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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 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 system, the amplifier is supplied speaker signals that are shared with the rear speakers, left and right. The amplifier only supplies an amplified signal to the subwoofers. The amplifier can not set DTCs.

Diagnostic Aids

* Improper speaker mounting or loose trim may cause an audible buzz or distortion. Inspect the appropriate speaker and the surrounding interior trim for proper and secure mounting. If the speaker or surrounding interior trim is found to be loose or improperly secured, correctly secure the item.
* When equipped with an amplifier, it is possible for some individual circuit faults to affect both rear speakers. Perform diagnostic tests in the sequence listed to avoid misdiagnosis.

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

Without Amplifier

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

If audio is inoperative from all speakers, replace the radio.
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 - without Amplifier.

With Amplifier

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

If audio is inoperative from one or both subwoofers, refer to Amplifier Circuit Malfunction.
If audio is inoperative from one or more rear speakers or the audio emitted from the speakers is not clear, refer to Speaker Circuit Malfunction - with Amplifier.

Circuit/System Testing

Speaker Circuit Malfunction - without Amplifier
1. Ignition OFF, disconnect the harness connector at the appropriate speaker.
2. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.

• 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 radio.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

3. Test for 5.0-7.5 V between the signal circuit terminal B and ground.

• 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 radio.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

4. If all circuits test normal, replace the speaker.

Amplifier Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the audio amplifier.
2. Ignition OFF, test for less than 10 Ohms between the ground circuit terminals listed below and ground.

* Terminal 5
* Terminal 12

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

3. Ignition ON, test for B+ on the B+ circuit terminals listed below and ground.

* Terminal 4
* Terminal 11

• If less than the specified value, test the B+ circuit for a short to ground or an open/high resistance.

4. Radio ON, test for 5.0-7.5 V between the appropriate signal circuit terminal listed below and ground.

* Left rear speaker output (+) terminal 1
* Left rear speaker output (-) terminal 6
* Right rear speaker output (+) terminal 2
* Right rear speaker output (-) terminal 7

• 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.
• If greater than the specified range, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

5. Ignition OFF, reconnect the amplifier and disconnect the appropriate subwoofer harness connectors.
6. Radio ON, test for 5.0-7.5 V between the signal circuit terminal 1 and ground.

• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the 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 amplifier.

7. Test for 5.0-7.5 V between the signal circuit terminal 2 and ground.

• 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 amplifier.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the amplifier.

8. If all circuits test normal, replace the appropriate subwoofer.

Speaker Circuit Malfunction - With Amplifier - Front Speaker Testing
1. Ignition OFF, disconnect the harness connector at the appropriate speaker.
2. Radio ON, test for 5.0-7.5 V between the signal circuit terminal A and ground.

• 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 radio.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

3. Test for 5.0-7.5 V between the signal circuit terminal B and ground.

• 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 radio.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

4. If all circuits test normal, replace the speaker.

Speaker Circuit Malfunction - with Amplifier - Rear Speaker Testing
1. Ignition OFF, disconnect the amplifier and the appropriate speaker harness connectors.
2. Radio ON, test for 5.0-7.5 V between the signal circuit terminal A and ground.

• 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 radio.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

3. Test for 5.0-7.5 V between the signal circuit terminal B and ground.

• 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 radio.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

4. Ignition OFF, reconnect the harness connector at the audio amplifier.
5. Radio ON, test for 5.0-7.5 V between the signal circuit terminal A and ground at the appropriate speaker.

• If not within the specified range, replace the amplifier.

6. Radio ON, test for 5.0-7.5 V between the signal circuit terminal B and ground at the appropriate speaker.

• If not within the specified range, replace the amplifier.

7. If all circuits test normal, replace the speaker.

Repair Instructions

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

* 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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