GM Service Manual Online
For 1990-2009 cars only

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.

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

Special Tools Required

J 39916-A CD Diagnostic Audio Kit

Circuit/System Testing

Without Amplifier

Ignition ON and radio ON. Adjust the fade and balance controls to mid range and insert the CD from the J 39916-A to identify the suspect speaker.

Replace suspect speaker if distortion is found.

With Amplifier

  1. Ignition ON and radio ON. Adjust the fade and balance controls to mid range and insert the CD from the J 39916-A to identify the suspect speaker.
  2. Ignition OFF, Disconnect the suspect amplifier harness connector.
  3. Test for less than 1 volt at the amplifier connector suspect speaker high and speaker low terminals
  4. If greater than specified value, repair short to voltage.
  5. Test for greater than 1 ohm between the amplifier connector suspect speaker high and speaker low terminals and ground.
  6. If less than specified value, repair short to ground.
  7. If all circuits test normal, replace the suspect speaker.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Speaker Replacement Reference