LG 32LD340H Service Manual page 48

RGB-PC Video Trouble shooting guide
Check input signal format.
Is it supported?
YES
Check AC cable for damage
For damage or open conductor
YES
Check EDID & EEPROM
IC1105 I2C signal
R1141, R1143(SDA,SCL)
YES
Check P1103
Can you see the normal waveform?
YES
Check the input of Mstar(IC101).
Measure waveform at R4024, R4025
because it's more easy to check.
Can you see the normal waveform?
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NO
Replace the defective IC or re-download EDID data
NO
P1103 may have problem. Replace this Jack.
YES
This board has big problem because Main chip (Mstar) have some troubles.
After checking thoroughly all path once again, You should decide to replace Mstar or not.
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