LG C1100 Service Manual page 71

4. Trouble Shooting
Checking Flow
SETTING : After initialize Agilent 8960, Test EGSM, DCS mode
Voltage across C193
Check the signal level
at each side of MIC101. Is it a
few tens mVAC?
soldering of R110,C160,
Replace Main board.
MIC WILL WORK.
START
No
= 2.5VDC?
MIC Bias Voltage
Yes
Yes
Check the
R128, R132.
Yes
Voltage VMIC of
U102 = 2.5VDC?
Resolder R126 & R127.
No
Replace the microphone, MIC101.
No
Resolder C160, R128, R132.
Figure 4-20.
- 70 -
No
Replace U102.