U9500 Maintenance Guide
9 Troubleshooting
Issue 1.2 (2012-6-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
71
Figure 9-47
Handling process for the headset microphone failure
9.2.18 Speaker Noice
Cause
If the speaker is damped or interfered by scrap iron, speaker noise occurs.
Figure 9-48 and Figure 9-49 show the possible causes for the speaker noise problem.
Figure 9-48
Possible cause 1
There are foreign matters
in this area.
No sound heard from the headset
Check whether J1500
functions properly.
N
Replace J1500.
Y
Check whether the voltage
on AUD_HBIAS is normal.
N
Locate the fault and
resolve it.
Y
Check whether the headset
microphone is short-circuited.
N
Rectify the faults on
the signal circuit.
Y
Replace U1201.