Sanyo VHR-H803E Service Manual page 26

3. Y/C CIRCUIT
(2) When the Y(Luminance) signal doesn't appear on the screen in PB Mode,
Is 5.2VT, 5.4VA applied to the
IC301 Pins 24, 42, 55, 72, 91?
YES
Is the I 2 C Bus siganl applied
to the IC301 Pins 68, 69 ?
YES
Does the normal RF signal
appear at the IC301 Pin 78?
YES
Does the Y(Luminance) RF
signal appear at the IC301
Pin 76?
YES
Is the Y(Luminance) Video
waveform showed up at
theIC301 Pin 43?
YES
Replace the IC301.
NO
Check the line of the 5.2V
Line. (Power Circuit)
NO
Refer to 'SYSTEM I
CHECK Trouble Shooting'.
NO
Is the V.H.S/W signal
applied to the IC301 Pin 70?
Is V.H.S/W "H" about 3.4V
at the IC301 Pin 70?
Clean the Drum.
Check the path of the
NO
Y(Luminance) RF signal.
(Check the C312)
Check the path of the
NO
Y(Luminance) RF signal.
(Check C327)
3-13
2 C BUS
NO
YES
NO
YES
NO
YES
YES
Check the System Circuit.
(IC501 Pin 105)
Check the V.H.S/W level.
(Check R303, R304)
Replace the IC301.