LG KP270 Service Manual page 105

4. TROUBLE SHOOTING
417.2 Checking Front-End Module Block
TP7 TP7
TP P 8 TP8
TP6 TP6
TP5 TP5
LGE Internal Use Only
Check TP9 of SW501
with RF Cable
TP9 Signal
Same as TP10 ?
YES
Check TP11
(FB503) = 2.85V ?
YES
Check the Logic
In each mode ,
TP1~4 High level
2.85 Vcc 1.4V ?
YES
FL501 Pin 12~19
Signal OK?
(In each mode)
Front end module is Ok.
See the next page
- 106 -
NO
Replace SW501
NO
Check
2V85_VRF net
Check U505
NO
Or
Replace FL501
NO
Replace FL501
TP4 TP4
TP3 TP3
TP2 TP2
TP1 TP1
TP10 TP10
TP9 TP9
TP11 TP11
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