Speaker Malfunction
Diagnostic Instructions
Circuit/System Description
Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier has 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
Scan Tool Reference
Control Module References for scan tool information
Special Tools
EL-50334-50 USB Cable and Adapter Kit
Circuit/System Verification
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. |
Circuit/System Testing
Note: To prevent misdiagnosis, the door chime must be OFF during testing. Ensure the driver door latch is closed during testing.
- Ignition OFF, disconnect the harness connector at the appropriate P19 speaker.
- Radio ON, mute OFF, test for 5.0-7.5 V between each audio signal circuit terminal 1 and 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 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. |
- Insert the EL-50334-6 Audio Test CD from the EL-50334-50 USB Cable and Adapter Kit .
- 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.
| ⇒ | If not the specified value, replace the A11 radio. |
- If all circuits test normal, replace the P19 speaker.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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