Many owners of Xiaomi, Redmi and Poco smartphones face a situation where the device spontaneously switches to 3G or even 2G in the area of unreliable reception, which leads to connection breaks, a drop in page load speeds and the inability to use messengers properly. Often the operator can not provide stable LTE coverage in all corners of the area, and the phone, trying to save energy or catch any signal, switches to outdated communication standards.
Forced 4G mode allows you to lock the communication module at LTE frequencies, ignoring weaker 2G and 3G signals. This is especially true for users who use a smartphone as an access point for Wi-Fi or need a stable VoIP connection during travel. However, it is worthwhile to understand that in the “deaf” areas where LTE is completely absent, the phone will simply lose the network, as switching to 3G it will be forbidden software.
In this article, we’ll look at all the available methods for network fixation, from standard Android settings to the use of engineering menus and special applications. It’s important to remember that the interfaces of the MIUI and HyperOS shells may vary slightly depending on the firmware version, but the basic principles remain the same throughout the Xiaomi ecosystem.
Standard settings of the preferred network type
The first and safest step is to check the standard settings of the smartphone. In most cases, the system itself suggests choosing a priority network type, although an explicit button is "Only" 4G» You may not have a regular menu. You need to go to Settings, then select the item. SIM-Maps and mobile networks. You should choose active networks. SIM-map, if there are two, and find the network type or preferred network type.
The options that open up usually include combinations like “LTE Preferably,” “LTE/WCDMA/GSM,” or “5G/LTE/WCDMA/GSM.” Choosing a variant marked “Preferably” means that the phone will try to hold on to 4G, but if the signal is weakened strongly, it will still switch to 3G. This is a balanced mode that provides the best compromise between speed and coverage. If your goal is simply to improve communication quality without drastic measures, this may be enough.
If there is no option in the list, “Only” LTE» or «LTE Only, and the phone is holding on to 3G, You'll need to use more advanced customization tools. MIUI It often hides extreme options for switching the radio module so that the inexperienced user does not remain without communication. USSD-code.
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If you’re roaming, a forced 4G switch can help avoid costly 2G/3G affiliate connections, but make sure your fare supports LTE in your host country.
Using the CIT Engineering Menu to Fix Networks
The most reliable way to get Xiaomi to work exclusively in 4G mode is using the CIT (Customer Integration Test) engineering menu, a hidden part of the system designed for testing hardware components by engineers in the factory, accessed through a set of special code in the Phone application. Enter the command ##6484## or ##4636#. If the first code opens the full test menu, find the Sim Card Status or Phone Information item there.
Inside the Phone Information menu, scroll down to Set Preferred Network Type. This drop-down list contains many technical indications of the radio modes. You need to find the LTE Only option. Once you select this item, the smartphone will force you to switch to 4G. If you are in LTE coverage, the network icon will change, and the phone will no longer see the 3G and 2G towers.
⚠️ Attention: Being on mode LTE Only, you may lose the ability to make regular voice calls if your carrier does not support VoLTE (Voice over) technology. LTE) or if it is not activated on your SIM-In this case, incoming calls will not pass, and outgoing ones will be dropped.
To return to normal mode, you need to go back to this menu and select an option. LTE/WCDMA/GSM (auto connect) or similar, containing the word "auto." Don't be afraid if, after selecting the mode, LTE Only the signal level icon is missing – it’s normal if there’s no coverage at the current point 4G. It is enough to go outside or move to the zone of confident reception, and the connection will be restored.
☑️ Pre-insertion check LTE Only
Alternative methods through Activity Launcher
New versions of HyperOS shell and new updates MIUI Access to the engineering menu through codes can be blocked or redirected to standard settings, in which case comes to the rescue system application Activity Launcher (or its analogues), which allows you to run hidden Android activities. Download the app from a trusted source (e.g. Google Play or a trusted app). APK-file) and run it.
In the app search box, type in the word “radio” or “network.” You need to find an activity called RadioInfo or Testing that refers to the system app Settings or Phone. After you go down this path, you'll be in the same menu that's called by the codes, but you don't have to type them in. LTE Only.
The good thing about this is that you can put a shortcut to access this menu quickly on your desktop. By creating a RadioInfo activity shortcut, you can switch between network modes in one click, which is convenient when you move between areas with different coverage. However, be careful: some system activities can behave unstable on custom firmware.
Why is the LTE Only item missing?
Comparison of radio module operation modes
Understanding the differences between network modes helps avoid communication problems. Users often choose LTE Only without realizing the consequences for voice communication. Below is a table that will help you understand the main types of networks and their impact on the performance of Xiaomi smartphone.
| Network mode | Description | Impact on calls | Recommendation |
|---|---|---|---|
| LTE/WCDMA/GSM (auto) | Automatic selection of the best signal | Calls are stable. | Daily use |
| LTE Only | Only 4G, Ignoring 2G/3G | Only if you have VoLTE | For the mobile Internet |
| WCDMA Only | Only 3G networks. | Calls are working. | In areas without 4G |
| GSM Only | 2G only (EDGE/GPRS) | Calls are working, there is no internet | For maximum autonomy |
As you can see from the table, LTE Only is the riskiest mode for voice communication. If your carrier hasn't implemented VoLTE (voice over 4G), then switching to this mode, the phone simply won't be able to install a voice channel. In today's networks of large cities, VoLTE works well, but in regions the situation may be different.
Also worth noting is the effect of modes on autonomy: Searching for a network in Auto mode consumes more energy than a fixed mode if the signal is unstable. The phone constantly scans the airwaves, trying to find the best tower. Fixing on 4G in the confident reception zone can even save battery power, since the module will not waste resources on constant search and switching between standards.
Solving VoLTE problems on Xiaomi
The key condition for comfortable use of the regime "Only" 4G» It's called VoLTE, and without it, your smartphone won't be able to make calls on the Internet. LTE. On Xiaomi and Redmi devices, it is common for the operator to support VoLTE, but the corresponding switch is hidden in the phone menu. To activate it, sometimes you just need to enter the code # #86583##, then in the settings. SIM-The card will appear in the item "Use VoLTE».
If the code didn’t work, you can try activating the function through the hidden menu described above (Sim Card Status item). Find the VoLTE Provisioned switch and turn it on. After the smartphone is restarted, the VoLTE or HD icon should appear in the status bar. The presence of this icon ensures that when LTE Only mode is turned on, you will remain available for voice calls.
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Without an active VoLTE icon in the status bar, enabling 4G Only will make it impossible to receive and make regular calls.
Even with VoLTE enabled, call quality depends on the quality of the Internet connection. If 4G speeds drop, the voice may be interrupted or disappear altogether, so in places with unstable LTE, it is better to return to automatic network selection mode so that the phone can use 3G for voice communication.
Possible problems and solutions
When using forced network settings, users may face a number of specific problems, the most common being total loss of communication (“No network”), which occurs if you turn on LTE Only in an area where 4G coverage is not physically available or temporarily unavailable due to tower work, in which case the phone will not be able to “roll back” to 3G, since it is forbidden to do so.
Another problem is that you can't receive SMS. Some mobile operators deliver service SMS and confirmation codes through 2G/3G channels, especially when roaming or congesting major networks. If you block these standards, codes from banks may or may not arrive late, and you need to temporarily return your standard network settings.
⚠️ Attention: When resetting network settings or flashing your smartphone, all changes in the engineering menu (LTE Only) will be reset to factory values. You will have to re-activate the desired mode after each complete reset.
If the phone starts to heat up or discharge rapidly after 4G, it may indicate that the device is at the edge of the coverage zone, or that constant search for a signal or working at the transmitter power limit in network lock mode creates a high load on the modem, in which case it is better to return to automatic network selection.