User Guide

RH-51/52, RH-67/68 Company Confidential
6(a) - Baseband Troubleshooting Nokia Customer Care
Page 32 © 2004 Nokia Corporation. Issue 3 09/2004
External microphone
Figure 25: External microphone troubleshooting
External
microphone
faulty
Set phone audio routing from
MIC2 (Ext. XMIC) to known
working audio output (i.e. EAR
(HP) of HF/HFCM (Ext)). Ensure
MIC bias (MIC2) is on.
Is MIC bias
2.1V present at L616
or at the system
connetor?
Check system
connector X132.
Is it ok?
Clean contacts /
replace X132
no
Check R628 and other
passive components in
MIC bias path.
Passive
components ok? (correct
value/ no short circuit to
GND)
Change UEME
Change
defect parts
Are the
audio signals to
UEME ok?
Change UEME
Change
defect parts
Does
audio work in
a call?
Change
UPP_WD2
End
yes
yes
yes
no
no
no
yes
no
no
yes
yes
Connect headset HDB-4
to system connector
Check audio path through C633,
C634, R629, R630 and associated
passives. Also check the Hookint line
through R635. Check for shorts to
GND and open inseries components.
Passive
components ok? (correct
value/ no short circuit to
GND)