Modern Xiaomi smartphones running under the control of shells MIUI or the new HyperOS, by default activate many network functions to improve the user experience. LTE), It's a high-quality voice transmission service that can be used over fourth-generation networks, but not all regions have operators that support it correctly, and sometimes it can cause conflicts with other regions. SIM-card or speed up battery discharge.
Users often experience a situation where the HD icon is constantly on, but the quality of communication leaves much to be desired, or the interlocutor simply does not hear you during the conversation, in such cases, it becomes necessary to forcefully deactivate the option, you can do this through the standard settings menu, although in recent versions of firmware developers sometimes hide this switch deeper into the system.
In this article, we will take a look at all the ways to manage voice calls over LTE, where to look for hidden engineer menus, how to use codes to access test modes, and what to do if the slider is not in the settings, and understanding these processes will help you optimize the operation of your device’s communication module.
Why you might need to shut down VoLTE
VoLTE is designed to improve communication quality, but in practice, it is unstable in some carrier networks. The main reason why users tend to turn this feature off is coverage problems. If your 4G signal is weak and constantly jumps, the phone will try to hold the connection for a voice call, which will lead to constant interruptions or inability to reach.
Another important aspect is power consumption. A communication module that constantly supports a high-resolution voice channel can consume more power than when running in standard 3G or 2G mode. If you notice that your Xiaomi Redmi or Poco quickly discharges in standby mode, and in battery statistics, the “Mobile Network” leads, then the experiment with turning off VoLTE can prolong battery life.
⚠️ Warning: Disabling VoLTE may cause your Internet channel to switch to the Internet during a conversation 3G or (EDGE). This means that the speed of the Internet during the call will be significantly reduced, and video calls in instant messengers can be interrupted.
It is also important to consider compatibility with SIM-Old SIM cards that haven't been replaced with new ones with support USIM, In these cases, the phone may not make any outgoing calls at all until you return the settings to their original state or replace the plastic from the operator.
Standard method through settings SIM-map
The simplest and most secure method of managing the feature is in the phone's basic settings menu. The interface may vary slightly depending on the shell version, but the logic remains the same across all the brand's devices. You don't need superuser rights or a computer connection.
To start, open the Settings app and find the section that handles wireless networks. In current software builds, it's often called the "Settings" app "SIM-maps and mobile networks. This is where all the data and voice parameters are concentrated.
☑️ Algorithm of action
Once you log in, select the SIM card that you want to change (if there are two) and find an item called "Use VoLTE" or "LTE Calls." If the switch is active, just click on it to turn gray. In some cases, the system may require the device to restart to apply the changes.
If you're using Xiaomi Black Edition or global firmware, the path may look a little different. Sometimes the option is hidden inside the optional submenu "Operator Settings" or "Advanced." Be careful when searching, as the translation of terms can vary.
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If you don’t see the VoLTE switch on the menu SIM-Your phone card, your carrier may not have certified this feature for your phone model, in which case the standard method won't work.
Use of the Engineering Menu for Advanced Users
When standard settings are unavailable or blocked by the operator, the utility menu comes to the rescue, which is a hidden part of the system designed for testing equipment by plant engineers, where you can force various communication protocols, including VoLTE, to be turned on or off.
To enter this mode, a special code is used, which is typed in the Phone app as a regular number. The most universal code for Xiaomi devices is ##4636#. Once you enter the last digit, the menu should open automatically. If this does not happen, your version of the shell may block access and you will need third-party applications.
In the list that opens, select Phone Information. Scroll down to Set your preferred network type. Here you will see a drop-down list with many abbreviations. You will need to select an option that does not mention IMS or VoLTE, such as "LTE Only" (LTE only for data, but calls over 3G) or "WCDMA preferred."
| Network mode | Description | Impact on VoLTE |
|---|---|---|
| NR/LTE/GSM | Automatic selection of 5G/4G/2G | VoLTE is enabled by default |
| LTE Only | Only 4G networks. | Calls may not be made without VoLTE |
| WCDMA Only | Only 3G networks. | VoLTE is completely disconnected |
| GSM Only | Only 2G networks. | Maximum compatibility, no VoLTE |
Be careful when choosing LTE Only mode. In this mode, the phone will only catch 4G. If there is no LTE in your coverage area but there is 3G, you will lose communication completely, since the phone will not be able to switch to the lower standard for voice calls.
⚠️ Warning: Changes to the engineering menu are reset after a full phone restart or flight in some software versions. If you need a permanent shutdown, it is better to use the method with the activation code for hidden functions.
What if the code doesn't work?
Activation of hidden menus through activation codes
In the latest versions MIUI 14 and HyperOS, the engineering menu is often closed, and you can use special switches to unlock hidden switches in the standard interface. USSD-This method is safe and does not require the installation of additional software.
Dialer code ##86583##. If all goes well, you will see a pop-up notification saying "VoLTE carrier check was disabled" (or similar message saying operator check is disabled). SIM-The card should appear slider to control VoLTE.
Some regions and models, especially Chinese versions of smartphones, may require a different code: ##869434##.It is designed to disable checking for regional restrictions.
If none of the codes helped, perhaps your hardware modem does not support manual control of this setting, or the carrier has rigidly blocked the ability to change the settings at the profile level. SIM-In this case, there is only a change of cards. SIM-map.
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Activation codes only work at the programming interface level, and they don't change the modem settings forever, but they allow you to access hidden switches in the settings menu.
Solving the problems with two SIM-map
Owners of devices with two active SIM-And when one card is busy talking, the other card can go into "Unavailable" mode or lose the network if it's not configured correctly.
In the settings "SIM-Maps and mobile networks" is a section "Mode of operation of two SIM-Here, we recommend selecting an option that allows both numbers to stay online. 4G However, if you turn off VoLTE on one of the cards, make sure that the second card is given the right data priority.
- 📱 Make sure to take calls to the second. SIM" Active if you want to keep your phone on the first line.
- 📡 When you turn off VoLTE on the main SIM, check if the second SIM has switched to mode. 2G, which may lead to loss SMS.
- 🔄 If the Internet is lost after the changes, try to switch the "Mobile Internet" to another one. SIM-map and back through the quick access panel.
Sometimes it helps to temporarily retrieve one of the SIM cards, take out the second card, set up the first card properly, turn off the phone, insert the second one back in and turn on the device, and that forces the system to re-register with new parameters.
Influence of the firmware version and region on settings
The behavior of VoLTE is directly dependent on the regional version of the firmware (Global, EU, China, Russia). In the Chinese versions of MIUI, the settings can be more detailed, but lack localization for European operators. Global versions, by contrast, often have a stripped down menu, where many items are hidden.
If you upgrade to HyperOS, note that Google and Xiaomi are implementing new security standards that can block manual changes to network protocols, in which case even the engineering menu may not give the desired result without root rights.
Regional settings also affect the list of available carriers. If you use a phone brought from another country, your operator may not be on the menu in the list of VoLTE supporters. In this case, the function is disabled automatically by the system, or, conversely, it is turned on forcibly and does not turn off.
⚠️ Warning: Flashing your phone from Global to China for enhanced network settings could lead to banking apps and work NFC. Weigh the risks before changing the device region.