Sim Detect Trouble - LG U310 Service Manual

4. TROUBLE SHOOTING

4.10 SIM Detect Trouble

USB Initial sequence of 600V is :
VREG_USIM_2.85V(C429 of PM6650-2M) go to 3.0V -> USIM_CLK,USIM_RST,USIM_DATA
triggered -> USIM IF work(Schematic and place are refer to SIM technical brief)
Re-insert the SIM card
Work well?
VREG_USIM_2.85V is 3.0V?
USIM_P_CLK is run?
Change SIM card
Work well?
Change the Main board
VREG_USIM_2.85V(J300 Pin 1)
Start
Yes
No
NO
YES
Yes
No
End
Check J300,
TP_UCLK,TP_UDAT,
VREG_USIM_2.85V
End
- 100 -
USIM_P_RST
(J300 Pin 2)
USIM_P_CLK
(J300 Pin 3)
USIM_P_DATA
(J300 Pin 6)