Schematic Reference: Radio/Audio System Schematics

Always perform the Entertainment 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 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 and in Wiring Systems.

All Radios

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. Ground circuit 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 audio output from the amplifier. Replace the amplifier. Refer to Radio Speaker Amplifier Replacement .

Important: The following procedure assumes all speakers are operative for all modes of operation except digital radio.

With RPO U2K

1. Audio signal circuit shorted. Test the audio signal circuits for a short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. No audio output from the digital radio receiver. Replace the digital radio receiver. Refer to Digital Radio Receiver Replacement and Digital Radio Receiver Setup .
3. No digital radio audio output from the radio. Replace the radio. Refer to Radio Replacement .

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.

All Radios

1. Low level audio signal circuit open or shorted. Test all low level audio signal circuits for an open or short. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. No audio output from the amplifier. Replace the amplifier. Refer to Radio Speaker Amplifier Replacement .

Important: The following procedure assumes all speakers are operative for all modes of operation except digital radio.

With RPO U2K

1. Remote radio audio signal circuit open. Test the appropriate remote radio audio signal circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. No audio output from the digital radio receiver. Replace the digital radio receiver. Refer to Digital Radio Receiver Replacement and Digital Radio Receiver Setup .
3. No digital radio audio output from the radio. Replace the radio. Refer to Radio Replacement .

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.

1. Speaker output 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 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 .
3. Defective speaker. Replace the inoperative speaker. Refer to Speaker Replacement Reference .

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.

All Radios

1. Speaker output circuit high resistance. Test the appropriate speaker output circuits for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. Low level audio circuit open. Test the appropriate low level audio circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
3. Defective speaker - Replace the appropriate speaker. Refer to Speaker Replacement Reference .

Important: The following procedure assumes all speakers are operative for all modes of operation except digital radio.

With RPO U2K

1. Audio common circuit open. Test the audio common circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
2. No audio output from the digital radio receiver. Replace the digital radio receiver. Refer to Digital Radio Receiver Replacement and Digital Radio Receiver Setup .
3. No digital radio audio output from the radio. Replace the radio. Refer to Radio Replacement .