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Part 1




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.

Diagnostic Fault Information





Circuit/System Description

Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier 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.

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 Views)
Description and Operation

Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
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

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 controlled by the radio.

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 controlled by the audio amplifier.

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 without UK6
1. Ignition OFF, disconnect the harness connector at the appropriate speaker.
2. Ignition ON, radio ON, test for 5.0-7.5 V 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.

3. Test for 5.0-7.5 V 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.

4. If all circuits test normal, replace the speaker.

Speaker Circuit Malfunction- without Amplifier with UK6
1. Ignition OFF, disconnect the X2 harness connector at the Auxiliary Radio/HVAC Control.
2. Ignition ON, radio ON, test for 5.0-7.5 V between the appropriate signal circuit terminal listed below and ground.

* Left Rear Low Level Audio Signal (+) terminal 1
* Left Rear Low Level Audio Signal (-) terminal 2
* Right Rear Low Level Audio Signal (+) terminal 3
* Right Rear Low Level Audio Signal (-) terminal 4

• 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.

3. Ignition OFF, reconnect the X2 harness connector at the Auxiliary Radio/HVAC Control. Disconnect the harness connector at the appropriate speaker.
4. Ignition ON, radio ON, test for 5.0-7.5 V 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 for front speaker circuits, replace the radio; for rear speaker circuits, replace the auxiliary radio/HVAC control.
• 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 for front speaker circuits, replace the radio; for rear speaker circuits, replace the auxiliary radio/HVAC control.

5. Test for 5.0-7.5 V 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 for front speaker circuits, replace the radio; for rear speaker circuits, replace the auxiliary radio/HVAC control.
• 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 for front speaker circuits, replace the radio; for rear speaker circuits, replace the auxiliary radio/HVAC control.

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

Amplifier Circuit Malfunction
1. Ignition OFF, disconnect the X1 harness connector at the audio amplifier.
2. Ignition OFF, test for less than 10 Ohms between the appropriate ground circuit terminal listed below and ground.

* terminal 5 (UQG)
* terminal 8 (UQA/ UQS)

• 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 appropriate B+ circuit terminal listed below and ground.

* terminal 1 (UQG)
* terminal 4 (UQA/UQS)

• 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, replace the audio amplifier.



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