W900/850 Transception Circuit - Huawei U8185 Maintenance Manual

U8185
Maintenance Manual

9.3.3 W900/850 Transception Circuit

W900/850 RF transception circuit filter, PA, duplexer, and antenna switch
Issue 1.0 (2012-03-23)
No W2100/1900
reception
Upgrade the
software. Problem
solved?
N N
Is the antenna in
good contact?
Y Y
Is U3304 soldered
properly?
Y Y
Are C3601, L3601,
and C3602 (R3602)
soldered properly?
Y Y
Are R3701 (R3702),
C3710, and L3704
soldered properly?
Y Y
Is U3702 soldered
properly?
Y Y
Are L3705, C3701,
and C3702 soldered
properly?
Y Y
Send the phone to an
advanced service site
for repair
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Copyright © Huawei Technologies Co., Ltd.
Y Y
End
Re-install the
N N
antenna
Re-solder or replace it
N N
Re-solder or replace
N N
them
Re-solder or replace
N N
them
Re-solder or replace it
N N
Re-solder or replace
N N
them
9 Principles and Failure Analysis
43