LG LG-K430DSF - Page 54

3. TROUBLE SHOOTING
54
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3.7 LTE RF PART
3.7.11 Checking RF Signal TX path(LTE B3)
Image
Checking Flow
Circuit Diagram
TP1
TP2
Main
Top
U1100
TP2
FL1107
TP1
U1002
START
Check TP1
Signal is over 21dBm?
NO
Replace U1002 and
Check Component
above RF signal path
YES
Check TP2
Signal is over 23.5dBm?
Replace U1100
NO
YES
Check Transceiver
physical damage
or soldering condition
Replace U1500
NOT GOOD
OK?
Check next step