No Outside Input 1 Audio - Zenith DVR313 Series Service Manual

6. No Outside Input 1 Audio

A.
Audio
appears even in DISC
Play.
YES
Is the
IC715,IC717 -3 in the
outside input 1 mode
low?
YES
Check IC715,IC717 -7
audio signal selection.
YES
Check IC712 -13,14:
Audio signal input.
YES
IC712 -16 :HIGH?
(/RST_ADC )
YES
Check IC12 -4:
DATA output.
YES
IC6903 -1 :LOW?
(AI_SEL )
YES
Check IC6903 power and
ambient circuits.
NO Check <No audio output
appears in DISC Play>.
NO
PN6701 -8 :HIGH?
(/RST_DAC)
YES
Check IC2072 -16,17
signal flow.
Check IC715,IC717 (AUDIO SWITCH)
NO
power and switching motion.
No. 3 pin High =>No.7 pin output: A1_L/R_1
No. 3 pin Low =>No. 7 pin output: TU_L/R
NO
Check IC716 (OP-AMP )
power and ambient circuits.
NO
Check IC2084 -9, 40
=>IC2078 -14, 15 Signal flow.
NO
IC712 -2,3,7:signal input.
YES
Check IC712 power and
ambient circuits.
NO
Check IC2084 -5, 44 =>
IC2072 -6, 7 signal flow.
NO
Check
NO
3-5
Check IC2084-11,38 signal
flow.
Check IC6037 I/O circuits.