For 1990-2009 cars

### Speaker Inoperative -- One or More

Schematic Reference: Radio/Audio System Schematics

#### Without RPO U67

1. No audio output from the radio.

Test for any AC voltage between the audio signal circuits at the affected speaker connector with the radio volume adjusted to 50 percent. If no AC voltage is present, check for shorts to battery positive voltage or shorts to ground on all speaker output circuits from the radio. If no shorts are located, replace the radio. Refer to Radio Replacement .

2. Speaker output open.

Test the appropriate speaker outputs 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 .

#### With RPO U67

1. Speaker output from amplifier open.

Test the appropriate speaker outputs for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

2. Defective speaker.

Replace the appropriate speaker. Refer to Speaker Replacement Reference .

3. No audio output from the amplifier.

Test for any AC voltage between the audio signal circuits at the affected speaker connector with the radio volume adjusted to 50 percent. If no AC voltage is present, check for shorts to battery positive voltage or shorts to ground on the affected speaker outputs. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. If no shorts are located, replace the amplifier. Refer to Radio Speaker Amplifier Replacement .