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4. TROUBLE SHOOTING
RX Trouble
LGE Internal Use Only
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Check TP 1, 2 of SW401
with RF Cable
Signal is
OK ?
Replace Mobile
SW (SW401)
Yes
No
Yes
Mobile SW & SAW filter is OK.
Check Antenna.
Check ULC2
(U102)
Control
Signal is
OK ?
No
Yes
Check TP3, 4, 5
Yes
SW401
TXON_PA
Check FL401
FL401
Signal is
OK ?
Replace FL401
Yes
No
H(2.7V)
L
BS(TP5)
L
L
TXON_PA (TP4)
H(2.7V)
H(2.7V)
VLOGIC (TP3)
PCS1900 RX
GSM850 RX
Mode
Change the PCB.
Signal is
OK ?
Replace FL401
Yes
No
Yes
TP5
TP3
TP4
TP1
TP2
TEST POINT
CHECKING FLOW