How to Enable a SIM Card on Xiaomi: The Complete Guide

Modern Xiaomi smartphones, whether budget Redmi or flagship Black Shark, are equipped with complex communication modules that require the correct initial configuration. Often users are faced with a situation where after installing the operator card, the device does not see the network, and the screen remains in the status of “No connection”, this can be caused by a software failure, improper installation of the tray or specific settings of the MIUI shell.

In this article, we will discuss in detail all the steps of activation of the communication module, you will learn how to physically remove the tray so as not to damage the mechanism, and which software switches you need to activate in the settings menu for stable 4G operation. We will also touch on the issues of setting access points, which is critical for the operation of the mobile Internet.

If your phone has just been unpacked, the system may require initial network setup. SIM-The card is automatically checked, but manually checking the parameters ensures that there are no problems in the future.

Physical installation and tray inspection

The first and most obvious step is to check the physical contact. The sim card tray in Xiaomi smartphones is usually located on the bottom or side of the case. To extract, you use a special clip that comes with the kit, or a thin needle. You press the round hole next to the tray and wait for the characteristic click, after which the mechanism pushes the plastic platform.

Notice the shape of the cutout in the tray. Modern models often use a combined slot where you can install two Nano-SIM cards or one card and a microSD memory card. The correct orientation of the chip (gold contacts down or up) depends on the particular model, the circuit is always drawn on the tray itself or in the instructions. If you confuse the side, there will be no contact, and the phone will not see the subscriber.

Once you put the tray back up to the click, the device should emit an audible signal or vibration. If that doesn't happen, try gently wipe the contacts of the card with a soft eraser or dry cloth. Contact oxidation is a common reason why the smartphone doesn't detect a new chip.

In rare cases, the tray itself may be deformed or contaminated with dust. Visual inspection will help to exclude mechanical damage. If the tray enters tightly, do not use excessive force to avoid damaging the internal contacts of the motherboard.

Activation through the MIUI settings menu

After the physical installation, you need to make sure that the communication module is software activated. MIUI SIM card management is on a separate menu. → SIM-Maps and mobile networks. Both slots are displayed here, even if the second one doesn't have anything installed.

Click on the icon of the corresponding SIM card. You will see the "Use" switch. SIM-It has to be activated (blue or green slider). If the switch is turned off, the phone ignores the installed chip and the network will not appear. You can also specify the name of the network that will appear in the status bar, for example, "Worker" or "Personal».

This menu also sets priority for mobile data and voice calls, so you can choose which card is the default card and which is the default card, and which is the call-only card, which is especially convenient when using different carriers' tariffs.

• 📱 Choose the right one. SIM-map from the list of available slots.
• ✅ Make sure the switchboard is “Use”. SIM-map included.
• 🌐 Set a priority device for 4G/5G internet.
• 📞 Assign a primary card to make calls.

Sometimes the system may suggest rebooting the device after changing the settings. Don't ignore this request, as the reboot will trigger a re-registration in the operator's network with new settings.

Configure APN access points for the Internet

A common situation: calls pass, SMS arrives, but the Internet does not work, which means that the SIM card is active, but the APN (Access Point Name) hotspot is not configured. Without the right data, the phone does not know which gateway to access the global network.

To set up, go to the Settings menu → SIM-maps and mobile networks → Choose a map. → Access points (APN). In the list that opens, click on the “New Access Point” or “Reset to default settings.” The second option is often more effective, since the system will download your operator’s current settings from the database itself.

If the automatic setting doesn't work, you'll have to manually enter the settings, which you can find on your carrier's official website, and you'll usually need to fill in the Name and APN fields, and the other fields, such as username and password, are often left blank.

⚠️ Attention: When you manually enter data, be extremely attentive to the letter register. APN The internet will not work, although the signal will be full.

Once you have entered, be sure to click the menu (three dots in the corner) and select Save. Then go back to the access point list and check the box against the profile you created. Without saving, the changes will not take effect.

Network modes and choice of connection type

To work correctly in modern networks, you need to choose the desired type of network. → SIM-maps and mobile networks → The preferred network type is recommended to select the "Preferred" mode. LTE» or «5G/LTE/3G/2G (motor-car)».

Choosing a 4G Only mode can leave you without communication at all in areas with unstable coverage, as the phone will not be able to switch to 3G. Automotive mode allows the device to flexibly manage the communication module, providing a balance between speed and voice quality.

It’s also worth checking whether VoLTE (Voice over LTE) is enabled, which allows you to have high-quality conversations while using the Internet, and if this option is available from your carrier and tariff, activating it will improve the overall quality of communication.

• 🚀 Automatic mode is preferable to manual selection of standard.
• 📶 VoLTE improves the quality of voice calls in networks 4G.
• 🔄 Mode switching helps with registration problems.
• 🌍 In roaming, it is better to choose a mode «3G/2G» economy.

If you’re in a hot spot, sometimes switching to 3G Only or 2G only will help to make an important call and then returning to automatic mode.

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If the phone is constantly jumping between 3G and 4G, quickly landing the battery, try the forced LTE mode settings, which stabilizes the connection in the border areas.

Diagnostics and reset network settings

If previous steps didn't help, there may have been a build-up of software bugs in the system, and Android and MIUI have a network reset feature that doesn't delete personal data, photos or apps, but it does return everything related to Wi-Fi, Bluetooth and mobile to factory settings.

You can find this option by Settings → Connection and Sharing → Reset Wi-Fi, mobile network and Bluetooth. Confirm the action by entering the unlock password of the screen. After that, the phone will reboot, and you will have to re-enter passwords from Wi-Fi networks and reconfigure APN access points.

Another effective method is to use an engineering menu to check the status of the SIM card. Enter the code ##4636## in the call. In the menu that opens, select "Phone Information." Here you can see the status. SIM-Cards, signal level and forced ping test to run.

⚠️ Note: In the engineering menu, do not change the values in fields you do not know the value of. Incorrectly configuring the radio module can lead to the complete disappearance of the network up to a factory reset.

Also check if you have In-Flight mode. Sometimes, because of interface bugs, the airplane icon may not appear in the curtain, but the communication module will be disabled. Quickly turning on and off this mode helps to re-register on the network.

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Network reset is a secure procedure that eliminates 90% of software conflicts that interfere with the work of the network. SIM-maps on Xiaomi.

Typical problems and their solution

One of the common problems is the message «SIM-If the card is perfectly functional and works on other phones, the problem may be in the contact group of the smartphone itself, in which case it will help to clean the tray with alcohol or replace the tray.

Another problem is the blocking of IMEI. If the phone was bought from hand or brought from another country, it can be blocked by the operator. IMEI-Also make sure that the phone doesn't have a request. PIN-code that has been forgotten.

If the phone shows "Emergency Calls Only," it means it sees the network but can't sign up to it. Check balance, debt, and status of the "Honk" or "Anti-Detector" service, which sometimes conflict with registration.

• 🔍 Check the card in another device to rule out chip failure.
• 🧹 Clean the contacts of the tray with an alcohol napkin.
• 📞 Make sure there is no debt from the operator.
• 🔓 Check your phone for operator locks.

In cases where nothing helps, a complete reset to factory settings may be required.Be sure to back up the data before doing so, as all files will be deleted.