Figure 9-43 Troubleshooting Process For Sound Failure; Table 9-11 Description Of The Signals In The Circuit Diagram In This Section - Huawei U8815 Maintenance Manual

U8815
Maintenance Manual

Figure 9-43 Troubleshooting process for sound failure

Table 9-11 describes signals in the circuit diagram in this section.

Table 9-11 Description of the signals in the circuit diagram in this section

Signal
MIC1_P
MIC1_N
AUXI_P
AUXI_N
MSM_MICBIAS
Issue 1.0 (2012-02-13)
After a call is
established, no sound is
heard by the other party.
Is the call normal after the
software is reloaded?
N
Is the call normal
after the MIC is re-soldered?
N
Is the MICBIAS voltage normal?
Y
Is the call normal
after the MIC is replaced?
N
Return the handset to the
factory for repair.
Description
Input from the primary microphone.
Input from the primary microphone.
Input from the secondary microphone.
Input from the secondary microphone.
Bias voltage of the primary microphone
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9 Principles and Failure Analysis
Y
End
Y
End
N
Check C507.
Y
End
Reference
Measurement or
Wave Form
None
None
None
None
None
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