Entertainment System Buick Century VI

Fastener Tightening Specifications

Fastener Tightening Specifications

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Diagnostic Starting Point - Entertainment

Begin the system diagnosis by reviewing the Description and Operation section of this manual. Reviewing the Description and Operation information will help you determine the correct diagnostic procedure when a malfunction exists. This will also help you determine if the condition described by the customer is normal operation. Refer to SYMPTOMS - ENTERTAINMENT .

Symptoms - Entertainment

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the Radio/Audio System. Refer to «CHECKING AFTERMARKET ACCESSORIES»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__checking-aftermarket-accessories) in Wiring Systems.
2. Inspect for easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Radio Poor Reception»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system)
2. «Radio Display Inoperative»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system)
3. «Tape Player Weak, Slow, Or Garbled Output»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system)
4. «Steering Wheel Controls Inoperative»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system)
5. «SPEAKERS INOPERATIVE - One or More»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system__speakers-inoperative-one-or-more)
6. «Audio Too Loud at Low Settings»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system)

Audio System Troubleshooting Hints

Many conditions that affect radio operation may be corrected without removing the radio from the car. Verify the condition, and follow the diagnostic procedures in order to isolate and correct the condition. In order to properly diagnose any audio system problems, ensure that you have a fully charged battery.

Preliminary Inspection

Tools Required

J 39916-A CD and Cassette Diagnostic Audio Kit. See Special Tools and Equipment .

1. Inspect for any aftermarket equipment that may have been installed on the vehicle. If aftermarket equipment is found, disconnect the equipment and verify that the audio noise is still present.
2. Verify that the antenna connector and the antenna coaxial cable are clean and tight.
3. For reception concerns, first determine if the customer is within the listening area of the stations they are attempting to receive.
4. Stations at the lower end of the FM band are more susceptible to audio noises than stations at the higher end.
5. If the noise is only from one speaker, inspect for the following items before speaker replacement: Isolate the noise using the J 39916-A Inspect the speaker connections in order to ensure they are clean and tight. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__testing-for-intermittent-and-poor-connections) in Wiring Systems. Inspect for a loose or incorrectly installed speaker or surrounding trim. Loose trim may cause a buzz or flutter which sounds like a malfunctioning speaker.
6. Ignition noise on the FM band may be an indication of an ignition system problem.
7. Verify that all vehicle grounds are clean, tight, and free of corrosion.
8. Inspect the rear defogger grid lines for large breaks or dark spots.
9. Inspect the connections at the radio antenna module, if equipped, in order to ensure that they are clean and tight.
10. Compare the customers vehicle to another of similar model and audio system in order to determine if the condition is abnormal.

Identifying Concerns

1. In order to isolate the source of the noise/poor reception, identify the ignition switch position that the concern is most noticeable: 1.1. Turn the ignition switch to the accessory position. 1.2. Turn ON the radio. 1.3. Seek up 88 to 108 FM then 550 to 1600 AM. 1.4. Record the number of valid radio stations where the tuner stops. 1.5. Repeat these steps with the ignition ON, and the engine OFF, then repeat the steps again with the engine running.
2. Return the ignition switch to the position that the concern was most noticeable.
3. Remove the fuses or circuit breakers, one at a time, until the noise has been eliminated.
4. Identify what systems or components are powered by the fuse.
5. Reinstall all fuses and circuit breakers.
6. Disconnect the components powered by the fuse, one at a time, until the concern has been eliminated.

Corrective Action

1. Inspect the ground integrity of the component or system causing the noise.
2. Malfunctioning and marginal components such as relays and solenoids may cause noise and/or poor reception.
3. Always use a braided ground strap when applying additional grounds and keep the ground strap as short as possible.
4. If the noise source is found to be coming from the vehicle harness: Route the antenna cable separately from the wire harness that is emitting the noise. Use aluminum or nickel tape in order to shield the antenna cable. Try variations of the following repairs: Try adding only aluminum or nickel tape before adding a ground strap to the tape. Wrap a ground strap 360 degrees around the tape, securing the other end of the strap to chassis ground.

1. Capacitors work best on switch pops and low frequency noise.
2. Filters work best on high frequency whines and static.
3. After adding any suppression device, inspect all of the vehicle systems, including those not related to the audio system, for proper operation and function.
4. Whenever possible, make a test harness that includes filters or capacitors. Always inspect the effectiveness and operation before permanent installation.
5. If an audible pop is caused due to operating a switch, perform the following repairs as necessary: Add a capacitor across the contacts of the switch. Add a capacitor from the battery positive voltage (B+) side of the switch to chassis ground. Add a capacitor from the ground side of the switch to chassis ground.
6. Use the following available noise suppression devices: 220 micro farad (50V) capacitor GM P/N 1227895 This works well for ignition system related noise. 0.47 micro farad capacitor GM P/N 1227894 This works well for switches and relays. Feed through capacitor GM P/N 477371 This works well for high current situations. Filter package GM P/N 1224205 This works well for low current situations. Fuel pump suppressor GM P/N 25027405 21 inch braided ground strap GM P/N 8910791 19 inch braided ground strap GM P/N 6286800 10.5 inch braided ground strap GM P/N 6287160 8.5 inch braided ground strap GM P/N 12091511

Generator Whine Concerns

1. Inspect the ground terminal and cable for high resistance.
2. Inspect the generator and brackets for loose or coated mounting bolts.
3. Verify that the ground straps between the engine and the frame are clean and tight.
4. If the noise is still present, inspect the charging system for proper operation. Refer to «DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL»(/buick/century/vi-1997-2005/remont/body-electrical/#battery) in Battery.
5. Install a filter GM P/N 1224205 in the battery voltage feed circuit to the radio.
6. If the noise is not eliminated, install the filter in each following variation: Install the filter with the single wire side toward the radio and the ground wire attached to chassis ground. Remove the ground to the filter. Reverse the filter so that the two-wire side is toward the radio with the ground wire attached to chassis ground. Remove the ground from the filter.
7. If the filter GM P/N 1224205 causes a delay when turning the radio ON or OFF, or other problems, remove the filter and Install a 0.47 micro farad capacitor to chassis ground.
8. Before reassembling the vehicle, remove any unneeded filters.
9. Test the functionality of all the vehicle systems, including those not related to the audio system, for proper operation and function.

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Speakers Inoperative - One or More

Schematic Reference: Radio/Audio System Schematics

All Speakers Inoperative

With RPO UX7 or UQ3

1. Speaker output shorted - Test all speaker outputs for a short. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
2. Defective radio - Replace radio. Refer to «RADIO REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

With RPO U85

1. Battery positive voltage circuit to the amplifier open. Test the battery positive voltage circuit to the amplifier for an open. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
2. No level audio signal circuit shorted. Test all low level audio signal circuits for a short to ground or short to voltage. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
3. No low level audio output from the radio. Test for any AC voltage between the left front low level audio signal circuits at the amplifier harness connector, disconnected with the radio volume adjusted to 50 percent. If no AC voltage is present, replace the radio. Refer to «RADIO REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .
4. No audio output from the amplifier. Replace the amplifier. Refer to «AMPLIFIER REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

One Speaker Inoperative

1. Speaker output open. Test the appropriate speaker output circuits for an open. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
2. No audio output from the radio. Test for any AC voltage between the appropriate speaker output circuits at the speaker harness connector, disconnected with the radio volume adjusted to 50 percent. If AC voltage is present, replace the speaker. Refer to «Speaker Replacement Reference»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) . If no AC voltage is present, replace the radio. Refer to «RADIO REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

1. Speaker output circuit from amplifier open or shorted. Test the appropriate speaker output circuits for an open or short. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
2. Low level audio circuit open. Test the appropriate low level audio circuit for an open. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
3. No low level audio output from the radio. Test for any AC voltage between the appropriate low level audio signal circuits at the amplifier harness connector, disconnected with the radio volume adjusted to 50 percent. If no AC voltage is present, replace the radio. Refer to «RADIO REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .
4. No audio output from the amplifier. Test for any AC voltage between the appropriate speaker output circuits at the speaker harness connector, disconnected with the radio volume adjusted to 50 percent. If AC voltage is present, replace the speaker. Refer to «Speaker Replacement Reference»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) . If no AC voltage is present, replace the amplifier. Refer to «AMPLIFIER REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

Speaker(s) - Reduced Volume/Audio Distortion

1. Speaker output circuit high resistance. Test the appropriate speaker output circuits for high resistance. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
2. Defective speaker - Replace the appropriate speaker. Refer to «Speaker Replacement Reference»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

1. Speaker output circuit high resistance. Test the appropriate speaker output circuits for high resistance. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
2. Amplifier present signal circuit shorted to ground. Test the amplifier present signal circuit for a short to ground. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
3. Low level audio circuit open. Test the appropriate low level audio circuit for an open. Refer to «CIRCUIT TESTING»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__circuit-testing) and «WIRING REPAIRS»(/buick/century/vi-1997-2005/remont/body-electrical/#wiring-systems__wiring-repairs) in Wiring Systems.
4. Defective speaker - Replace the appropriate speaker. Refer to «Speaker Replacement Reference»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

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1. Remove the instrument panel (I/P) cluster trim plate. Refer to TRIM PLATE BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER in Instrument Panel, Gages, and Console.
2. Remove the radio screws.
3. Disconnect the electrical connector and the coaxial cable connector from the radio.
4. Remove the radio from the I/P.

Scheme 40

1. Connect the electrical connector and the coaxial cable connector to the radio.
2. Install the radio to the I/P. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the radio screws. Tighten Tighten the screws to 2 N.m (18 lb in).
4. Install the cluster trim plate. Refer to TRIM PLATE BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER in Instrument Panel, Gages, and Console.

Scheme 41

1. Remove the rear shelf trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
2. Remove the rear seat sound barrier. Refer to SOUND BARRIER REPLACEMENT - REAR SEAT BACK in Interior Trim.
3. Disconnect the electrical connector from the low frequency audio amplifier.
4. Loosen the nuts on the low frequency audio amplifier.
5. Move the low frequency audio amplifier to the right and down.
6. Remove the low frequency audio amplifier from the rear shelf.

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1. Align the studs to the rear window panel slots and slide into place. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Tighten the low frequency audio amplifier nuts. Tighten Tighten the low frequency audio amplifier nuts to 6 N.m (53 lb in).
3. Connect the electrical connectors to the low frequency audio amplifier.
4. Install the rear seat sound barrier. Refer to SOUND BARRIER REPLACEMENT - REAR SEAT BACK in Interior Trim.
5. Install the rear shelf trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.

Cassette Player Care and Cleaning

Tools Required

J 39916-A CD and Cassette Diagnostic Audio Kit. See Special Tools and Equipment .

Follow the recommended cleaning schedule

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1. Clean the cassette player every 15 hours for the best performance.
2. Clean the cassette player every 50 hours in order to prevent damage to the tape head. Clean the following 2 parts on the tape player
3. The head
4. The capstan Leave the tape player in the vehicle, since you can reach the parts through the tape door. Perform this service at least every 50 hours of cassette operation. After 50 hours of tape play, CLN (Clean) appears on the display as a reminder. Although the system will still function when this message is displayed, the following conditions may occur until the head and the capstan are cleaned
5. Reduced sound quality
6. Damage to the cassette tapes After cleaning the cassette tape player, press and hold EJECT for 5 seconds in order to reset the CLN indicator. The radio displays - in order to show that the clean feature has been reset. Failure to clean the cassette player regularly may cause the following conditions
7. Reduced sound quality
8. Damage to the cassettes
9. Damage to the mechanism Keep the cassette tapes correctly stored in their plastic cases away from the following conditions
10. Contaminants
11. Direct sunlight
12. Extreme heat Failure to correctly store the cassette tapes may cause the following conditions
13. Improper operation of the cassette tapes
14. Premature failure of the tape player The cassettes are subject to wear. The sound quality may degrade over time. Before servicing a tape player, verify that the following conditions exist
15. The cassette tape is in good condition.
16. The tape player is clean. Clean the tape player at least after every 50 hours of use in order to provide optimum performance. The radio displays CLN as a reminder every 50 hours. If a reduction in the sound quality occurs, regardless of when the tape player was last cleaned, play a different cassette tape in order to see if the tape or the tape player is at fault. If the second cassette tape results in no improvement in sound quality, clean the tape player. Use a scrubbing action, non-abrasive cleaning cassette, part of J 39916-A , for proper tape player cleaning. This cleaner is a wet-type cleaning system. The wet-type cleaning system uses a cleaning cassette with pads. The pads scrub the tape head as the hubs of the cleaner cassette turn. If you use this type of cleaner, the following conditions may occur
17. The radio displays an error.
18. The cartridge ejects. These conditions are normal and is the result of an added feature in the tape player that detects broken tapes. If an error occurs, insert the cleaning cassette at least 3 times in order to thoroughly clean the tape player. You can also use a non-scrubbing action, wet-type cleaner. This type of cleaner uses a cassette with a fabric belt which cleans the tape head. This type of cleaning cassette will not cause an error, but may not clean the tape player as thoroughly as the scrubbing type cleaner.

Scheme 44

1. Remove the rear shelf trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
2. Loosen the rear of the headliner. Refer to HEADLINER REPLACEMENT in Interior Trim.
3. Disconnect the rear window antenna lead from the rear window antenna connector.
4. Remove the antenna module bolt.
5. Disconnect the antenna module electrical connector.
6. Disconnect the antenna coaxial cable.
7. Remove the antenna module.

Scheme 45

1. Install the antenna module.
2. Connect the antenna coaxial cable to the antenna module.
3. Connect the antenna module electrical connector. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the antenna module bolt. Tighten Tighten the bolt to 3 N.m (27 lb in).
5. Connect the antenna lead to the rear window antenna connector.
6. With tape, secure the wiring harnesses to the inner upper panel of the rear window.
7. Install the headliner. Refer to HEADLINER REPLACEMENT in Interior Trim.
8. Install the rear shelf trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.

Removal Procedure

Note. Use tape on the tool surface so that you do not damage the paint on the antenna mast.

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1. Unscrew the antenna mast.
2. Remove the antenna mast from the antenna base.

Installation Procedure

Note. Use tape on the tool surface so that you do not damage the paint on the antenna mast.

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1. Install the antenna mast to the antenna base. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Screw the antenna mast to the antenna base. Tighten Tighten the antenna mast to 5 N.m (44 lb in).

Tools Required

J 38536-A Antenna Bezel Socket. See Special Tools and Equipment .

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1. Remove the fixed antenna mast. Refer to «FIXED ANTENNA MAST REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .
2. Open the rear compartment.
3. Reposition the right side rear compartment trim. Refer to COMPARTMENT TRIM PANEL REPLACEMENT - REAR in Body Rear End.
4. Remove the fixed antenna bezel retaining nut using J 38536-A .
5. Remove the fixed antenna bezel.
6. Remove the fixed antenna from the quarter panel.
7. Disconnect the fixed antenna extension cable from the fixed antenna.

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1. Position the fixed antenna to the quarter panel.
2. Install the antenna bezel to the fixed antenna.
3. Loosely install the antenna bezel retaining nut.
4. Connect the antenna extension cable to the fixed antenna. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
5. Install the fixed antenna bezel retaining nut using J38536-A . Tighten Tighten the antenna bezel retaining nut to 10 N.m (89 lb in).
6. Reposition the right side rear compartment trim. Refer to COMPARTMENT TRIM PANEL REPLACEMENT - REAR in Body Rear End.
7. Close the rear compartment.
8. Install the fixed antenna mast. Refer to «FIXED ANTENNA MAST REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .

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1. Remove the right instrument panel (I/P) insulator. Refer to CLOSEOUT/INSULATOR PANEL REPLACEMENT - RIGHT in Instrument Panel, Gages and Console.
2. Pull back the right side of the carpet in order to gain access to the wiring harness.
3. Disconnect the I/P antenna extension cable from the body harness antenna cable.
4. Remove the I/P compartment. Refer to COMPARTMENT REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages and Console.
5. Remove the radio. Refer to «RADIO REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .
6. Observe the routing of the I/P antenna extension cable. Cut off the visible ends of the I/P antenna extension cable being replaced: Cut off the radio end of the extension cable. Cut off the end of the cable that connects at the front door hinge pillar. Cut the cable at the location where the cable exits the I/P wiring harness, as shown.

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1. Install the antenna extension cable as noted before removal. IMPORTANT: Ensure that the cable is secured to the harness at least every 150 mm (6 in) to aid in protecting and routing the cable.
2. Use electrical tape in order to secure the extension cable along the outside of the wiring harness.
3. Connect the I/P antenna extension cable to the radio. Install the radio. Refer to «RADIO REPLACEMENT»(/buick/century/vi-1997-2005/remont/entertainment-systems/#entertainment-system) .
4. Connect the I/P antenna extension cable to the body harness antenna cable along the front door hinge pillar.
5. Install the I/P compartment. Refer to COMPARTMENT REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages and Console.
6. Install the right I/P insulator. Refer to CLOSEOUT/INSULATOR PANEL REPLACEMENT - RIGHT in Instrument Panel, Gages and Console.
7. Install the right carpet.

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1. Remove the right upper quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER UPPER in Interior Trim.
2. Disconnect the body harness antenna extension cable from the antenna cable.
3. Remove the rear seat cushion. Refer to SEAT CUSHION REPLACEMENT - REAR in Seats.
4. Remove the right instrument panel (I/P) insulator. Refer to CLOSEOUT/INSULATOR PANEL REPLACEMENT - RIGHT in Instrument Panel, Gages, and Console.
5. Remove the right front carpet retainer. Refer to CARPET RETAINER REPLACEMENT - FRONT in Interior Trim.
6. Remove the right rear carpet retainer. Refer to CARPET RETAINER REPLACEMENT - REAR in Interior Trim.
7. Remove the lower trim panel from the right center pillar.
8. Pull back the right side of the carpet in order to gain access to the wiring harness.
9. Disconnect the I/P antenna extension cable from the body harness antenna cable at the front door hinge pillar.
10. Observe the routing of the antenna cable. Cut off the visible ends of the body harness antenna cable to be replaced.

Scheme 62

Scheme 63

1. Install the antenna cable as noted before removal. IMPORTANT: Ensure that the cable is secured to the harness at least every 150 mm (6 in) to aid in protecting and routing the cables.
2. Use electrical tape in order to secure the extension cables along the outside of the wiring harness.
3. Connect the I/P antenna extension cable to the body harness antenna cable along the front door hinge pillar.
4. Install the right carpet.
5. Install the lower trim panel to the right center pillar.
6. Install the right rear carpet retainer. Refer to CARPET RETAINER REPLACEMENT - REAR in Interior Trim.
7. Install the right front carpet retainer. Refer to CARPET RETAINER REPLACEMENT - FRONT in Interior Trim.
8. Install the right I/P insulator. Refer to CLOSEOUT/INSULATOR PANEL REPLACEMENT - RIGHT in Instrument Panel, Gages, and Console.
9. Install the rear seat cushion. Refer to SEAT CUSHION REPLACEMENT - REAR in Seats.
10. Connect the antenna extension cable to the body harness antenna cable.
11. Install the right upper quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER UPPER in Interior Trim.

Scheme 64

1. Remove the front door inner trim panel. Refer to TRIM PANEL REPLACEMENT - SIDE FRONT DOOR in Doors.
2. Remove the front door speaker retaining screws.
3. Disconnect the electrical connector from the front door speaker.
4. Remove the speaker from the front door.

Scheme 65

1. Connect the electrical connector to the front door speaker.
2. Install the speaker to the front door. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the front door speaker retaining screws. Tighten Tighten the front door speaker retaining screws to 2 N.m (18 lb in).
4. Install the front door inner trim panel. Refer to TRIM PANEL REPLACEMENT - SIDE FRONT DOOR in Doors.

Scheme 66

1. Remove the front door trim panel. Refer to TRIM PANEL REPLACEMENT - SIDE FRONT DOOR in Doors.
2. Remove the speaker screws (1).
3. Lift up and remove the speaker from the trim panel.

Scheme 67

1. Position the speaker to the trim panel. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the speaker screws (1). Tighten Tighten the screws to 2 N.m (18 lb in).
3. Install the front door trim panel. Refer to TRIM PANEL REPLACEMENT - SIDE FRONT DOOR in Doors.

Scheme 68

1. Remove the rear window trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
2. Remove the rear seat sound barrier. Refer to SOUND BARRIER REPLACEMENT - REAR SEAT BACK in Interior Trim.
3. Apply forward pressure in order to release the rear retainer.
4. Lift up, out and back from the rear shelf.
5. Disconnect the electrical connector from the rear speaker.
6. Remove the rear speaker from the rear shelf.

Scheme 69

1. Install the rear speaker to the rear shelf.
2. Connect the electrical connector to the rear speaker.
3. Align the forward tabs of the rear speaker into the slots.
4. Press down the rear in order to lock the tabs into the rear shelf.
5. Install the rear seat sound barrier. Refer to SOUND BARRIER REPLACEMENT - REAR SEAT BACK in Interior Trim.
6. Install the rear window trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.

Scheme 70

1. Remove the rear window trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
2. Remove the rear speaker grille nuts from the bottom of the rear speaker grille.
3. Release the rear speaker grille retainer from the rear window trim panel.
4. Pull up and out on the rear speaker grille.
5. Remove the rear speaker grille retainer.
6. Remove the rear speaker grille from the rear window trim panel.

Scheme 71

1. Align the rear speaker grille to the rear window trim panel.
2. Lock in the retainers by pressing the rear speaker grille into the rear window trim panel. NOTE: Refer to «FASTENER NOTICE»(/buick/century/vi-1997-2005/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the rear speaker grille nuts. Tighten Tighten the rear speaker grille retaining nuts to 2 N.m (18 lb in).
4. Install the rear window trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.

Radio/Audio System Description and Operation

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, and speakers.

The uplevel system differs from the base level system by providing the customer with enhanced audio system features. Some of those features include an audio amplifier and more speakers.

The following list shows the radios available for this vehicle

1. Base Radio (UM7) - AM/FM Stereo
2. Base Radio (UN6) - AM/FM Stereo, and Cassette
3. Uplevel Radio (ULO) - AM/FM Stereo, Cassette, and EQ
4. Uplevel Radio (UNO) - AM/FM Stereo, Cassette, CD, and EQ

Scheme 72

Scheme 73

Scheme 74

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

1. The power output, or wattage, of the broadcasting station
2. The location of the vehicle, or receiver, relative to the broadcast tower.
3. Obstacles between the tower and the receiver
4. Atmospheric conditions
5. Which band, AM or FM, the station is broadcasting
6. Type of antenna and the ground plane

AM Reception

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

1. Bend around obstacles
2. Follow the curvature of the earth
3. May reflect, or skip, off the ionosphere

The AM frequencies have longer range due to the ground wave. The ground wave follows the curvature of the earth and is affected 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 mi).

FM Reception

The shorter wavelengths of the higher frequency FM band

1. Reflect off obstacles
2. Are absorbed by the ground
3. Penetrate the ionosphere

Broadcasts in the FM band are limited to "line of sight" reception which is typically 40 km (25 mi). 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

1. Height of the broadcast antenna
2. Height of the receiving antenna
3. Terrain and buildings in the broadcast path

Antenna

The antenna systems available on this vehicle are fixed mast, and a passive rear window grid.

Audio Amplifier

The purpose of an audio amplifier is to increase the power of a voltage or current signal. The output signal of an amplifier may consist of the same frequencies as the input signal or it may consist of only a portion of the frequencies of the input signal, as in the case of a subwoofer or a mid-range amplifier.

Power is supplied to the amplifier from the RADIO PREM SOUND fuse in the Fuse Block-l/P.Ground is provided via G203. When the radio is turned on, the radio sends voltage signal to the amplifier via the amplifier present signal. This enables the audio amplifier to amplify the low level audio signals from the radio. The audio amplifier then sends the speaker output to the appropriate speaker.

Steering Wheel Controls

Some audio functions are available using the steering wheel controls. The steering wheel controls are actually a resistor network which consists of multiple momentary contact switches and a series of resistors. The switches and resistor network is arranged so that each switch has a different resistance value. When a switch is pressed, a voltage drop occurs in the resistor network which produces a specific voltage value unique to the switch selected. These specific Voltage values allow the radio to identify which switch has been pressed. The radio responds just as if the corresponding radio front panel button had been pressed.

The RADIO fuse in the Fuse Block-l/P provides accessory voltage to the steering wheel controls. The specific voltage signal from the switches is sent to the radio via the steering wheel controls signal circuit.

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. 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.
2. Turn the ignition to the ACC or RUN position.
3. Turn the radio off.
4. 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.
5. Press MIN and 000 will appear on the display.
6. Press MIN again to make the last 2 digits agree with the code.
7. Press HR to make the first 1 or 2 digits agree with the code.
8. 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.
9. 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 ON 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

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. IMPORTANT: If the display changes to - the theft deterrent is deactivated and no code is stored.
3. Press and hold pushbuttons 1 and 4 for approximately 6 seconds until the display changes to SEC.
4. Press the HR button.
5. Set the first 2 digits (0-19) of the code with the HR button.
6. Set the next 2 digits (0-99) of the code with the MIN button.
7. Press the AM-FM button in order to enter the code.
8. 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. IMPORTANT: If SEC is displayed the theft deterrent feature is already activated. Remove the old code before entering the new code.
3. Press and hold the pushbuttons 1 and 4 for approximately 6 seconds until the display changes to
4. Press the HR button.
5. Set the first 2 digits (0-19) of the code with the HR button.
6. Set the next 2 digits (0-99) with the MIN button.
7. Press the AM-FM button in order to enter the code.
8. Repeat steps 3-5 when REP then 00 are displayed. This will confirm the following: 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.
9. 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

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.

Tape/CD Player Error Messages

The radio displays an error when any of the following occurs

1. The radio will display error codes for the tape player and integral CD player.
2. The radio will display the following tape player error codes for tight tape, broken tape, and wrapped tape. If these conditions are detected, the radio will switch to the radio mode and eject the tape. The error code will be displayed for 5 seconds, followed by the tuner display, then the default. E10 or TIGHT TAPE-Tight tape E11 or BROKEN TAPE-Broken tape E14 or WRAPPED TAPE-Wrapped tape
3. The radio will display the following integral CD player error codes. If one of these problems is detected, the unit will switch to the radio mode and eject the CD. The display will show TOD, if the unit is off, or display the radio frequency for 5 seconds, then the default, if the unit is on. E20 or CHECK CD-Optics focus error, maybe due to moisture E21 or CHECK CD-Optics loss of tracking control, maybe due to blemishes on disc E22 or PLAYER ERR-Load/Unload motor problem E23 or PLAYER ERR-Communication problem

Scheme 75

See also:
• CHECKING AFTERMARKET ACCESSORIES
• TESTING FOR INTERMITTENT AND POOR CONNECTIONS
• DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL
• CONNECTOR REPAIRS
• CIRCUIT TESTING
• WIRING REPAIRS
• FASTENER NOTICE
• SYMPTOMS - ENTERTAINMENT
• RADIO/AUDIO SYSTEM DESCRIPTION AND OPERATION
• Radio Poor Reception
• SPEAKERS INOPERATIVE - One or More