U8950 Maintenance Guide V1.0
10 Principles and Failure Analysis
2012-10-22
Huawei Proprietary and Confidential
78
None
End
Y
N
End
Y
Y
End
N
N
Y
N
Re-solder the
receiver.
Y
Y
Repair the headset
connector.
Does the phone wrongly
detect the headset presence.
After a call is established, no
sound can be heard by the
other party.
Is the problem solved
after the software is
loaded?
Is the volume setting is
normal.
Check the receiver is
properly connected to the
phone.
Replace the volume key.
Does the phone function
Properly after having the
Receiver replaced?
Check whether the
surrounding circuits of
U2002 are poorly soldered.
10.3.4
Microphone
Circuit Block Diagram
Primary handset microphone
