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Speaker Malfunction

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • 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 (if equipped) 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 centred 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.
    • The amplifier control circuit will measure less than 1 V when the mute function is OFF, and approximately 8 V DC when at full mute. When mute is active, the radio stops sending the varying AC voltage to the amplifier/speakers.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Radio/Audio System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-50334-50 USB Cable and Adapter Kit

Circuit/System Verification

Without Amplifier

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

⇒If audio is not heard from 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

    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.

  1. Vehicle OFF, disconnect the harness connector at the appropriate P19 speaker.
  2. Radio ON, mute OFF, test for 5.0-7.5 volts between each audio signal circuit terminal 1 and terminal 2 and ground.
    3. ⇒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. Insert the EL-50334-6 Audio Test CD from the EL-50334-50 USB Cable and Adapter Kit .
  4. Play track number three (50 Hz bass test tone) from the test CD. Test for 49-51 Hz AC between each signal circuit terminal 1 and terminal 2 and ground.
    5. ⇒If not the specified value, replace the A11 radio.
  5. If all circuits test normal, replace the speaker.

With 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.

  1. Vehicle OFF, disconnect the X1 harness connector at the T3 audio amplifier.
  2. Test for less than 10 Ω between the ground circuit terminal 8 and ground.
    3. ⇒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.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Disconnect the X2 harness connector at the T3 audio amplifier.
  5. Vehicle in Service Mode, radio ON, verify a test lamp illuminates between the remote enable signal circuit terminal 14 and ground.
    6. ⇒If the test lamp does not illuminate, test the remote enable signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the A11 radio.
  6. Radio ON, mute OFF, test for less than 1 V between the amplifier control circuit terminal 12 and ground.
    7. ⇒If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the A11 radio.
  7. Mute ON, test for less than 7.5-8.5 V between the amplifier control circuit terminal 12 and ground.
    8. ⇒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.
  8. Vehicle OFF, disconnect the X3 harness connector at the T3 audio amplifier.
  9. Radio ON, mute OFF, test for 5-7 V between the audio signal circuit terminals listed below and ground:
    10. • Left front low level audio signal (+) terminal 14
    • Left front low level audio signal (-) terminal 6
    • Right front low level audio signal (+) terminal 5
    • Right front low level audio signal (-) terminal 2
    • Left rear low level audio signal (+) terminal 12
    • Left rear low level audio signal (-) terminal 4
    • Right rear low level audio signal (+) terminal 3
    • Right rear low level audio signal (-) terminal 11
    ⇒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 A11 radio.
    ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the A11 radio.
  10. Insert the EL-50334-6 Audio Test CD from the EL-50334-50 USB Cable and Adapter Kit .
  11. Play track number three (50 Hz bass test tone) from the test CD. Test for 49-51 Hz AC between the audio signal circuit terminals listed below and ground.
    12. • Left front low level audio signal (+) terminal 14
    • Left front low level audio signal (-) terminal 6
    • Right front low level audio signal (+) terminal 5
    • Right front low level audio signal (-) terminal 2
    • Left rear low level audio signal (+) terminal 12
    • Left rear low level audio signal (-) terminal 4
    • Right rear low level audio signal (+) terminal 3
    • Right rear low level audio signal (-) terminal 11
    ⇒If not the specified value, replace the A11 radio.
  12. Vehicle OFF, reconnect all harness connectors at the T3 audio amplifier.
  13. Disconnect the harness connector at the appropriate P19 speaker.
  14. Radio ON, mute OFF, test for 5-7 V between the appropriate speaker signal terminals listed below and ground:
    15. • Door speakers or front tweeter speakers: speaker control (-) circuit terminal 1
    • Door speakers or front tweeter speakers: speaker control (+) circuit terminal 2
    • Subwoofer speaker control (-) circuit terminal A
    • Subwoofer speaker control (+) circuit terminal B
    ⇒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.
  15. Play track number three (50 Hz bass test tone) from the test CD. Test for 49-51 Hz AC between the appropriate speaker signal circuit terminals listed below and ground.
    16. • Door speakers or front tweeter speakers: speaker control (-) circuit terminal 1
    • Door speakers or front tweeter speakers: speaker control (+) circuit terminal 2
    • Subwoofer speaker control (-) circuit terminal A
    • Subwoofer speaker control (+) circuit terminal B
    ⇒If not the specified value, replace the T3 audio amplifier.
  16. If all circuits test normal, replace the appropriate P19 speaker.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Speaker Replacement Reference
    • Control Module References for amplifier or radio replacement, setup, and programming
   


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