LG -H845 Service Manual page 24

Checking Tx signal path(B1/B2/B3/B4/B5/B8)
Checking Flow
START
Check TP1
+VPWR OK?
YES
Check TP2
3.2V≤TP2≤4.2V?
YES
Check TP3/4/5/6/7
If WCDMA B1/2/3/4 Over 22.5dBm?
WCDMA B5 Over 23dBm
WCDMA B8 Over 24dBm
NO
Check TP8/9
If WCDMA B1/2/3/4/5/8
Over 3dBm?
NO
NOT GOOD
Check Transceiver
physical damage
or soldering condition
OK?
Check next step
LGE Internal Use Only LGE Internal Use Only
The Problem may be Other part
Check Logic part
NO
Check DC-DC Power Block
NO Refer to 3.3
Check component
YES above RF signal path
Check U1300 soldering
YES
Replace U1500/U1501
Image
BOTTOM
TP8(WCDMA B1/B2/B3/B4)
U1300
TP2(+VP0)
TP1(+VBAT)
23
3. TROUBLE SHOOTING
TP9(WCDMA B5/B8)
TP4 (WB3/4 Tx)
TP3 (WB1 Tx)
TP5 (WB2 Tx)
TP6 (WB5 Tx)
TP7 (WB8 Tx)
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reserved. Only training and service purposes reserved. Only training and service purposes