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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2007 🢒 Montana SV6 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Speakers Inoperative - One or More

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 provide an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Left Front Speaker Signal Circuit

B1025*

1

B1025*

--

Right Front Speaker Signal Circuit

B1025*

1

B1025*

--

Left Rear Speaker Signal Circuit

B1025*

1

B1025*

--

Right Rear Speaker Signal Circuit

B1025*

1

B1025*

--

1. No or reduced audio.

* Noticeable audio distortion possible.

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 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. When equipped with the DVD player, the rear audio circuits from the radio pass through the DVD player an then go to the rear speakers.

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.
    • Tweeter speakers are connected to the same channel as the door speakers.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Entertainment/Communication Connector End Views

Electrical Information Reference

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

Scan Tool Reference

Scan Tool Data List

Circuit/System Verification

Radio ON, DVD Player OFF (if equipped), adjust the fade and balance controls on the radio to test all four channels individually. Each of the four channels should produce clear and even sound.

Radio ON, 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.

Circuit/System Testing

Note: If equipped with a Digital Video Disc player (DVD), the DVD must be turned off to perform proper speaker testing.

Speaker Circuit Malfunction - without DVD Player

  1. Disconnect the harness connector at the appropriate speaker.
  2. Radio ON, test for 5.0-7.5V between the signal circuit terminal A 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. Test for 5.0-7.5V between the signal circuit terminal B and ground.
    4. ⇒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.
  4. If all circuits test normal, replace the speaker.

Speaker Malfunction - with DVD Player

  1. Ignition OFF, disconnect the C1 harness connector at the DVD player.
  2. Radio ON, test for 5.0-7.5 V between the appropriate signal circuit terminal listed below and ground.
    3. • Left rear low level audio signal (+) - terminal 3
    • Left rear low level audio signal (-) - terminal 4
    • Right rear low level audio signal (+) - terminal 5
    • Right rear low level audio signal (-) - terminal 6
    ⇒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. Ignition OFF, reconnect the harness connector at the rear seat audio (RSA) module.
  4. Disconnect the harness connector at the appropriate front speaker.
  5. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.
    6. ⇒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.
  6. Test for 5.0-7.5 volts between the signal circuit terminal B and ground.
    7. ⇒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.
  7. Disconnect the harness connector at the appropriate rear speaker.
  8. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.
    9. ⇒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 DVD player.
  9. Test for 5.0-7.5 volts between the signal circuit terminal B and ground.
    10. ⇒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 DVD player.
  10. If all circuits test normal, replace the speaker.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Speaker Replacement Reference
    •  Video Disc Player Replacement
    •  Control Module References for Radio replacement, setup, and programming.