LG 42LH3000 - Page 15

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3. AV 1/2 doesn’t display
Check JK1100, JK1101
Can you see the normal waveform?
NO
JK1100, JK1101 may have problem. Replace
this Jack.
Check the output of Main IC(IC100).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
YES
NO
After checking the Power of Main IC(IC100) you
should decide to replace Main IC or not.
This board has big problem because Main
IC(IC100) have some troubles.
After checking thoroughly all path once again,
You should decide to replace Main Board or not.
YES
4. Component doesn’t display
Check JK400
Can you see the normal waveform?
YES
NO
JK400
may have problem. Replace this Jack.
Check the output of Main IC(IC100).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
YES
NO
After checking the Power of Main IC(IC100) you
should decide to replace Main IC or not.
This board has big problem because Main
IC(IC100) have some troubles.
After checking thoroughly all path once again,
You should decide to replace Main Board or not.