Speakers Inoperative - One or More for Pontiac Grand Prix 2004

Schematic Reference: Radio/Audio System Schematics

Connector End Views Reference: Entertainment Connector End Views

Always perform the Radio/Audio System Diagnostic System Check before proceeding with these diagnostic procedures. Refer to Diagnostic System Check - Radio/Audio System .

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 Connector Repairs in Wiring Systems.

Without RPO U87

1. Speaker output open. Test the appropriate speaker output circuits for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. No audio output from the radio. 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 no AC voltage is present, replace the radio. Refer to Radio Replacement .

With RPO U87

1. Speaker output circuit from amplifier open or shorted. Test the appropriate speaker output circuits for an open or short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. No low level audio output from the radio. Test for any AC voltage between the appropriate low level output circuits at the amplifier harness connector, disconnected with the radio volume adjusted to an audible level. If no AC voltage is present, replace the radio. Refer to Radio Replacement .
3. No audio output from the amplifier. 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 no AC voltage is present, replace the amplifier. Refer to Radio Speaker Amplifier Replacement .