User Guide

RH-48
Troubleshooting — BB CCS Technical Documentation
Page 42 © 2003 Nokia Corporation Confidential Issue 1 11/2003
Audio
faults,
page 2
Audio
faults,
page 3
Is the microphone
working?
Change the
microphone. Is it
working now?
Retest
Set phone in Local Mode. Use
Phoenix "Baseband Audio
Control" and set the following:
Enable Tx, Enable Rx, Select
MIC1, Enable HF only
(differential ended). Talk
through the microphone.
Measure MICB1
voltage from MICP
pads. Is it ~2.1V?
Is the signal going to
the UEM at MICP and
MICN at R170?
Is the signal going
out of the UEM at
XEAR, pin 11, 12 on
the bottom
connector (X101)?
Check connections
at C180 and R170. If
OK, change UEM
Check connections
at R171, R172, R173,
C171, C172, C169,
C179, C178. If OK,
change microphone
Check L103, R168,
R167, R105. If OK,
change UEM
Retest
NO YES
NO
YES
NO
YES
NO
YES
NO
YES