Checking Xo Block; Trouble Shooting; Circuit Diagram - LG -H815 Service Manual

3.1 Checking XO Block

The output frequency(19.2MHz) of XO(X4100) is used as the reference one of WTR3905 and PM8994 internal VCO
Checking Flow
START
Check TP1
Is it 19.2MHz?
NO
Replace X4100 and then
check TP1
Is it 19.2MHz?
NO
The Problem may be
Logic part
Refer to
Logic trouble shoot
LGE Internal Use Only
XO Circuit is OK.
Check next step
YES
XO Circuit is OK.
Check next step
YES
U1500
TP1

Circuit Diagram

TP1
12 12

3. TROUBLE SHOOTING

Image
BOTTOM
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