Daewoo DV-K580NZ-T User Manual

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C. PB-Y SIGNAL N.G.
Is envelope output
from pin 7,11 of IC 401?
Is signal input at
pin 39 of IC 301?
Is 5V supplied at
pin 1, 2 of IC 401?.
NO
YES
Check PCB PATTERN 
and Q408.
NO
Is signal output from
pin 3 of IC 301?
YES
Check pin 35 Vcc 
of IC301.
NO
Check power circuit.
NO
Is SW pulse input at
pin 6 of IC 401?.
Check pin 18 of IC 601.
NO
YES
Clean head or change head.
YES
Check
Q409, 410, 411.
NO
Check power.
NO
YES
Check pin 5 EE(L)/PB(H) 
of IC 301?.
Check pin 44 of IC 601.
NO
YES
Change IC 301.
Is signal input into
pin 4 of IC 301?
Is signal output from 
pin 8 of IC 303?
NO
Check Q301, Q302, Q305.
NO
YES
Check  Q303.
YES
Is signal input into
pin 10 of IC 301?
Check IC 302 and 
Q311, Q313.
NO
YES
YES
Is signal output from
pin 34 of IC 301?
Is supplied at
pin 35 Vcc?.
NO
YES
Check power.
NO
Change IC 301.
YES
Is signal input into
pin 4 of RL 902?
Check PCB PATTERN.
NO
YES
TERMINAL OUT.
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