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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 has 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 centred 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.

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 has less than 1V when the mute function is OFF, and will have 4-6V DC when at full mute.

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

Circuit/System Testing

Note: If equipped with surround sound, the surround sound should be turned OFF for proper voltage values when performing speaker testing.

  1. Ignition OFF, disconnect the wiring harness plug at the audio speakers.
  2. Radio ON, test for a varying mV AC voltage reading between the following signal circuit terminals listed below and ground. Test for a varying mV AC voltage reading between the following signal circuit terminals listed below and ground.
    3. • Left front audio signal (+) terminal 2
    • Left front audio signal (-) terminal 1
    • Right front audio signal (+) terminal 2
    • Right front audio signal (-) terminal 1
    • Left rear audio signal (+) terminal 2
    • Left rear audio signal (-) terminal 1
    • Right rear audio signal (+) terminal 2
    • Right rear audio signal (-) terminal 1
    ⇒If the varying mV A/C voltage reading is not present, test the signal circuit for a short circuit to voltage, short circuit to ground, or an open/high resistance. If the circuit tests normal, replace the radio.
  3. If all circuits test normal, replace inoperative speaker.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Radio Replacement

   


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