receiver

The radio controls communicate with the digital radio receiver via the class 2 communication circuit. The digital radio receiver sends remote radio audio signals to the radio.

Viewing Messages

Press the DISP or RCL button while in XM mode to view various pieces of information related to the current song or channel. By pressing and releasing the DISP or RCL button, you may view four different categories of information: Artist Name/Feature, Song/Program Title, Channel Category, and other Additional Information that may be broadcast on that channel. Additional Information messages may not always be available. If an Additional Information message is being broadcast on the tuned channel, the INFO icon will appear on the display. Each of the four information types may have multiple pages of text. To reach a category, press and release the DISP or RCL button consecutively until the desired type is displayed. If there are multiple pages of text for the selected information type, the radio will automatically display all the pages for that type at a rate of approximately one page every three seconds before timing out and returning to the default display. You may override this feature by pressing the DISP or RCL button to review all of the pages at your own pace.

XM Advisory Messages

Radio Display Message

Condition

Updating

Updating encryption code

No Signal

Loss of signal

Loading XM

Acquiring channel audio (after 4 second delay)

CH Off Air

Channel not in service

CH Unavail

Channel no longer available

No Info

Artist Name/Feature not available

No Info

Song/Program Title not available

No Info

Category name not available

Not Found

No channel available for the chosen category

No Info

No text/informational message available

XM Locked

Theft Lock active

Radio ID

Electronic serial number (ESN) channel 0

Unknown

Radio ID not known (should only be if hardware failure

Chk XMRcvr

Hardware failure