Schematic Reference: 
Radio/Audio System Schematics 
. 
Preliminary Information
Perform the 
Diagnostic System Check - Entertainment 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 to 
Connector Repairs 
 in Wiring Systems.
All Speakers Inoperative
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 
Circuit Testing 
 and 
Wiring Repairs 
 in Wiring Systems.
With RPO UQ7
- 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.
 
- 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.
 
Important: With RPO Y91, Bose amplifier, perform the setup procedure for the amplifier.
Refer to 
Audio Amplifier Setup 
.
- No audio output from the amplifier. Replace the amplifier. Refer to 
Radio Speaker Amplifier Replacement 
.
 
One Speaker Inoperative
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 
Circuit Testing 
 and 
Wiring Repairs 
 in Wiring Systems.
Without RPO UQ7
- Speaker output open. Test the appropriate speaker output circuits for
an open. Refer to 
Circuit Testing 
 and 
Wiring Repairs 
 in Wiring Systems.
 
Important: The radio must be programmed after replacement. Refer to 
Service Programming System (SPS) 
 in Programming.
- 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 50 percent. 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 UQ7
- Speaker output circuit from amplifier open. Test the appropriate speaker
output circuits for an open. Refer to 
Circuit Testing 
and 
Wiring Repairs 
 in Wiring Systems.
 
Important: With RPO Y91, Bose amplifier, perform the setup procedure for the amplifier.
Refer to 
Audio Amplifier Setup 
.
- 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 50 percent. 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 
.
 
Speakers - One Channel Inoperative
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 
Circuit Testing 
 and 
Wiring Repairs 
 in Wiring Systems.
With RPO UQ7
Important: With RPO Y91, Bose amplifier, perform the setup procedure for the amplifier.
Refer to 
Audio Amplifier Setup 
.
- Speaker output circuit from amplifier shorted. Test the appropriate speaker
output circuits for a short to ground or short to voltage. Refer to 
Circuit Testing 
 and 
Wiring Repairs 
in Wiring Systems.
 
- Replace the amplifier. Refer to 
Radio Speaker Amplifier Replacement 
.
 
Important: The follwing procedure assumes all speakers are operative for all modes of operation
except digital radio.
With RPO U2K
- Audio signal circuit open. Test the appropriate audio signal for an open.
Refer to 
Circuit Testing 
 and 
Wiring Repairs 
in Wiring Systems.
 
- No audio output from the digital radio receiver. Replace the digital radio
receiver. Refer to 
Digital Radio Receiver Replacement 
 and 
Digital Radio Receiver Setup 
 
- No digital output from the radio. Replace the radio. Refer to 
Radio Replacement