LG 32LG7000 Service Manual page 17

2-2. In case of abnormal display or sound when RF mode
Check Tuner
1. VDD Check -> TU300 pin22:1.8V
pin21: 3.3V
pin4:5V
2. IIC check -> pin10,11
NG : DTV
Check DTV signal
1. TP signal -> Pin 24~34
2. IIC check -> pin 18,19
NG
Replace TU300.
NG
Replace Main B/D.
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Only for training and service purposes
Check ATV signal
NG : DTV
1. Video signal
-> TU Main Signal : R336
-> Tuner V-out:C318
NG : DTV
Check ATV sound signal
1. Sound signal
-> SIF : R317
-> SECAM-L sound:R326
No problem
Check sound processor
1. IC603 pin50 for SIF(RF sound)
2. IC603 pin47 for SECAM-L sound
No problem
Check Digital AMP
1. VDD 16V:IC600 pin49~52, 32~35
VDD 1.8V:IC600 pin2, 13, 16
2. Mute check:IC600 pin25
NG
Check App S/W
If App S/W OK then replace IC600.
- 17 -
NG
Replace TU300.
Check Front END IC100
No
1. Check C518
problem
NG
Replace TU300.
NG
Check App S/W.
If App S/W OK then replace IC603.
No problem
Check App S/W.
If App S/W OK then replace Main B/D.
Check App S/W.
NG
If App S/W OK then
replace IC100.
LGE Internal Use Only