Sim Detect Troubleshooting - LG U830 KU830 Service Manual

4.11 SIM Detect Troubleshooting

USIM Initial sequence of U830 is :
USIM_CLK,USIM_RST,USIM_DATA triggered → VREG_UIM_2.85V go to 3.0V → USIM IF work
Re-insert the SIM card
Work well?
VREG_UIM_2.85V is 3.0V?
USIM_P_CLK is run?
Change SIM card
Work well?
Change the Main board
Start
Yes
No
NO
Check the Sub PCB and
Main Connector
YES
Yes
No
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4. TROUBLE SHOOTING
End
YES
Check J1
End
VREG_USIM_2.85V(J700 Pin 1)
USIM_P_RST(J1 Pin 2)
USIM_P_CLK(J1 Pin 3)
J1
USIM_P_DATA
(J700 Pin 7)