Earphone Trouble - LG T5100 Service Manual

3. BASEBAND PART TROUBLE SHOOTING
Microphone Trouble
START
The voltage of
MICP = 1.8V ?
Y
A few hundreds of mV
of signals are measured ?
N
The MIC is out of order.
Change the Mic.

3.9 Earphone Trouble

Connect the handset to network equipment
and setup call
N
Check the signal
level
at MICP,MICN after
putting audio signal
Y
R328,C323,C324,L301, L302
Resolder the R331,R328,
C323,C324,L301 and L302
Figure 33. Earphone Circuit
The soldering of
N
R329 is OK ?
Y
ABB is out of order.
Resolder R329
Change the board
Y
The soldering of R331,
is OK?
N
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