GM Service Manual Online
For 1990-2009 cars only

Important: 

  1. Perform the Diagnostic System Check - Radio/Audio System before using the Symptom Tables in order to verify that all of the following are true:
  2.    • There are no DTCs set.
       • The control module(s) can communicate via the serial data link.
  3. Review the system operation in order to familiarize yourself with the system functions. Refer to:
  4.    •  Steering Wheel Controls System Operation
       •  Radio/Audio System Description
       •  Radio/Audio System Operation
       •  Radio/Audio System Circuit Description
       •  Steering Wheel Controls System Circuit Description
       •  Vehicle Personalization/Customization

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the Radio/Audio System. Refer to Checking Aftermarket Accessories in Wiring Systems.
    • Inspect for easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    •  Radio Poor Reception
    •  Audio Distortion - One or More Speakers
    •  Audio Too Loud at Low Settings
    •  Compact Disc General Diagnosis
    •  Remote Playback Device Inoperative
    •  Remote Playback Device - Audio Noise
    •  Remote Playback Device Left or Right Channel Inoperative
    •  Tape Player Weak, Slow, or Garbled Output
    •  Steering Wheel Controls Inoperative
    •  Speakers Inoperative - One or More
    •  Speakers Inoperative - All
    •  Tape Player Diagnostic Check