LG H990ds - LTE DRx Signal Path (Bands B1, B2, B3, B4, B39)

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reserved. Only training and service purposes
LGE Internal Use Only
3. TROUBLE SHOOTING
Checking DRX RF signal path (B1/B2/B3/B4/B39)
Check TP1
Signal exist?
START
Check next step
Check SW1101
Soldering
YES
NO
Check TP2/TP3/TP4
Signal exist?
YES
Check U1205
Soldering
NO
Check Transceiver
physical damage or soldering
condition
OK
Replace U1400
NOT GOOD
Check TP5
Signal exist?
Check FL1201
Soldering
NO
YES
3.5.7 LTE PART – LTE B1/B2/B3/B4/B39 DRx
Checking Flow Image
BOTTOM
SW1101
U1205
FL1201
TP1
(DRx Common)
TP2
(B1/B4 DRx)
TP3
(B2/B3 DRx)
TP5
(B39 DRx)
TP4
(B39 DRx)
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