LG -MC2670 Service Manual page 25

LG-MC2670
2.2.2 Check VCTCXO Circuit
TEST POINT Checking Flow
X100
X100 Pin4
YES
(+2.8V_TCXO)
Pin 3
VCTCXO Circuit is OK
19.2MHz OK?
See next page to check
SBI control signal
NO
YES
Pin4
Replace X100
2.8V OK?
NO
X100 Pin3 Check U400
(MSM_VCTCXO_OUT)
Circuit Diagram
Waveform
X100 Pin4 +2.85V_TCXO
X100 Pin3 VCTCXO_OUT
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