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Speaker Malfunction



Speaker Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



Diagnostic Fault Information






Circuit/System Description

Each of the audio output channel circuits (+) and (-), at the radio, Cd changer, and audio amplifier have a DC bias voltage that is one half of the battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. This voltage will vary depending on what type of audio is being listened to, talk or music, and type of music, as well as the volume setting of the system. Low volume and talk settings will measure around 1V AC and less, where constant music may measure 3V AC and slightly higher. In an amplified audio system, these similar AC voltage measurements may be slightly higher on the output of the amplifier, and the typical AC voltage readings at the output of the radio are less than 1V AC .


Reference Information
Schematic Reference

Radio/Navigation System Schematics (Radio/Navigation System Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Verification

1. Radio ON, verify clear audio is heard from each audio speaker.

• If audio is inoperative from all speakers, refer to Amplifier Circuit Malfunction.
• If audio is inoperative from one or more, but not all speakers or the audio emitted from the speakers is not clear, refer to Speaker Circuit Malfunction.

2. Radio ON, verify the CD changer operates properly.

• If the CD changer does not operate properly, refer to Compact Disc Inoperative (Compact Disc Inoperative) .




Circuit/System Testing


Amplifier Circuit Malfunction
1. Ignition OFF, disconnect the X1 harness connector at the audio amplifier.
2. Test for less than 10 ohms between the ground circuit terminal A and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal H and ground.

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the circuit fuse is open, replace the audio amplifier.

4. Ignition OFF, disconnect the X2 harness connector at the audio amplifier.
5. Radio ON, test for 5.0-7.5 volts between the audio signal circuit terminal listed below and ground.

* Left low level audio signal (+) terminal B10
* Left low level audio signal (-) terminal B9
* Right low level audio signal (+) terminal B11
* Right low level audio signal (-) terminal B8


• If greater than the specified range, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the CD changer.
• If less than the specified range, test the appropriate signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the CD changer.

6. Disconnect the X1 (digital radio) or X2 (standard radio) harness connector at the CD changer.
7. Radio ON, test for 5.0-7.5 volts between the audio signal circuit terminal listed below and ground.

* Left audio signal (-) terminal 14
* Right audio signal (+) terminal 5
* Left audio signal (-) terminal 4-standard radio
* Right audio signal (-) terminal 15-standard radio
* Audio common signal terminal 13-digital radio


• If greater than the specified range, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
• If less than the specified range, test the appropriate signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.

8. If all circuits test normal, replace the audio amplifier.



Speaker Circuit Malfunction
1. Ignition OFF, inspect the appropriate speaker and the surrounding interior trim for proper and secure mounting. Improper speaker mounting or loose trim may cause an audible buzz or distortion.

• If the speaker or surrounding interior trim is found to be loose or improperly secured, correctly secure the item.

2. Disconnect the X2 harness connector at the audio amplifier.
3. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left low level audio signal (+) terminal B10
* Left low level audio signal (-) terminal B9
* Right low level audio signal (+) terminal B11
* Right low level audio signal (-) terminal B8


• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the CD changer.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the CD changer.

4. Ignition OFF, connect the X2 harness connector at the audio amplifier.
5. Disconnect the harness connector at the inoperative speaker.
6. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.

• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the audio amplifier.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the audio amplifier.

7. Test for 5.0-7.5 volts between the signal circuit terminal B or terminal C and ground.

• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the audio amplifier.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the audio amplifier.

8. If all circuits test normal, replace the inoperative speaker.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Remote CD Changer Replacement (Removal and Replacement)
* Speaker Replacement Reference (Speaker Replacement Reference)
* Control Module References (Programming and Relearning) for Audio Amplifier and Radio replacement, setup, and programming


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