Nokia NPM-6 Series Troubleshooting Instructions page 37

CCS Technical Documentation
Audio faults
3
IHF speaker working ?
Yes
END
Set buzzer ON, vol "9" and freq. to 1kHz.
Check C173,
C174, C175, L151, L152,
C170, C171, C172 and
IHF PA output lines.
Retest.
Issue 1 01/03
Try to change new
No
C-cover assembly
Yes
Restore old C-cover
Set phone to local mode with Phoenix.
Measure DC-
level between IHF
No
pads J156/J157 to
GND.
Is it ~1.8V ?
ãNokia Corporation.
Troubleshooting Instructions
IHF speaker or
contact springs
Yes
fault.
Restest
Measure AC-
level between IHF
Yes
pads (J156,J157).
Is it ~1.0Vrms ?
No
Check signal in C161.
Is it OK ?
Yes
Check IHF PA
controls on J152,
J523,J154.
Is it OK ?
Change UPP
Speaker
contact springs
Yes
faults.
Retest
Check C161,
C160,R163,
No C169.
If OK then
change UEM
Change IHF PA
(N150)
Yes
Page 37