LG -H845 Service Manual page 22

Checking DRX RF signal path(B1/B2/B3/B4/B5/B8)
Checking Flow
START
Check TP1,
TP2 High Level?
(2.5V≤TP1 ≤3.1V)
(1.7V≤TP2 ≤1.9V)
YES
Check TP3
Signal exist?
YES
Check TP4
Signal exist?
YES
Check TP5
Signal exist?
YES
Check TP6
Signal exist?
YES
Check Transceiver
physical damage
or soldering condition
OK?
Check next step
LGE Internal Use Only LGE Internal Use Only
The Problem may be
Logic part
Refer to Logic
NO
trouble shoot
Check WB1/4 and
U1100 Soldering
NO
Check WB2 and
U1100 Soldering
NO
Check WB5/8 and
U1100 Soldering
NO
Check WB2/3 and
U1103 Soldering
NO
Replace
U1500/U1501
NOT GOOD
Image
TP1(2.7V)
TP4(WB2/3)
TP5(WB B5/8)
U1500
21
3. TROUBLE SHOOTING
BOTTOM
TP2(1.8V)
U1100
U1103
U1501
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reserved. Only training and service purposes reserved. Only training and service purposes
TP3(WB B1/4)
TP6(WB2/3)