4. TROUBLE SHOOTING
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Check TP1 of SW400
TP1 Signal is OK?
Replace Mobile SW (SW400)
Check TP2 of U400
Control Signal
Is (TP3, 4, 5)
OK ?
Yes
Yes
Yes
No
No
Mobile SW & TX Module is OK.
TP6(High Band),
TP7(Low Band) Signal is OK ?
Check MT6255(U101)
No
Replace TX module (U400)
TX Module Mode
Tx ENABLE
GpCtrl1
GpCtrl0
Off
0
0
0
RX 0
0
1
0
RX 1
0
1
1
GSM850/900 TX Mode
1
1
0
DCS1800/PCS1900 TX Mode
1
1
1