If you own a Xiaomi, Redmi or POCO smartphone, you've probably encountered a mysterious SIM activation service in your device settings, a feature that appears on the mobile menu, but is rarely explained in plain language, and it affects connectivity, Internet speed, and even the ability to make calls in some regions.
In this article, we will discuss in detail what the term “SIM activation service” hides, how it interacts with telecom operators, why it can interfere with the operation of the phone – and what to do if it constantly requests activation or issues errors.
What is the “SIM activation service” in Xiaomi?
Function “Activation service” SIM» (english-language — SIM Activation Service is a proprietary solution Xiaomi designed to optimize the work with the company. SIM-It does three key things:
- 🔄 Automatic setup APN — selection of Internet access parameters for your operator (for example, Internet.beeline.ru or mms.tele2.ru).
- 📡 Network Profile Management – Selecting a Preferred Communication Standard (4G/LTE, 5G, 3G) depending on the coverage.
- 🔒 Authentication in the operator’s network – exchange of data with Xiaomi servers to confirm legality SIM-maps (relevant to some regions).
It is essentially an intermediary between your SIM-map and operating system MIUI. Ideally, the service should make it easier to connect to the network, but in practice it often becomes a source of problems – especially if you are a user:
- 🌍 Use the phone outside of China (where the feature was originally developed).
- 📱 Install custom firmware or global version MIUI Chinese-made.
- 🔄 Change often. SIM-Cards or use virtual operators (MVNO).
How does SIM activation affect your phone?
In most cases, the function works invisibly, but its failures are pronounced, and here are typical symptoms indicating service problems:
| Symptoms. | Possible cause | Decision |
|---|---|---|
| Continuous notification Activate SIM-map | The service cannot confirm the legitimacy of the card from the operator | Disable the service in settings or reset APN |
| No mobile internet with working calls | Incorrect APN settings due to service failure | Manually set up APN or reboot your phone |
| Phone does not catch the network after the MIUI update | Conflict of the service version with firmware | Update MIUI to the latest version or roll back changes |
| Constant switching between 4G and 3G | The service mistakenly selects a network profile | Set the communication standard manually |
Xiaomi users in Russia after 2022 are particularly affected by the problem, because the activation service is initially aimed at Chinese operators (China Mobile, China Unicom), and for foreign operators. SIM-It's not working properly, like it can block access to the map. LTE, If you don’t get a response from Xiaomi servers in China.
⚠️ Note: If you use Xiaomi from the Russian SIM-The card and see the notification Required activation SIM, Don't rush to follow instructions, it can be a false positive, and 90 percent of the time, the problem is solved by shutting down the service.
Where is the SIM activation service in the settings?
The path to function depends on the MIUI version and the phone model, and here are the current options for firmware 2023-2026:
- 📱 MIUI 14 and newer: Settings → SIM-maps and mobile networks → [Choose. SIM] → Activation service SIM.
On some models (e.g. Xiaomi) 12T or POCO F5) The option is only available when inserted SIM-If you don't see it on the menu, try it:
- Reboot the phone.
- Insert SIM-The card is another slot (if there are two of them).
- Update MIUI to the latest version.
What to do if the item is not in the settings?
How to disable the activation service SIM?
If a feature interferes with the phone, it can be deactivated. Here's a step-by-step instruction:
1. Go to Settings. → SIM-maps and mobile networks
2. Choose a problem SIM-map
3. Find the SIM activation service and tap it
4. Transfer the slider to the off position.
5.Reboot the phone to apply the changes
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After the shutdown:
- ⚠️ You may have to manually adjust. APN (parameters can be requested from the operator).
⚠️ Attention: On phones with MIUI For the Chinese market (for example, Xiaomi 13 Pro) CN) Disabling the service can lead to total loss of the network, in which case only the firmware of the global version will help.
Frequent SIM activation service errors and their solutions
Let’s look at typical failures and ways to fix them.
Notice “Activate” SIM-map doesn't disappear
The reason: The service cannot confirm the legitimacy of the card from the operator (often with virtual operators such as Yota or Tinkoff Mobile).
Decision:
- Turn off the SIM activation service (see instructions above).
- Check if the firewall or VPN is blocking access to Xiaomi servers.
- Set the manual network selection mode in the settings SIM-map.
2. no mobile Internet after activation of the service
Reason: The service reset APN settings or chose an incorrect profile.
Decision:
- Go to Settings. → SIM-map → [Yours. SIM] → Access points (APN).
- Click Reset to default values or create a new APN manually (options can be found on the operator’s website).
- Save the settings and restart the phone.
3.The phone doesn't catch the 4G/5G network
Reason: The SIM activation service forcefully switches the phone to 3G or 2G.
Decision:
- Set the network standard manually: Settings → SIM-map → Preferred type of network → 4G (recommended).
- If the option is not available, install the Network Signal Guru app from Google Play to force the standard to be selected.
💡
If you have lost your VoLTE (4G calls) after you turn it off, try to turn it on through the engineering menu. To do this, type in the Phone application code ##4636##, select Phone Information and activate the VoLTE provisioned option.
SIM activation service and custom firmware
If you have an alternative firmware installed (like LineageOS, ArrowOS, or Pixel Experience), the SIM activation service will be disabled by default — it simply isn’t in these builds.
- ✅ Pros: No unnecessary background processes consuming the battery.
- ⚠️ Cons: You will have to manually adjust APN For each operator, the proprietary functions may not work. MIUI (Like, double. 4G Some models (e.g. Xiaomi) or VoLTE video calls. 12S Ultra) require patches for modems to work properly with Russian operators.
If after firmware the phone stopped catching the network, check:
- Compatibility with your modem model (Xiaomi often has different modifications for regions).
- File availability modemst1.st and modemst2.st file /vendor/firmware_mnt (Their absence is a common cause of problems).
- Correctness of installed radio modules (you can download them separately for your model on the XDA Developers forum).
💡
Custom firmware often requires a modem and radio flash from the stock global version of MIUI to run smoothly, solving 80 percent of connection problems.
Alternatives to SIM activation service
If you have disabled the feature but want to save automatic network setup, consider these options:
| Decision | Pluses | Cons |
|---|---|---|
| Operator application (for example, My Tele2, My Beeline) | Automatic setup of APNs and services | Requires installation of additional software |
| APN Backup & Restore (from Google Play) | Save and restore APN settings | Does not update the parameters automatically |
| Engineering menu (#4636###) | Manual selection of network and standards | Difficult for beginners, risk of disruption |
| Firmware for Global MIUI | Full compatibility with Russian operators | Requires unlocking the loader |
For most users, the best option is to disable the SIM activation service and install the official application of their operator, for example, MTS Connect or Beeline My automatically configure APN and even offer bonuses for use.