Schematic Reference: Radio/Audio System Schematics

Connector End Views Reference: Entertainment Connector End Views

Always perform the Diagnostic System Check - Vehicle 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 U87

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

With RPO U87

1. Battery positive voltage circuit to the amplifier open--Test the battery positive voltage circuit to the amplifier for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. Low level audio signal circuit shorted--Test all low level audio signal circuits for a short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
3. Radio ON signal circuit open or shorted to ground--Test the Radio ON Signal circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
4. 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 harness connector, disconnected with the radio volume adjusted to 50 percent. If no AC voltage is present, replace the radio. Refer to Radio Replacement .
5. No audio output from the amplifier--Replace the amplifier. Refer to Radio Speaker Amplifier Replacement .