8. Unusual display from RGB mode

Is video input

No

of the RGB jack normal?

 

(Check JK703_Pin1,

 

2,3,13,14)

 

Check the input source.

Yes

Is waveform

No

of Switching IC normal?

 

(Check IC700_Pin11,

 

12,13)

 

Check the IC700.

No

Same as Block A.

If there is normal status,

Replace main board.

9. Unusual display from HDMI 1/2/3 mode

Is video

input of the HDMI jack No normal? (Check JK900,

901,902)

Check the input source.

Yes

Check DDC

No

communication

 

lines(IC900,901,903

 

_Pin5,6

 

Check the IC900, IC901, IC903.

Yes

Check HDCP

communication lines

(IC902)

Yes

Is waveform

of Switching IC normal?

(Check IC902)

No

Same as Block A.

No

No

Check the IC902 and DHCP value

Check the IC902.

If there is normal status,

Replace main board.

Copyright © 2008 LG Electronics. Inc. All right reserved.

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LG Electronics LD84A service manual Unusual display from RGB mode, Unusual display from Hdmi 1/2/3 mode