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 provide an overview of each diagnostic category.

Circuit Description

The rear seat audio (RSA) allows rear seat passengers to listen to and control any of the music sources: radio, CDs, DVDs, or other auxiliary sources. The rear seat passengers can only control the music sources the front seat passengers are not listening to. The sourced audio can be heard through wired headphones plugged into the jacks on the RSA. The RSA receives audio signals from the radio rear audio output circuits.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Entertainment/Communication Connector End Views

Description and Operation

Radio/Audio System Description and Operation

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

  1. Radio ON, RSA OFF, verify clear audio is heard from all speakers.
  2. If audio is inoperative from one or more speakers, refer to Speakers Inoperative - One or More.

Circuit/System Testing

  1. Ignition OFF, disconnect the C1 harness connector at the rear seat audio (RSA) controller.
  2. Test for less than 5 ohms between the ground circuit terminal 6 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Radio ON, test for battery voltage between the battery positive voltage circuit terminal 5 and ground.
  5. If less than the specified range, test the voltage circuit for a short to ground or an open/high resistance.
  6. If all circuits test normal, replace the rear seat audio controller.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Auxiliary Heater and Air Conditioning Control Module Replacement