User Guide

Nokia Customer Care Baseband Description and Troubleshooting
6255/6255i6256/6256i (RM-19)
Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 57
Microphone
Audio
faults,
page 2
Audio
faults,
page 3
Is the
microphone
working?
Change the
microphone. Is it
working now?
Retest
Set mobile terminal in Local
Mode. Use Phoenix
Troubleshooting > Phone
Control > Aphone State Tab >
select Local Mode > click
Execute. Then use Audio test >
HP microphone in/HP speaker
out > Loop ON to enable the
earpiece. Talk through the
microphone.
Measure MICB1
voltage from MICP
pads on bottom
connector.
Is it ~2.1V?
Is the signal going
to the UEM at MIC1P
and MIC1N at C2113
and C2114?
Is the signal going
out of the UEM at
HSEARP, pin 12 on
the bottom
connector?
Check C2115. If
OK, change UEM.
Check audio
ASIPs Z2105,
Z2106, C2113 and
C2114, then
change the
microphone.
Check R106. If OK,
change the UEM.
Retest
NO YES
NO
YES
NO
YES
NO
YES
NO
YES