Zenith D35 Service Manual page 24

3. Y/C CIRCUIT
(3)
PB Mode
YES
Color Signal does not
apper On Screen.
YES
Does RF signal appear at
IC301 Pin79?
YES
Does Video Signal appear
at IC301 Pins58, 60 ?
YES
Does Color Signal appear
at IC301 Pins55, 54?
YES
Check EE MODE.
NO
Is IC301 supplied at Pin90?
Is V.H/SW normal at
IC301 Pin81?
Clean Head.
IS 5V Power Supplieda at
NO
IC301 Pins12, 36, 61, 67,
90, 96?
Does 3.58MHz appear at
IC301 Pin73?
Does 7.16MHz appear at
IC301 Pin69?
Replace IC301.
3-12
NO
YES
NO
YES
NO
NO
YES
NO
YES
NO
YES
Check 5V power part.
Check the V.H/SW level of
System.
Is I 2 C BUS applied at
IC301 Pins62, 63?
NO
Check System.
Check 5V power part.
Check IC301 X301.
Check path from IC301
Pin69 to IC301 Pin44.