Reasons Why Xiaomi Smartphone Does Not See Sim Card

Despite the huge variety of capabilities of modern smartphones, they still continue to perform the function for which the phones were originally created. mobile communications. The functionality of this function is provided by a SIM card (and even several) inserted into a special slot.

However, there are frequent cases when both new and already used smartphones have communication problems. Xiaomi does not see the sim card. This problem has several reasons, and their most accurate detection is very important in this case, since further actions depend on them.

Software problems and their solution

These cases are good because most often the user can independently deal with this problem without resorting to the help of specialists.

• If the necessary SIM card in the curtain does not constantly work, then first it makes sense to check if the slot itself is disabled in the settings. Perhaps Xiaomi Mi4 or another device turned it off to save energy, or there was a banal failure in the operating system.

• Speaking of failure. tried to reboot? A huge number of cases where a stable “falling off” of a slot is solved by a single reboot of the phone, after which the problem no longer bothers the user.
• Is there a network? Perhaps, where you usually walk or work, the operator has no coverage, and the connection is so poor that the slot is completely disconnected.
• The modem is responsible for the performance of SIM card slots in the Android operating system. a small firmware that is completely independent. It comes complete with any firmware, however it can be changed separately without flashing the smartphone completely. You need to find a version of the modem that is different from the current one (you can see it in Settings, the item information on the phone). Installing a modem requires TWRP. The firmware of the modem is relatively universal, since Xiaomi models that are close in release have the same hardware, however, it is still advisable to look for versions specifically for your device. Place the downloaded file in the root of the memory card, reboot into TWRP and flash the modem through the Install menu. It’s possible that the slot’s functionality will not be restored with the first flashing, try several versions of the modem.

• If the slot stopped working after the next update of the operating system, then it makes sense to look for the modem firmware version from the previous version. It is very good if there is a backup of Android in TWRP, because there, most likely, the memory cards worked fine.
• A “crooked” installation of a new firmware may damage the Nvram partition. This piece of firmware contains the most important information about SIM card slots. IMEI. If it is damaged, Xiaomi Redmi 3S does not see the inserted SIM card. There are several solutions. the easiest way is to restore this section from the full TWRP backup, if any. You can try to replace Nvram using the data of another phone of the same model, and then restoring your own (be sure to save the restored section).
• Reset the smartphone to the factory settings, having previously backed up all important data.
• Flush the phone completely using a different firmware (it is advisable to find an earlier version where the SIM card was still working).
• A very rare case. a SIM card “falls off” when 3G or 4G is turned on on the phone. Contact your operator for help in setting up your phone to use the Internet.

Hardware problems and how to deal with them

Hardware nuances arise on new devices (most often this is an ordinary marriage) and on already used ones (perhaps the phone managed to fly or swim somewhere). Some nuances can be eliminated on their own, but more serious ones require knowledge of the matter.

• Does the sim card itself work? Perhaps she had long been idle, and the operator turned her off. Contact the call center to solve this problem.
• The SIM card may be very old, the contacts are damaged or oxidized. Try to clean them with a cotton swab soaked in alcohol. Also check the contacts on the smartphone itself. if necessary, do the same operation with them, using the minimum amount of alcohol to prevent it from flowing inside.

Output

If the above tips do not help solve the problem, then most likely the matter is more serious. The phone’s filling may be damaged, some wiring or a cable may be torn off (usually this is manifested by some other symptoms besides the SIM card slots). It is advisable to contact the official service center to people who know how to repair these phones.