Troubleshooting - Sony KV-13FS100 Product & Training Manual

Troubleshooting

No Audio from IC404 (inputs OK): check the following:
•
PS401 for open condition
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Voltage at IC404/pin 5 (~3V). If voltage is low or missing check, Q411 and Q435 for shorted condition.
•
Voltage at IC404/pin 9. If this voltage goes below 0.5V, the unit will mute. This is true even when
IC400 audio processor is installed.
•
If all voltages and inputs check OK, replace IC404
No audio output from IC400:
•
Check audio input from audio jacks
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Check power supply IC400/pin 21 (9V)
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Check IC400/pin 18 (Data) and IC400/pin 19 (Clock)
Check for presence of digital signal
No audio output from IC401 (IC402):
•
Check audio input from audio jacks
•
Check power supply IC401/pin 14 (9V)
•
Check power supply IC402/pin 6 (9V)
•
Check two bit binary switch pattern IC401 (IC402)/pins 2 and 4. (Ref. Table 7-1)
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7. Audio