NHL-10
CCS Technical Documentation
Baseband Troubleshooting
32
COMPANY CONFIDENTIAL
ISSUE 2 01/2004
Copyright © 2003 Nokia. All Rights Reserved.
See the previous flow chart
Is the ac amplitude of
the IHF tone signal
valid?
Does audio w ork in a
call?
Change UPP_ WD2
END
No
Ye s
No
Ye s
No
No
No
Ye s
Ye s
Ye s
Check Boomer gain resistors
R337 & R336. Also check
other passives around
Boomer, especially C334,
C336 & C337.
Is the ac amplitude of
the IHF tone signal
valid?
Change Boomer
(N330)
Is the DC bias voltage
seen for both
differential IHF lines?
Check audio path from Boomer
(N330) to the IHF pads through
L359 & L360. Check for shorts /
low impedance to GND or
betw een the lines. Also check
passives around Boomer,
especially R336 to R338. Change
passives w here necessary.
Is the DC bias voltage
seen on for both
differential IHF lines?
Change Boomer
(N330)