Speaker Malfunction
Speaker Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
Circuit/System Description
Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier have a DC bias voltage that is approximately one half of battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5 V 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. The frequency (Hz) of the AC voltage signal is directly related to the frequency of the input (audio source playing) to the audio system. Both the DC bias voltage and the AC voltage signals are needed for the audio system to properly produce sound.
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 more than one speakers operation. 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 End Views By Name)
Description and Operation
Radio/Audio System Description and Operation (Radio/Audio System)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
J 39916-A CD and Cassette Diagnostic Audio Kit
Circuit/System Verification
Radio ON, Mute OFF, verify clear audio is heard from each audio T19 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 Radio and Amplifier Output Circuit Testing.
Circuit/System Testing
Amplifier Circuit Malfunction
1. Ignition OFF, disconnect the X3 harness connector at the T3 audio amplifier.
2. Ignition OFF, test for less than 10 ohm between the ground circuit terminal 8 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Verify that 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.
4. Ignition OFF, disconnect the X1 harness connector at the T3 audio amplifier.
5. Connect a test lamp between the control circuit terminal 8 and ground.
6. Ignition ON, turn the A11 radio ON and OFF. The test lamp should turn ON and OFF when changing between the commanded states.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the A11 radio.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the A11 radio.
7. If all circuits test normal, refer to Radio and Amplifier Output Circuit Testing.
Radio and Amplifier Output Circuit Testing
1. Ignition OFF, disconnect the X1 harness connector at the T3 amplifier.
2. Ignition ON, radio ON, test for 4-8 V between the control circuit terminals listed below and ground.
* Left front speaker control (+) terminal 11
* Left front speaker control (-) terminal 12
* Right front speaker control (+) terminal 9
* Right front speaker control (-) terminal 10
* Left rear speaker control (+) terminal 1
* Left rear speaker control (-) terminal 2
* Right rear speaker control (+) terminal 3
* Right rear speaker control (-) terminal 4
• If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the A11 radio.
• If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the A11 radio.
Note: In the following tests, audio signal frequencies (Hz) will be tested. To prevent misdiagnosis, the door chime must be OFF during testing. Ensure the driver door latch is closed during testing.
3. Insert the audio test CD from the J 39916-A CD and Cassette Diagnostic Audio Kit
4. Play track number three (50 Hz bass test tone) from the test CD. Test for 49-51 Hz AC between the control circuit terminals listed below and ground.
* Left front speaker control (+) terminal 11
* Left front speaker control (-) terminal 12
* Right front speaker control (+) terminal 9
* Right front speaker control (-) terminal 10
* Left rear speaker control (+) terminal 1
* Left rear speaker control (-) terminal 2
* Right rear speaker control (+) terminal 3
* Right rear speaker control (-) terminal 4
• If not the specified value, replace the A11 radio.
5. Ignition OFF, reconnect the X1 harness connector at the T3 audio amplifier.
6. Disconnect the harness connector at the appropriate T19 speaker.
7. Ignition ON, radio ON, test for 4-8 V between the appropriate control circuit terminals listed below and ground:
* Door speakers, front tweeter speakers, or center I/P speaker: speaker control (-) circuit terminal 1
* Door speakers, front tweeter speakers, or center I/P speaker: speaker control (+) circuit terminal 2
* Left subwoofer speaker control (-) circuit terminal A
* Left subwoofer speaker control (+) circuit terminal B
* Right subwoofer speaker control (-) circuit terminal C
* Right subwoofer speaker control (+) circuit terminal D
• If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the T3 audio amplifier.
• If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the T3 audio amplifier.
Note: In the following tests, audio signal frequencies (Hz) will be tested. To prevent misdiagnosis, the door chime must be OFF during testing. Ensure the driver door latch is closed during testing.
8. Play track number three (50 Hz bass test tone) from the test CD. Test for 49-51 Hz AC between the appropriate control circuit terminals listed below and ground.
* Door speakers, front tweeter speakers, or center I/P speaker: speaker control (-) circuit terminal 1
* Door speakers, front tweeter speakers, or center I/P speaker: speaker control (+) circuit terminal 2
* Left subwoofer speaker control (-) circuit terminal A
* Left subwoofer speaker control (+) circuit terminal B
* Right subwoofer speaker control (-) circuit terminal C
* Right subwoofer speaker control (+) circuit terminal D
• If not the specified value, replace the T3 audio amplifier.
9. If all circuits test normal, replace the appropriate T19 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 amplifier or radio replacement, setup, and programming