Schematic Reference:
Radio/Audio System Schematics
Diagnostic System Check - Entertainment System
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. 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.
With RPO U79
- Speaker output open. Test the appropriate speaker output circuits for
an open. Refer to
Circuit Testing
and
Wiring Repairs
in Wiring Systems.
- 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 UQ3
- Speaker output circuit from amplifier open or shorted. Test the appropriate
speaker output circuits for an open or short. Refer to
Circuit Testing
and
Wiring Repairs
in Wiring Systems.
- 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.
- No low level audio output from the radio. Test for any AC voltage between
the appropriate 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
.
- 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
.