Zenith D35 Service Manual page 22

6. Y/C Circuit
(1)
EE Mode
Check Video at Pin28(Line Video
input) Pin30(DVD/Fr Video input)of
IC301 or Pin31(Video Input tuner).
YES
Is 5V power supplied at
Pins12, 36, 61, 67, 90, 96 of
IC301?
YES
Is Video Signal appear at
IC301 Pin52?
YES
Is Video Signal appear at
IC501 Pin43?
YES
Is Video Signal appear at
Q801 Emitter?
YES
Is Video Signal appear at
TU701 Pin6?
YES
Is 5V supplied at TU701
Pins13,14?
YES
Is VCR 'H 'Signalin TU701
Pin5?
YES
Replace TU701.
NO
Check part or jack of TU/IF.
NO
Check Power circuit.
NO
Is I 2 C BUS applied at
IC301 Pins62, 63 ?
YES
NO
Check path from IC301
Pin52 to IC501 Pin43
NO
Does 12V power flow at
C822 + Head ?
YES
NO
Check path from Q701
emitter to TU701 Pin6.
NO
Check Power Circuit.
NO
Check System.
3-10
NO
Check System.
Replace IC301.
NO
Check Power Circuit.
Replace Q701.