Sharp XG-PH70X Service Manual page 44

XG-PH70X/XG-PH70X-N (1st. Edition)
Audio output in trouble
Page 4-4 Check the audio output circuit
and its parts.
Check S-Video signal input.
Go to "Checking the S-Video signal circuit".
Are there signal "C" at C418 output?
Are there signal "Y" at C419 output?
Are there signal "C" at emitter of Q414 output?
Are there signal "Y" at emitter of Q415 output?
Are there signal at pin(7) of IC406?
CN3001 is not stable or breakdown.
Checking the PWB Performance
RGB + HV input in trouble
Feed the pattern signal from source.
Is specified cable Connected between
Source and projector?
Is supply voltage as specified?
Does image appear?
Check the PC I/F unit
YES
YES
YES
NO
YES
NO
YES
NO
YES
NO Check C418, C419 and their peripheral circuits.
NO Check Q414, Q415 and their peripheral circuits.
NO Check IC406 and its peripheral circuits.
4 – 2
RS232 channel input in trouble
Check the RS232 channel input signal from
source.
Use specified cable.
Power circuit in trouble.
Check the connectors, starting from the
Source input circuit.