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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 at the amplifier (if equipped) 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

Programming and Relearning (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 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 - with Amplifier.



Circuit/System Testing


Speaker Circuit Malfunction - without Amplifier
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 harness connector at the appropriate speaker.
3. 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 radio.
• 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.

4. Test for 5.0-7.5 volts between the signal circuit terminal B and ground.

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

5. If all circuits test normal, test or replace the speaker.



Amplifier Circuit Malfunction
1. Ignition OFF, disconnect the X3 harness connector at the amplifier.
2. Test for less than 10 ohms of resistance between the ground circuit terminal 8 and ground.

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

3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 4 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 amplifier.

4. Disconnect the X1 harness connector at the amplifier.
5. Radio ON, test for 0.6-1.0 volts between the signal circuit terminal 8 and ground.

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

6. If all circuits test normal, replace the amplifier.



Speaker Circuit Malfunction - with Amplifier
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 and X3 harness connectors at the amplifier.
3. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left front door or tweeter - Connector X2, terminal 3
* Right front door or tweeter - Connector X2, terminal 1
* Left rear speaker - Connector X2, terminal 7
* Left rear subwoofer - Connector X3, terminal 3
* Right rear speaker - Connector X2, terminal 5
* Right rear subwoofer - Connector X3, terminal 2


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

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

* Left front door or tweeter - Connector X2, terminal 4
* Right front door or tweeter - Connector X2, terminal 2
* Left rear speaker - Connector X2, terminal 8
* Left rear subwoofer - Connector X3, terminal 7
* Right rear speaker - Connector X2, terminal 6
* Right rear subwoofer - Connector X3, terminal 6


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

5. Ignition OFF, connect the X2 and X3 harness connectors at the amplifier. Disconnect the harness connector at the appropriate 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 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 5.0-7.50 volts between the signal circuit terminal Band 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.

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



Repair Instructions

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

* Speaker Replacement Reference (Speaker Replacement Reference)
* Programming and Relearning (Programming and Relearning) for amplifier or radio replacement


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