LG F1200 Service Manual page 69

4. TROUBLE SHOOTING
(3) Checking RF Chipset Control Signal
Checking Points
Checking Flow
Check SENB, SCLK, SDI
Refer to Waveform
Check if there is any
Major Difference
Control Signal Circuit Diagram
R558
390
R557
390
R556
390
C559 C560 C561
10p 10p 27p
U102
Similar ?
Yes
Control Signals is OK
See next page to check
BQP RFID
2
BQN U102 RFIP
3
BIP SI4206 RFIP
4
BIN GN
5
XTAL1 GN
6
XTAL2 GN
7
XAFC GN
GN
- 68 -
SDI
SCLK
SENB
Redownload
phone S/W
No
Waveform