Modern Xiaomi smartphones, which run on Android and the MIUI or HyperOS shell, are automatically set to choose the type of network by default. This is convenient for most users who want to get the maximum speed where it is, and keep the connection where 4G signal is weak. However, in the realities of domestic telecom operators and dense urban development, automation often works incorrectly. The phone can cling to an overloaded 3G tower, negating a stable 4G, or constantly jumping between standards, which leads to connection breaks during calls or games.
Forced modem fixation on LTE Only (4G only) solves these problems, not only a way to get a more stable Internet, but also a way to save battery power, as the radio module stops wasting energy on constant search and switching between frequencies. Owners of budget models such as the Redmi Note or Poco M series often notice that manual network selection significantly improves interface responsiveness and page loading speed.
In this guide, we will discuss all the available ways to switch a smartphone to 4G mode only. We will cover both the standard system tools that are hidden from the average user, and more advanced methods through the engineering menu and third-party utilities. It is important to understand that interfering with the radio module requires care, but with the right approach it is safe for the device.
Why is the smartphone switching to 3G and what is the problem?
The main reason your Xiaomi is resetting a 4G connection to 3G or even EDGE is because of the architecture of today’s networks. LTE was originally designed as a data technology, not a voice. When you take an incoming call, the phone must either use VoLTE (Voice over LTE) technology or switch to the older 2G/3G standard for voice. If your carrier doesn’t support VoLTE in your region or in your phone settings, this feature is disabled, the device will forcefully lower the network priority.
In addition, the manual network selection algorithms in MIUI firmware are often set to maximum compatibility rather than maximum speed.The smartphone sees a weak 4G signal and, in order not to lose communication at all, switches to a longer-range but slower 3G. In poor coverage, this leads to the phone being stuck at low speed, even if you are on the move and after a minute the 4G signal would become excellent.
⚠️ Attention: Forced incorporation of the “Only” regime 4G" This may cause you to stop accepting regular voice calls if your carrier or plan does not support VoLTE technology. Incoming calls in this case will go immediately to voice mail or the subscriber will hear the beeps, and the screen of the smartphone will not display the incoming call.
4G frequencies (especially bands above 1800 MHz) are worse at bending obstacles and penetrating walls than 3G. If you are in a basement, deep mall room or in a remote rural area, rigid fixation on 4G can lead to a complete loss of signal (“No network”), whereas automatic mode would keep at least a slow but working Internet.
Using an engineering menu to select a network
The most reliable and built-in way to make a phone work exclusively in 4G mode is to use Android’s hidden engineering menu, which is designed to test hardware by engineers, but is also available to ordinary users. On Xiaomi smartphones, it is logged in through a special code in the Phone app.
To start, open a standard caller and dial ##4636##. If the code is entered correctly, the menu will open automatically, you don't need to press the call button. You'll see a list of test modes. We're interested in Phone Information. In some versions of MIUI firmware, this item may be hidden or unavailable without root rights, but it works on most global versions.
In the menu that opens, scroll down to Set Preferred Network Type, where you'll see a drop-down list with multiple options. You'll need to select an option that has the word LTE Only in its name. This is usually the lowest item on the list. Once you select this option, the network icon in the status bar may disappear for a second, and then the letter "H" or "4G" appears.
What if the code doesn't work?
Importantly, after a smartphone reboot, the settings in the engineering menu can be reset to the default value (usually LTE/TD-SCDMA/CDMA/EVDO/GSM/WCDMA). This is the normal behavior of the security system. Therefore, the LTE Only selection procedure will have to be repeated after each phone switch is turned off.
☑️ Check before changing network settings
Setup through a hidden menu SIM-map
If the classic engineering menu ##4636## on your Xiaomi doesn’t have the right options or doesn’t work properly, you can try an alternative way through the settings. SIM-This method is less well known, but often proves more stable on devices with MediaTek processors and some versions of Snapdragon.
Go to the smartphone settings and find the About section. Click on the Kernel Version or MIUI Version several times in a row until the CIT menu opens. However, a more direct route is to use the code ##3646633## (powered by MediaTek) or ##8378## (for some older models). If none of the codes worked, there is a universal way through the MTK Engineering Mode (required for MediaTek chips) app that can be downloaded from the app store.
In the Engineering Mode interface, you need to go to the Telephony -> Network Selecting tab. Here you will see a list of available network modes. Select Preferred Network Type and set the LTE Only value. The interface may differ depending on the Android version, but the logic remains the same: find the priority of the network and set the maximum available standard.
| Parameter | Default value | Recommended value for 4G | Impact on the battery |
|---|---|---|---|
| Type of network | Auto (LTE/WCDMA/GSM) | LTE Only | Reduces the cost |
| Data roaming | Off. | If necessary, | It doesn't. |
| VoLTE | On/Auto | Included (desirable) | Not much. |
| Networking | Automatic. | Manual (optional) | Reduces the cost |
After making the changes, be sure to restart the device so that the communication module applies the new parameters. If after the reboot the Internet is completely lost, and the network icon shows "R" or cross-out, then there is really no 4G coverage in your area, and the phone can not register with the network, in which case you will have to return the settings back.
Application of third-party applications for fixing LTE
For users who don’t want to mess with codes and engineering menus, or whose devices have blocked access to network system settings, there are specialized applications. The most popular and proven solution is Force LTE Only (4G/5G), which is available on Google Play Market and works on most Xiaomi smartphones without root rights.
The way these apps work is simple: they use the same system APIs as the engineering menu, but they provide a user-friendly interface with one big button. Once you install the app, launch it and click on "Method A: Android 10+" or "Method B: Android 11+," depending on your system version. The app will open the Usage system window where you can find "Phone Information" and select LTE Only.
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If the Force LTE Only app gives you an access error, try giving it permission to display over other windows or running USB debugging, although in most cases it works out of the box on Xiaomi.
The advantage of using third-party apps is that they can switch quickly, and many of them have a desktop widget that allows you to turn on 4G Only with one slipper before a game or an important messenger call, and just as quickly return everything back, which eliminates the need to type code every time or go into deep settings.
Be careful when choosing an in-store app, avoid questionable "Internet Accelerators" that promise miraculous speed gains, and you need the tools to control the radio module, and they can ask for broad permissions, which is a prerequisite for their operation, but requires trust in the developer.
The Impact of LTE Only on Autonomy and Communication
Switching to manual network selection has a direct impact on battery life. When the phone is in automatic mode, its radio module constantly scans the ether, evaluating the signal level of neighboring towers of different standards. This process, known as handover, requires energy. By fixing the network on 4G, you turn off this background search process, which can add up to 10-15% of screen time in unstable coverage.
But there's a downside to this: If the 4G signal in your zone is very weak (e.g., 1 dividing the scale), the phone will run to the limit, constantly amplifying the transmitter signal to connect to the remote tower, in which case the battery can run out even faster than in 3G mode, where the signal would be sure, so it makes sense to fix the network only where the 4G signal level is at least average.
Voice quality is also changing. As mentioned, without VoLTE, LTE Only calls are impossible. But even with VoLTE enabled, artifacts can occur: a delay in starting a conversation, a robotic voice, or cliffs if packet data is unstable. Unlike traditional voice, which is a priority in 2G/3G networks, voice in 4G is transmitted like normal Internet traffic and is susceptible to all its problems.
⚠️ Note: It is not recommended to use the "Only" mode. 4G" When traveling fast between cells, the phone may not have time to switch between towers within the same standard, which will lead to frequent network losses.
Solving IMEI and Network Recovery Issues
Sometimes, after experimenting with an engineering menu or a firmware failure, users are faced with the problem of disappearing. IMEI. The screen says, "No." SIM-cards" or "Valid IMEI", And the phone stops seeing the network at all, and this happens if the calibration data of the radio module is damaged during the setup process.
To restore your work, first try resetting your network settings. Go to Settings → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth. Press Reset and confirm action. This will return all network settings to factory values, including network type.
If a simple reset didn't help, deeper intervention may be needed.On Xiaomi devices with MediaTek processors, flashing often helps NV-Reconstruction or Reconstruction through the Program SP Flash Tool, but it requires backup. For regular users, the safest way is a full reset to the factory settings (Wipe All Data) through the Recovery menu, but first make sure you have a backup of important data.
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Returning to the factory network settings is the first and safest action for any definition issues. SIM-Disappearance of the signal after experimentation with the engineering menu.
In the rare cases where IMEI is lost completely (shown as 00000000 or null), you will need to visit a service center to flash certificates. Self-restore IMEI on modern versions of Android with a bootloader blocked by the manufacturer is almost impossible without special boxes and knowledge.