LG H990ds - LTE DRx Signal Path (Bands B5, B8, B12-B28)

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reserved. Only training and service purposes
LGE Internal Use Only
3. TROUBLE SHOOTING
Checking DRX RF signal path (B5/B8/B12/B17/B20/B26/B28)
3.5.6 LTE PART – LTE B5/B8/B12/B17/B20/B26/B28 DRx
Checking Flow Image
Check TP1
Signal exist?
START
Check SW1100 Soldering
YES
NO
Check TP2
Signal exist?
YES
Check FL1200 Soldering
NO
Check TP3
Signal exist?
YES
Check U1202 Soldering
NO
Check TP4/TP5
Signal exist?
Check U1204 Soldering
NO
Check next step
Check Transceiver
physical damage or soldering
condition
OK
Replace U1401
NOT GOOD
YES
BOTTOM
TOP
TP1
(DRx Common)
SW1100
U1202
U1204
TP2
(B5/B8/B12/B17/B20
/B26/B28 DRx )
TP3
(B5/B8/B12/B17/B20
/B26/B28 DRx )
U1401
FL1200
TP4
(B5/B8/B26 DRx)
TP5
(B12/B17/B20/B28 DRx)
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