LG G7100 Service Manual page 54

4. TROUBLE SHOOTING
4.2.2 Checking VCTCXO Circuit
Test Points
X600 Pin 3
Figure 4-4
Circuit Diagram
Check Pin 3
Refer to graph 4-2
Check Pin 4
Refer to graph 4-2
X600 Pin 4
Checking Flow
13MHz OK?
No
2.75V OK?
No
Check U203,ADP3522
Waveform
13MHz
2V75_VTCXO
- 56 -
VCTCXO Circuit OK
Yes
See next page to check
ANT SW & Mobile SW
Yes
Change X600
Graph 4-2