GM Service Manual Online
For 1990-2009 cars only

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Auxiliary Audio Left Signal

1

1

2

--

Auxiliary Audio Left Signal

1

1

2

--

Auxiliary Audio Common Signal

--

2

2

--

1. Loss of audio channel during mobile entertainment system auxiliary play.

2. Degraded audio playback during mobile entertainment system auxiliary play.

Circuit/System Description

The auxiliary rear audio signals and auxiliary audio common circuits are outputs from the mobile entertainment player module. These circuits carry the auxiliary mobile entertainment audio signals to the disc player and video display.

Diagnostic Aids

This diagnostic assumes that the audio quality is good while playing a DVD or during play of an audio source through the mobile entertainment system. This diagnostic also assumes that the audio quality is poor or non-existent only during auxiliary mobile entertainment system play. Be sure to check for these conditions. Be sure that there is an audio selection available to play via the mobile entertainment cartridge.

Reference Information

Schematic Reference

Radio/Audio System Schematics

Connector End View Reference

Entertainment Connector End Views

Electrical Information Reference

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

Circuit/System Verification

  1. Ignition ON.
  2. Turn the radio on. Select an auxiliary mobile entertainment system as the source.
  3. Play the auxiliary selection on the mobile entertainment system.

Circuit/System Testing

  1. Ignition OFF.
  2. Disconnect the mobile entertainment player module. Test for an open, short to ground, or short to voltage on the auxiliary audio left and right signals.
  3. Test for an open, short to ground, or short to voltage on the auxiliary audio common signal
  4. If the circuits test normal, test or replace the mobile entertainment player module.
  5. If all circuits test normal, test or replace the disk player and video display .

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Mobile Entertainment Data Cartridge Access Lower Door Replacement
    •  Video Disc Player Replacement