Y/C Circuit - Zenith XBV613 - DVD/VCR Combination Service Manual

5. Y/C CIRCUIT

(1) No Video in EE Mode,
No Video in EE Mode
Does the Video signal
appear at IC301 Pins28,
30, 32?
YES
Is REG 5.0V applied to
IC301Pins23, 44, 45, 52,
68, 77?
YES
Does the Video signal
appear at IC301 Pin26?
YES
Does the Video signal
appear at IC501 Pin52?
YES
Does the Video signal
appear at the Q924
Emitter?
Does the Video signal
NO
appear at IC302 Pins1,
3?
YES
Is there SW5V at
IC302 Pin6?
YES
Replace IC302.
NO
Check the SW 5V Line.
(Power Circuit)
NO
Is I 2 C BUS signal applied to
IC301 Pins53, 54, 55?
YES
Check the path of the sig-
NO
nal between the IC301 Pin
26 and IC501 Pins50, 52.
NO
Is there 12V on the
terminal of R905?
YES
Replace Q924.
3-10
Check DVD Video Input
NO
(IC601, Pin150), Tuner
Video Input (TU701 Pin16),
Line Video Input (JK901),
respectively.
Check the System Circuit.
NO
(Refer to 'SYSTEM I
CHECK Trouble Shooting')
Replace IC301.
NO
Check the SW 12V Line.
(Power Circuit)
2 C BUS