Download Zenith DP5 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?
NO
Is Power 5V suppliedat at
IC301 Pin90?
NO
Check 5V Power part.
YES
Is V.H/SW normal at IC301
Pin81?
NO
Check V.H/SW level of
System.
YES
YES
Clean Head.
YES
Is I2C BUS supplied at
IC301 Pins62,63 ?
YES
Check System.
Does the Luminance signal NO
appear at the IC301
Pins21, 26?
Is Power 5V IC301 supplied NO
at Pins12, 36, 61, 67, 90,
96?
YES
YES
Does the C.VIDEO signal
appear at the IC301
Pin752?
NO
Replace IC301.
YES
Check the EE Mode.
3-11
Check 5V Power part.