GM Service Manual Online
For 1990-2009 cars only

Schematic Reference: Radio/Audio System Schematics

Preliminary Information

Review the Radio/ Audio Description and Operation and perform necessary inspections. Refer to Radio/Audio System Description and Operation .

Important: The following information lists the most probable cause of the concern to the least probable cause. If the list leads to the replacement of a component, always inspect for a poor connection before proceeding with replacement. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems.

One Speaker Inoperative

  1. Speaker output open. Test the appropriate speaker output circuits for an open. Refer to Circuit Testing , and to Wiring Repairs in Wiring Systems.
  2. Audio output from the radio is not evident. Test for any AC voltage between the appropriate speaker output circuits at the speaker harness connector, disconnected with the radio volume adjusted to an audible level. If AC voltage is present, replace the speaker. Refer to Speaker Replacement Reference . If AC voltage is not present, replace the radio. Refer to Radio Replacement .

All Speakers Inoperative

  1. Speaker output shorted -- Test all speaker outputs for a short. Refer to Circuit Testing , and to Wiring Repairs in Wiring Systems.
  2. Faulty radio -- Replace the radio. Refer to Radio Replacement .