LG EC970W - Y;C CIRCUIT; No Video in EE Mode

3-13
4. Y/C CIRCUIT
(1) No Video in EE Mode,
No Video in EE Mode
Check the Video Input
Jack.
(Line In Jack)
Does the Video signal
appear at the IC301 Pin 48?
Is 5V applied to the IC301
Pins 18, 24, 42, 55, 72, 91?
Does the Video signal
appear at the IC301 Pin 65?
Does the Video signal
appear at the IC501 Pin 50?
Does the Video signal
appear at the Emitter termi-
nal of the Q701?
Check the 5.2V, 5.4VA
Line. (Power Circuit)
Is I
2
C BUS signal applied to
the IC301 Pins 68, 69?
Check C316. (AGC)
Chck the path of the signal
between the IC301 Pin 5
and IC501 Pin 50.
Replace the IC301.
Does the 12V appear at
the Emitter terminal of the
Q701.
Replace the Q701.
Check the 12V Line.
(Power Circuit)
Check the System Circuit.
(Refer to ‘SYSTEM I
2
C BUS
CHECK Trouble Shooting’)
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO