Y/C Circuit - Zenith D35 Service Manual

3. Y/C CIRCUIT

(2)
PB Mode
YES
Luminance Signal does not
appear on Screen.
YES
Does RF Signal appear at
IC301 Pin79?
YES
Does the Luminance signal
appear at the IC301
Pins21, 26?
YES
Does the C.VIDEO signal
appear at the IC301
Pin752?
YES
Check the EE Mode.
NO
Is Power 5V suppliedat at
IC301 Pin90?
Is V.H/SW normal at IC301
Pin81?
Clean Head.
Is I 2 C BUS supplied at
IC301 Pins62,63 ?
Check System.
Is Power 5V IC301 supplied
NO
at Pins12, 36, 61, 67, 90,
96?
NO
Replace IC301.
3-11
NO
YES
NO
YES
YES
YES
NO
YES
Check 5V Power part.
Check V.H/SW level of
System.
Check 5V Power part.