3. TROUBLE SHOOTING
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Only for training and service purposes
LGE Internal Use Only
Checking Switch Block Power Source
Check ANT_SEL 0,1,2,3
High Level
1.2V < Voltage < 3V
Check the TP1(VBATT)
No
Yes
Check the Logic
In each mode
Antenna Switch Module logic(SKY77584)
ANT_SEL 0
ANT_SEL 1
ANT_SEL 2
Tx_EN
STAND-BY
LOW
LOW
LOW
LOW
GTX_LB
LOW
LOW
HIGH
HIGH
GTX_HB
LOW
HIGH
HIGH
HIGH
GRX_LB
HIGH
LOW
LOW
LOW
GRX_HB
HIGH
HIGH
LOW
LOW
WTRX_HB
HIGH
LOW
HIGH
LOW
WTRX_LB
LOW
HIGH
LOW
LOW