NHL-10
CCS Technical Documentation
Baseband Troubleshooting
30
COMPANY CONFIDENTIAL
ISSUE 2 01/2004
Copyright © 2003 Nokia. All Rights Reserved.
Figure 23: External Earpiece troubleshooting
START
Set Phoenix Audio Routing from
a know n w orking MIC input,
MIC1 [HP, int] or MIC2 [Ext,
XMIC] to HF/HFCM. Ensure the
correct MIC Bias is ON.
Is the HF DC Bias
voltage seen on the HF
& HFCM lines at the
system connector?
Change UEM
Are the audio signals
from UEM to the system
connector OK?
Change UEM
Does audio w ork in a
call?
Change UPP_
WD2
END
No
Yes
No
Yes
No
Yes
No
No
No
Yes
Yes
Yes
Check audio path through R342,
Z330, Z331 and associated
passives. Check for shorts / low
impedance to GND & opens in
series components. Change
passives w here necessary.
Audio Troubleshooting
External Earpiece
Connect a know n w orking 4
terminal DCT4 headset to the
system connector.
Check system connector and PWB
contacts. Are they OK?
Clean contacts / replace system
connector, X381.
Is the HF DC Bias
voltage seen on the HF
& HFCM lines at the
system connector?
Check audio path through R342,
Z330, Z331 and associated
passives. Check for shorts / low
impedance to GND & opens in
series components. Change
passives w here necessary.
Are the audio signals
from UEM to the system
connector OK?
