How to Make Permanent 4G on Xiaomi: The Complete Guide

Xiaomi smartphone owners often face a situation where the device spontaneously switches from high-speed LTE to outdated 3G or even 2G. This happens even in areas of confident reception, which leads to a sharp drop in Internet speed and problems with data transfer. The reason lies in the aggressive algorithms of power saving system MIUI and the features of the modem, which tries to save battery power, sacrificing the quality of the connection.

To address this problem, it is necessary to force the network to prioritize the fourth generation standard. Forced fixation does not mean a complete ban on other standards, but gives the system a clear signal about what type of communication is preferred, in most cases, this allows you to stabilize the connection and remove the constant jumps in the network indicator in the status bar.

The setup procedure may vary depending on the version of the Android operating system and the HyperOS shell. Some methods require special codes, others require access to the engineering menu. It is important to understand that interference with the settings of the radio module is safe if you act according to the instructions, but resetting network settings may be necessary to apply changes.

Causes of unstable connection on Xiaomi smartphones

The main reason for the unstable operation of the mobile Internet is the dynamic switching of communication standards. The smartphone constantly scans the airwaves for a base station with a stronger signal, and if 3G turns out to be more powerful, the system instantly switches to it. Handover algorithms in Xiaomi firmware are often configured with a priority on the stability of voice communication, rather than data speed.

Another factor is the physical location of the operator’s towers. In border areas where the 4G signal is weak, the phone will cling to the longer-range but slower 3G. The critical point is that without manual fixation, the smartphone will endlessly search for the “best” signal, draining the battery and creating the illusion of poor communication.

Also worth considering is overheating, which is a modem that can reduce performance or temporarily shut down high-frequency LTE bands to prevent critical heating, a protective mechanism that cannot be turned off software without risking damage to hardware.

⚠️ Attention: Forced retention 4G in the zone of very weak signal can lead to complete lack of communication, as the phone will stop switching to available 3G voice-call.

Basic Network Priority setting in the menu

The first step should always be to set up the standard interface, which is the most secure method, which does not require root rights or special knowledge, and you need to go to the settings section, where you manage SIM cards and mobile networks.

Find the network type. In modern versions of MIUI, it is often hidden or has limited functionality. However, the basic choice between "Prefer LTE" and "Auto" can significantly affect the modem behavior. If the standard switch does not work, move to deeper settings.

• 📱 Open Settings and go to the section SIM-maps and mobile networks.
• 📡 Select your SIM card and click on Network Type or Preferred Network Type.
• ⚙️ Choose the option to Prefer LTE or LTE/TD-SCDMA/GSM.

If the menu does not have the option of selecting a specific standard, the system relies on automatic operator settings, in which case the standard methods are ineffective, and you need to use hidden engineering menus or special applications to control the modem.

Using the Engineering Menu to Fix 4G

The most effective way to get Xiaomi to keep 4G is to log into the engineering menu through a special code, which allows you to control the parameters of the radio module directly, bypassing the limitations of the user interface, and to access it using standard code that runs on most MediaTek and Qualcomm chipsets.

You need to open the Phone app and dial ##4636#. Once you enter the last digit, the hidden testing menu will automatically open, and if the code doesn't work, your firmware version may block that access, and you'll need third-party utilities.

In the menu that opens, select Phone Information. Find a drop-down list called Set Preferred Network Type. Here's a huge list of combinations of communication standards, and choosing the right one is key.

Select a mode that contains LTE and GSM. The "LTE Only" mode is highly undesirable, since in this case you will not be able to receive incoming calls if the operator does not support VoLTE technology. The optimal choice is the combined mode, where LTE is first in the list of priorities.

Alternative methods through applications and ADB

If the engineering menu is unavailable or resets after rebooting, you can use third-party apps from Google Play. Programs like Force LTE Only (4G/5G) or NetMonster allow you to change the modem parameters through system calls similar to those used in the engineering menu.

For advanced users, a debugging method is available via ADB (Android Debug Bridge), and by connecting a smartphone to a computer, you can send a command to change the configuration of the radio module, which requires the developer mode on and the SDK platform installed on the PC.

adb shell service call phone 3 s16 "LTE_ONLY"

However, the use ADB Teams can be challenging for beginners and require cable connection every time. Market applications operate autonomously, but require special permissions through the accessibility menu or ADB-first-run.

The impact of VoLTE and IMS technology on stability

VoLTE (Voice over LTE) technology allows voice transmission in 4G data packets, which should theoretically eliminate the need to switch to 3G during a conversation. On Xiaomi smartphones, support for this feature is often hidden or depends on the firmware region.

If your carrier supports VoLTE but the feature is not active, the phone will reset the network to the 3G When you call in or out, you need to activate the call to avoid this. IMS-In some cases, this requires editing the system file. carrier_policy.xml or use of special activation codes.

Activation of VoLTE not only improves the quality of communication, but also allows you to stay on the network. 4G This is especially important for gamers and those who use the navigator while they're calling. IMS-The phone will not physically hold the profile. 4G voice calls in most regions.

⚠️ Warning: Forced activation of VoLTE on unsupported carriers may result in you being unable to make calls while remaining only with the internet.

Resetting network settings and operator selection

Sometimes the problem is not with the phone's settings, but with accumulated network configuration errors, resetting the network settings returns all modem parameters to factory values, removing stored APN access points and base station cache.

Resets can be done via Settings menu → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth. After this procedure, the phone will re-register in the operator’s network, which often solves the problem of “sticking” on 3G.

It also makes sense to manually choose a carrier instead of an automatic mode. In the network selection menu, wait until the search is over and select your carrier from the list, which will prevent the phone from trying to register with roaming or neighboring towers with the worst signal.

• 🔄 Go to Settings. → SIM-maps and mobile networks.
• 📡 Click Operator Choice and turn off the switch automatically.
• ✅ Wait for the search and select your operator manually.

Once manually selected, the phone will ignore other available networks, even if their signal is more powerful, which helps in border areas where the towers of different operators are located close together.

💡

If the Internet and MMS are lost after resetting your network, don't panic. Go to the APN settings and click "Restore Default" or create a new point with your operator's settings.

Frequent Questions and Challenges (FAQ)

💡

The most reliable way to fix 4G is a combination of manual operator selection, VoLTE enabled and LTE/TD-SCDMA/GSM prioritized via the engineering menu.