GM Service Manual Online
For 1990-2009 cars only

Setting the Clock

Press HRS until the correct hour appears. Press and hold MIN until the correct minute appears.

You may set the clock with the ignition off if you press RECALL first and follow the same procedure described above.

Playing the Radio

VOLUME: This knob turns the system on and off and controls the volume. To increase the volume and turn the radio on, turn the knob clockwise. Turn it counterclockwise to decrease the volume.

RECALL: Press the upper knob briefly to recall the station being played or to display the clock. To change what is normally shown on the display (station or time), press the knob until you see the display you want, then hold the knob until the display flashes. If you press the knob when the ignition is off, the clock will show for a few seconds.

Finding a Station

AM-FM: Press the AM-FM button to switch between AM, FM1 and FM2. The display shows the selection.

TUNE: Turn the lower knob to choose radio stations.

SEEK: Press the right or left arrow to go to the next higher or lower station and stay there. The sound will mute while seeking.

SCAN: Press on of the SEEK arrows for two seconds, and SCAN will appear on the display. Use SCAN to listen to stations for a few seconds. The radio will go to a station, stop for a few seconds, then go on to the next station. Press one of the SEEK arrows again to stop scanning. The sound will mute while scanning.

PUSHBUTTONS: The six numbered pushbuttons let you return to the customer's favorite stations. You can set up to 18 stations (six AM, six FM1 and six FM2). Perform the following steps:

  1. Turn the radio on.
  2. Press the AM-FM button to select the band.
  3. Tune in the desired station.
  4. Press and hold one of the six numbered buttons. The sound will beep. When it returns, release the button. Whenever you press that numbered button, the station you set will return.
  5. Repeat the steps for each pushbutton.

P SCAN: Press this button to listen to each of the preset stations for a few seconds. The radio will go to the first preset station, stop for a few seconds, then go on to the next preset stations. Press P SCAN again to stop scanning. The radio will not stop at a preset station if the station is weak.

Setting the Tone

BASS: Press this knob lightly so it extends. Turn the knob to increase or decrease bass.

TREB: Press this knob lightly so it extends. Turn the knob to increase or decrease treble. If a station is weak or noisy, you may want to decrease the treble.

Push these knobs back into their stored positions when you are not using them.

Adjusting the Speakers (Base Radio)

BAL: Turn the control behind the upper knob to move the sound tot he left or right speakers. The middle position balances the sound between the speakers.

FADE: Turn the control behind the lower knob to move the sound to the front or rear speakers. The middle position balances the sound between the speakers.

BAL Control (Uplevel Radio)

Push the BAL Control knob to release it. Rotate the knob to move sound between the right and left speakers. Push the knob back in to store it when not adjusting.

FADE Control (Uplevel Radio)

Push the FADE Control knob to release it. Rotate the knob to move sound between the front and the rear speakers. Push the knob back in to store it when not adjusting.

TUNE Control (Uplevel Radio)

Push the TUNE Control knob to release it. Rotate the knob to choose desired radio stations. Push the knob back in to store it when not adjusting.

AUTO TONE Control (Uplevel Radio)

Press AUTO TONE to choose preset treble and bass equalization settings designed for one of the following:

    • ROCK
    • NEWS
    • POP
    • CLASSICAL
    • JAZZ
    • MAN

Each time AUTO TONE is pressed, another setting will appear on the display. When MAN (manual) appears the control of the tone will be back to the treble and bass knobs.

Playing a Cassette Tape

The longer side with the tape visible should face to the right. If the ignition and the radio are on, the tape can be inserted and will begin playing. If you hear nothing or hear a garbled sound, the tape may not be in squarely. Press EJECT to remove the tape and start over.

While the tape is playing, use the VOLUME, FADE, BAL, BASS and TREB controls just as you do for the radio. Other controls may have different functions when a tape is inserted. The display will show an arrow to show which side of the tape is playing.

If you want to insert a tape when the ignition or radio is off, first press EJECT or RECALL. Note that the cassette tape adapter kits for portable compact disc players will work in the cassette tape player.

The tape bias is set automatically.

If E on the radio display, the tape won't play because of an error.

    • E10: The tape is tight and the player can not turn the tape hubs. Remove the tape. Hold the tape with the open end down and try to turn the right hub counterclockwise with a pencil. Turn the tape over and repeat. If the hubs do not turn easily, the tape may be damaged and should not be used in the player. Try a new tape to make sure the player is working properly.
    • E11: The tape is broken. Try a new tape.

PREV (1): Press this button to search for the previous selection on the tape. The tape must have at least three seconds of silence between each selection for PREV to work. The sound will mute while seeking.

NEXT (2): Press this button to search for the next selection on the tape. The tape must have at least three seconds of silence between each selection for the NEXT to work. The sound will mute while seeking.

The SEEK left and right arrows will also find the previous and next selections on the tape.

(3): Press this button to reverse the tape rapidly. Press it again to return to playing speed. The radio will play while the tape reverses.

>> (4): Press this button to advance quickly to another part of the tape. Press the button again to return to playing speed. The radio will play while the tape advances.

SIDE (5) Press this button to change the side of the tape that is playing.

DOLBY (6) Press this button to reduce the background noise. The display will show either OFF of ON for a few seconds when you press the button.

Dolby® Noise Reduction is manufactured under a license from Dolby Laboratories Licensing Corporation. Dolby and the double-D symbol are trademarks of Dolby Laboratories Licensing Corporation.

EJECT: Press this button to remove the tape. The radio will play. If you leave a cassette tape in the player while listening to the radio, it may become warm.

CLN: If this message appears on the display, the cassette tape player needs to be cleaned. It will still play tapes, but you should clean it as soon as possible to prevent damage to the tapes and player. Refer to Tape Player and Cassette Care in this section. After you clean the player, press and hold EJECT for five seconds to reset the CLN indicator. The radio will display - - - to show the indicator was reset.

Find a Station

AUTO SET (Uplevel Radio) Press this button and the system will seek and set the 12 stronger FM or the 6 strongest AM stations on the preset buttons (depending on which band (AM or FM) you are listening to). AUTO SET will flash while seeking and will remain on until this function is complete. To return to the stations you manually set, press AUTO SET again.

Setting the TONE (Uplevel Radio)

BASS: Press this knob lightly so it extends. Turn the knob to increase or decrease bass.

TREB: Press this knob lightly is it extends. Turn the knob to increase or decrease the treble.

Push these knobs back into their stored positions when you are not using them.

TONE: This feature allows you to choose preset bass and treble, equalization settings designed for classical, pop, rock, jazz, talk and country/western stations. CLASS will appear on the display when you first press TONE. Each time you press it, another setting will appear on the display. Press it again after C W appears and MANUAL will appear. Tone control, will return tot he BASS and TREB knobs. Also, if you use the BASS and TREB knobs, control will return to them and MANUAL will appear.

Theft Deterrent Feature

The radio has this feature if it shows THEFTLOCK on its face. THEFTLOCK® is designed to discourage theft of the radio. It works by using a secret code to disable all radio functions whenever battery power is removed.

If THEFTLOCK® is active, the THEFTLOCK® indicator will flash when the ignition if OFF.

The THEFTLOCK® feature for the radio may be used or ignored. If ignored, the system plays normally and the radio is not protected by the feature. If THEFTLOCK® is activated, the radio will not operate if stolen.

When THEFTLOCK® is activated, the radio will display LOC to indicate a locked condition anytime the battery power is removed. If the battery loses power for any reason, you must unlock the radio with the secret code before it will operate.

Activating the Theft Deterrent Feature

The instructions which follow explain how to enter a secret code to activate the THEFTLOCK® system. It is recommended that you read through all nine steps before starting the procedure.

  1. Write down any 3 or 4 digit number from 000 to 1999 and keep it in a safe place separate from the vehicle.
  2. Important: If you allow more than 15 seconds to elapse between any of the steps, the radio display will automatically revert to time and you must start the procedure over at Step 4.

  3. Turn the ignition to the ACC or RUN position.
  4. Turn the radio off.
  5. Press the 1 and 4 buttons together. Hold them down until - - - shows on the display. Next you will use the secret code number which has been written down.
  6. Press MIN and 000 will appear on the display.
  7. Press MIN again to make the last 2 digits agree with the code.
  8. Press HR to make the first 1 or 2 digits agree with the code.
  9. Press AM-FM after you have confirmed that the code matches the secret code that was written down. The display will show REP to let you know that you need to repeat steps 5 through 7 to confirm the secret code.
  10. Press AM-FM and this time the display will show SEC to let you know that the radio is secure. The indicator by the volume control will begin flashing when the ignition is turned OFF.

Unlocking the Theft Deterrent Feature after a Power Loss

Enter the secret code as follows, pausing no more than 15 seconds between steps:

  1. LOC appears when the ignition is ON.
  2. Press MIN and 000 will appear on the display.
  3. Press MIN again to make the last 2 digits agree with the code.
  4. Press HR to make the first 1 or 2 digits agree with the code.
  5. Press AM-FM after you have confirmed that the code matches the secret code that was written down. The display will show SEC, indicating the radio is now operable and secure.

If you enter the wrong code 8 times, INOP will appear on the display. You will have to wait an hour with the ignition before you can try again. When you try again, you will only have 3 chances to enter the correct code before INOP appears.

Disabling the Theft Deterrent Feature

Enter the secret code as follows, pausing no more than 15 seconds between steps:

  1. Turn the ignition to the ACC or RUN position.
  2. Turn the radio off.
  3. Press the 1 and 4 buttons together, Hold them down until SEC shows on the display.
  4. Press MIN and 000 will appear on the display.
  5. Press MIN again to make the last 2 digits agree with the code.
  6. Press HR to make the first 1 or 2 digits agree with the code.
  7. Press AM-FM after you have confirmed that the code matches the secret code that was written down. The display will show - - -, indicating that the radio is no longer secured.

If the code entered is incorrect, SEC will appear on the display. The radio will remain secured until the correct code is entered.

When battery power is given to a secured radio, the radio will not turn on and LOC will appear on the display.

Removing the Customers Code

Important: Either the customers code or the factory backup code can be used in order to remove the customers code.

Perform the following steps in order to remove the customers code:

  1. Turn the ignition to the ACC or RUN position.
  2. Turn the radio OFF.
  3. Important: If the display changes to -- -- -- the theft deterrent is deactivated and no code is stored.

  4. Press and hold pushbuttons 1 and 4 for approximately 6 seconds until the display changes to SEC.
  5. Press the HR button.
  6. Set the first 2 digits (0-19) of the code with the HR button.
  7. Set the next 2 digits (0-99) of the code with the MIN button.
  8. Press the AM-FM button in order to enter the code.
  9. The theft deterrent is de-activated when -- -- -- is displayed and then the clock is displayed.

Adding the Customers Code

Perform the following steps in order to add the customers code:

  1. Turn the ignition to the ACC or RUN position.
  2. Turn the radio OFF.
  3. Important: If SEC is displayed the theft deterrent feature is already activated. Remove the old code before entering the new code.

  4. Press and hold the pushbuttons 1 and 4 for approximately 6 seconds until the display changes to -- -- --.
  5. Press the HR button.
  6. Set the first 2 digits (0-19) of the code with the HR button.
  7. Set the next 2 digits (0-99) with the MIN button.
  8. Press the AM-FM button in order to enter the code.
  9. Repeat steps 3-5 when REP then 00 are displayed. This will confirm the following:
  10. • The customers code
    • Activates the theft deterrent feature
    • After step 5, will display SEC in order to show the theft deterrent feature has been activated.

    Important: If -- -- -- is displayed after pressing the AM-FM button, the customers code has not been entered.

  11. Anytime the ignition is removed and the THEFTLOCK® is activated, the THEFTLOCK® light will flash once every 2 seconds. Anytime the battery power is cycled and the ignition is ON, the display will show LOC. The radio will then need to be unlocked by either the customers code or the factory backup code.

Obtaining the Radio Display Code (Scrambled Backup Code)

Perform the following steps in order to obtain the radio display code:

    Important: In order to display this code, the radio should be in the LOC mode or have SEC displayed before proceeding.

  1. Press and hold the pushbuttons 2 and 3 for approximately 6 seconds until the first 3 digits of the display code are displayed.
  2. Write the numbers down.
  3. Press the AM-FM button. The second 3 digits are displayed.
  4. Write the numbers down.

After approximately 5 seconds or if another button is pressed the display returns to LOC. The display code must be unscrambled in order to acquire the factory backup code that unlocks the radio.

In order to acquire the factory backup code call Delco Electronics Corporation and enter the authorized account number along with the display code that has been written down.

Changing the Customers Code

In order to change the customers code perform the following:

  1. Unlock the radio.
  2. Ensure there is no customer code currently stored in the radio.

In order to determine whether or not there is a customers code stored:

  1. Press and hold the pushbuttons 1 and 4 until the display changes.
  2. If SEC is displayed, there is a customers code stored. Remove the stored code. Refer to Removing the Customers Code. If -- -- -- is displayed there is no code stored and a new code can be added.

Obtaining the Factory Backup Code

If the customers code is unavailable, refer to the Dealer Communications System for the unlock procedures or call Technical Assistance.