Sharp XG-PH70X Service Manual page 45

Check Video signal input.
Go to "Checking the Video circuit".
Are there signal at C411 output?
YES
Are there signal at emitter of Q412 output?
YES
Are there signal at pin (5) of IC406?
YES
CN3001 is not stable or breakdown.
Check Audio signal input of Video.
Go to "Checking the Audio circuit".
Are there signal at C420 output?
Are there signal at C423 output?
YES
Are there signal at pin (7) of IC402 and IC404?
YES
Are there signal at C445 output?
Are there signal at C447 output?
YES
CN3001 is not stable or breakdown.
Check Audio signal input of PC1.
Go to "Checking the Audio circuit".
Are there signal at C412 output?
Are there signal at C413 output?
YES
Are there signal at pin (7) of IC402 and IC404?
YES
Are there signal at C445 output?
Are there signal at C447 output?
YES
CN3001 is not stable or breakdown.
XG-PH70X/XG-PH70X-N (1st. Edition)
NO Check C411 and its peripheral circuits.
NO Check Q412 and its peripheral circuits.
NO Check IC406 and its peripheral circuits.
NO Check C420, C423 and their peripheral circuits.
NO Check IC402, IC404 and their peripheral circuits.
NO Check C445, C447 and their peripheral circuits.
NO Check C412, C413 and their peripheral circuits.
NO Check IC402, IC404 and their peripheral circuits.
NO Check C445, C447 and their peripheral circuits.
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