Read LG 42LV3700-UD (CHASSIS:LA12B) Service Manual online
Check input signal format.
Is it supported?
Check RGB Cable conductors
for damage or open conductor
Check EDID & EEPROM
IC3802 I2C Signal R3811, R3812(SDA,SCL)
Check P3801
H/V_Sync/R/G/B Signal Line
L3806/7/8
ok
ok
ok
No
No
Re-download EDID data or Replace the defective IC
ok
Replace Jack
Check DSUB_DET
Replace R3815
No
ok
No
Check BCM LVDS Output
Replace BCM( IC101).
6. Trouble shooting - No video (RGB-PC)
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