Hi my name is ***** ***** I will be the expert working with you today to help understand your Samsung S4 problem.
when the screen was cracked or damages the cell phone repair guys knows what to do not just replace the touch pad and the display he must have checked the phone for its full functionality the sim card slot has nothing to do with the software upgrade.
The sim card slot must have been come out from the main motherboard due to the phone damage all it needs is to re solder the sim slot which can be done very easily by the repair guy it requires a micro soldering iron or an smd can be used too.
let me know if you have any more question.
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