Sim Card - Huawei U8860 Maintenance Manual

U8860
Maintenance Manual

9.4.7 SIM Card

Circuit schematic diagram
Issue 1.0 (2011-11-14)
No sound is picked up or
transmitted from the headphone.
Is J1301 normal?
Y
Is MSM_MIC_BIAS voltage normal?
Y
Is there signal is input in
MIC2N/MIC2P when speaker?
Y
Re-solder or replace
U4001.
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9 Principles and Troubleshooting
N
Replace J1301.
N
Are the components on
the MIC_BIAS1 circuit
are damaged or short-
circuited?
N
Is the circuit between
MIC2N/MIC2P and
U4001 short-circuited?
54