Toshiba 42HL67 - 42" LCD TV - Second Level Audio Troubleshooting; Audio Signal Input and Voltage Checks

Is
problem associated
with analog or digital
inputs?
NO YES
AnalogDigital
Suspect the
Tuner
module.
Using the power
distribution diagram,
are the voltages normal
at P812A and
P812B?
Suspect the
Low B
module.
Using
the power
distribution diagram, are
the voltages normal at
CN90A and
CN91B?
NO
YES
Suspect the digital module. This
can be confirmed by using the wiring
interconnect diagram and an oscilloscope
and checking the right and left audio
signals at CN71.
No or distorted
Audio
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