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 - Vehicle in Vehicle DTC Information.

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

Without RPO U88

No audio output from the radio--Test for any AC voltage between the left front audio signal circuits at the left front speaker connector with the radio volume adjusted to 50 percent. If no AC voltage is present, check for shorts to battery positive or shorts to ground on any speaker output circuit from the radio. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. If no shorts are located, replace the radio. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

With RPO U88

1. Battery positive voltage to the amplifier open--Test the battery positive circuit to the amplifier for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. Ground to the amplifier open--Test the ground circuit to the amplifier for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
3. No low level audio output from the radio--Test for any AC voltage between the left front low level audio signal circuits at the amplifier connector with the radio volume adjusted to 50 percent. If no AC voltage is present, check for shorts to battery positive or shorts to ground on any speaker output circuit from the radio. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. If no shorts are located, replace the radio. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
4. No radio on signal to the amplifier--Test the radio on signal circuit to the amplifier for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
5. Defective amplifier--Replace the amplifier. Refer to Radio Speaker Amplifier Replacement .