Buying a new smartphone is always accompanied by a pleasant expectation, but the first obstacle for the user is often the trivial task of making the device work with the mobile network. Owners of Xiaomi, Redmi and Poco equipment face the need to install and activate correctly. SIM-It's a trivial process, but modern shells. MIUI HyperOS and HyperOS have their own nuances, ignoring which can lead to a lack of signal or problems with data transmission.
In this article, we will take a detailed look at the whole way from extracting the tray to setting Internet priorities. You will learn how to correctly register a device in the operator's network, what to do if the phone does not see the module, and how to avoid blocking by IMEI. The correct sequence of actions will save your time and nerves, ensuring stable communication from the first minutes of using the gadget.
Consider that activation may vary depending on the region of purchase of the device and the software version. Global versions of firmware behave differently than Chinese ones, and the requirements of carriers in different countries also make their own adjustments.
Physical installation SIM-cardboard
The first and most important step is to physically fit the card into the slot. Modern Xiaomi smartphones are most often equipped with a combined tray or separate sockets for two nano-SIMs. An error at this stage can lead to the fact that the contacts do not close, and the phone simply will not see the module. Before starting the procedure, make sure that the device is turned off, although many modern models support hot replacement, but for initial activation it is better to be safe.
Take a special paper clip that comes with the kit, or a thin needle. On the end of the case, find a small hole next to the tray. Press it perpendicular to the case with moderate force until the tray pops out. Notice the circuit that is applied on the tray itself or in the instructions: it shows which slot to insert into which card, especially if one of them is combined with a microSD card.
Put it down. SIM-Make sure that the bevelled corner of the card matches the circuit on the tray. Don't force: if the card doesn't lie flat, you've chosen the wrong side or mistook orientation. After installation, carefully insert the tray back into the case until the characteristic click.
⚠️ Note: Never put a tray in your phone if you SIM-The card or memory card is inserted irregularly, which can cause mechanical damage to the contacts inside the smartphone, requiring expensive repairs.
Once the device is turned on, the system must automatically identify the new module. If that doesn't happen, check the purity of the contacts on the map itself and in the tray. Sometimes oxidation or dust interfere with normal connection.
☑️ Pre-insertion check
Primary registration in the operator’s network
After switching on the smartphone with installed SIM-The system starts the registration process on the network, the signal level indicators and the operator name should appear on the screen, however, in some cases, especially when using new tariff plans or when switching from another device, manual activation of the operator's services or input is required. PIN-code.
If the card is secure PIN-The system will request the code you installed before, as soon as you download it, enter the code using the on-screen keyboard. Be careful: three times entering the wrong code will block the code. SIM-map, and you will need to unlock it PUK-code that can be found on a plastic card or in the operator’s personal account.
In some cases, especially when using Chinese versions of Xiaomi smartphones with global SIM cards, it may be necessary to manually configure access points. APN. This usually happens automatically through SMS-a message from the operator, but if the Internet does not work, you will have to enter the data manually.
What to do if an activation request is received?
It is important to wait until the network search is complete. In areas of uncertain reception, this can take up to 2-3 minutes. If the network indicator flashes or shows a question mark, try moving to another place or restarting the device.
Setting up two SIM-card MIUI HyperOS
Xiaomi smartphones are famous for their dual-symbolism, allowing you to use two different numbers at the same time. However, the correct operation of both modules requires the correct configuration in the system menu. By default, the phone can use one card for all types of communication, which creates inconvenience. To manage, go to the Settings section → SIM-maps and mobile networks.
Here you will see a list of installed modules, for each of them you can specify a name (for example, "Work", "Personal"), so as not to confuse calls, and here you will adjust the priority: which card is used for mobile Internet, which is used for voice calls by default, and which is for SMS.
- 📞 Voice calls: Select Always Ask if you want to decide which card to call from before each call, or fix the main card.
- 🌐 Mobile Internet: It is recommended to assign a card with unlimited tariff or the largest packet of traffic, as a second card in standby mode can consume charge.
- 💬 SMS By default: it is convenient to install the SIM number which is tied to banks and services for obtaining confirmation codes.
Special attention should be paid to the function "Receiving calls for the second one" SIM". In some regions and some firmware, when using one card for the Internet, the second can go into mode. 2G, This makes it impossible to call in the standard 4G/LTE. Make sure that VoLTE (Voice over) is enabled LTE), If your operator supports you.
Remember that active data exchange is only through one selected card, switching between them in the settings is quick, but it takes a couple of seconds to re-register on the base station network.
Solving definition problems SIM-map
The situation when the phone says "No" SIM-cards" or "Valid SIM", It's rare, but it's panic-provoking, and before you bring a device to the service, you have to do a series of self-diagnostics, and often the problem isn't the hardware, it's the software failure or contamination.
First, do a software reset of network settings. This won't delete your personal data (photos, contacts), but will return your network settings to factory settings. To do this, go to Settings → Connection and Sharing → Reset Wi-Fi, mobile network and Bluetooth. After the restart, the phone will try to log in again.
If the reset fails, check the physical condition of the card, take it out and wipe the contacts with a soft dry cloth. SIM-If it doesn't work there, it's the operator's problem, or the module itself (the chip is burned), if the other phone is doing well, maybe your Xiaomi tray or antenna module is damaged.
| Symptoms. | Possible cause | Decision |
|---|---|---|
| "No. SIM-map" | Bad contact, software failure | Reboot, clean contacts, reset network |
| "Emergency calls only" | No cover, lockdown. | Balance check, change of seat, IMEI check |
| Continuous search of the web | Wrong APN settings | Manual setting of operator access point |
| Request. PUK-code | Multiple incorrect PIN input | Entering PUK from the plastic or operator’s website |
⚠️ Warning: If the phone was bought from hand or brought from abroad, make sure it is not locked to a specific operator (Sim-lock.
IMEI verification and activation by code
The unique IMEI device identifier plays a key role in the activation and legitimacy of a smartphone. In some countries (for example, Turkey, Belarus, Pakistan) it is required to register IMEI in the operator database or in the public register for work in local networks. In Russia and most CIS countries, this procedure is not required for ordinary users, but IMEI verification is useful for diagnosis.
To find out your Xiaomi’s IMEI, type the universal code *#06# on your phone. The screen will show the codes for each SIM slot if there are two. Compare these numbers with those on the phone box and on the sticker on the back cover (if it’s saved).
Activation in specific regions may require input of an activation code received from the operator, usually via USSD-command SMS. In the global versions MIUI When you first turn on, you may need to activate the smartphone itself through your Mi Account, which also indirectly affects the operation of communication services.
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Keep the box from your smartphone for at least a year, and it has an IMEI and serial number, which is critical when you go to a service center or police in case of a theft.
If the IMEI is displayed as "Null", "Unknown" or consists of only zeros, this is a sign of a serious software error or damage to the motherboard, in which case the SIM card is not activated until the software is restored via the computer.
Frequent errors and ways to fix them
Even after successful installation, users may experience intermittent communication interruptions or no Internet connection when calls are running, often due to network mode settings. SIM-Make sure that the card is selected Preferably 4G (LTE). If there is no coverage in your area 4G, The phone can get stuck trying to find a high-speed network, ignoring the stable network. 3G.
Another common problem is the APN settings conflict after the system update: If the Internet stopped working after the update, delete all existing access points and press the restore button for standard settings (usually a menu of three points in the corner of the screen), the operator will send the current settings.
Also worth mentioning is the influence of covers and metallic linings. Some protective glass or magnetic-latch covers can shield the antenna located at the top or bottom of the housing. Remove the case and check the signal level.
- 🔄 Reboot: a banal but working solution to 90% of network software glitches.
- ✈️ Air Mode: Turn on and off flight mode to force re-register the communication module.
- ⚙️ Setting reset: If nothing helps, a full reset to factory settings (with data) often eliminates deep software conflicts.
⚠️ Warning: When resetting to factory settings, all data on the phone will be deleted. Be sure to back up your contacts and photos to the Mi Cloud cloud or to your computer before doing this.
Adherence to these guidelines will help you avoid most connectivity problems, if none of the methods worked, and SIM-card is precisely serviceable (checked in another phone), a hardware malfunction of the antenna module or plume is likely.
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90 percent of activation problems are solved by correctly installing the card, rebooting or resetting the network settings, and hardware breakdowns are much less common.