LG 42PC55 Service Manual page 25

5-2. In case of does't display the screen into specific mode
(1) Symptom
1) The screen does not become the display from specific input mode
(RF, AV, Component, RGB, DVI).
(2) Check following
1) Check the all input mode should become normality display.
(3) In case of becomes unusual display from RF mode
Is the Tuner normal?
Yes
Is the CXA2069Q normal?
Yes
Block A
Is the FIL8548 normal?
(4) In the case of becomes unusual display from side S-video/AV mode
Is the Video input of the AV
Jack(P1400)normal?
Yes
Is the CXA2069Q normal?
Yes
Same as Block A
No
Is the Tuner Cable connected well?
No
Cable inserts well.
No
Is the Input voltage, IIC
Communication normal?
No
Is normal the Input voltage, IIC
Communication?
No
Check the input source and Cable
No
Is the Input voltage, IIC
Communication normal?
Yes
Is the Input voltage, IIC Communication
and CVBS output normal?
Replace the Tuner.
No
Replace the IC.
No
Replace the IC.
No
Replace the IC.
No