Xiaomi smartphone owners often notice a small but important VoLTE icon in the screen status bar, which can appear next to the network indicator or battery level, signaling the device’s transition to a new voice mode. For many users, it’s just a beautiful icon, but behind it hides a technology that dramatically changes the quality of telephone conversations in modern networks.
The appearance of this indicator means that your Xiaomi has successfully registered with the operator and is ready to transmit voice data through 4G LTE channels. This allows you to talk on the phone and simultaneously use high-speed Internet without switching to slower communication standards. If you see this icon, then the technical ability for high-quality calls (HD Voice) is active and working correctly.
In this article, we will explain in detail why this feature is needed, why it may not work on your device and how to properly configure network settings. Understanding the principles of VoLTE will help you not only improve communication quality, but also significantly save battery life, as constant network search becomes less energy-consuming.
VoLTE technology: the essence and advantages of work
VoLTE stands for Voice over LTE, which literally translates as Voice over LTE. Traditionally, fourth-generation (4G) networks were created solely for data transmission, and for voice calls, the phone was forced to switch to 2G or 3G standards when an incoming call arrived. This process took time, and the subscriber heard the beeps only after the device found the older generation network.
VoLTE technology allows voice to be transmitted as a normal data stream (packet transmission), similar to how messengers work, but with guaranteed priority in the operator's network. This provides instantaneous connection - the beeps are heard almost immediately after pressing the call button. In addition, voice is transmitted in HD, which makes the interlocutor's speech more clean, natural and devoid of characteristic noises and interruptions.
One of the key benefits is the ability to use the Internet and voice simultaneously. Without VoLTE activated during a conversation, the 4G icon on the Xiaomi screen changes to H+ or E, and the Internet speed drops to a minimum. With the feature enabled, you can download files, navigate on a map or watch high-quality video, continuing the conversation without losing speed.
⚠️ Note: VoLTE uses Internet traffic, but most modern operators do not charge these megabytes. Voice traffic is usually subtracted from packet minutes, not gigabytes, but it is recommended to clarify the terms of your tariff plan.
How to activate VoLTE on Xiaomi smartphones
Enabling LTE voice calls on Xiaomi and Redmi devices is usually automatic if the SIM card and operator support the technology, but in some cases, especially when using custom firmware or specific regions, the settings must be manually activated via an engineering menu or standard settings.
The first step should always be to check the basic settings in the phone menu. You need to make sure that the preferred 4G network type is selected in the mobile network section. If this option is set to 3G or 2G, the VoLTE icon will not appear, since the technology works exclusively on fourth-generation networks.
☑️ The VoLTE Incorporation Algorithm
For manual activation, go to Settings → SIM-Select the SIM card you want and find "Use VoLTE," if that's not on the visible menu, it might be hidden, so you can try typing a special code into the dialer: ##86583##. The message should be “VoLTE carrier check was” DISABLED», Paradoxically means that the operator check is disabled and the function is available for forced inclusion in the menu.
What if the code doesn't work?
Why the VoLTE icon doesn’t appear or disappears
The lack of a desirable icon on Xiaomi’s screen can be caused by a number of reasons, ranging from carrier-side issues to software failures in the MIUI shell. Often users are faced with a situation where the indicator burns in one part of the city and disappears in another, this is directly related to the coverage of the LTE network and the configuration of base stations.
Here are the main reasons why the function may not work:
- 📶 Lack of coverage 4G: In the weak signal zone, the phone can switch to 3G, where VoLTE is not supported.
- 📱 Old one. SIM-SIM cards released many years ago may not have a profile to work with new voice technologies.
- ⚙️ Region settings: In some regions (e.g. Russia or Europe), operators require additional certification, and Xiaomi hides the default switch.
- 🔄 Software Update: After updating the firmware, network settings could get lost, or, conversely, there was support for a new operator.
Also, consider that the phone itself must support the necessary bands of your carrier. Budget models Redmi or versions for the Chinese market (CN Version) may not have all the necessary frequencies for VoLTE from European or Russian providers.
⚠️ Note: If you have reflashed the phone to the global version (Global) ROM) In Chinese, the VoLTE icon may not appear due to a mismatch in the firmware, which is solved by editing configuration files or installing a patch.
VoLTE vs VoWiFi: What’s the Difference?
In addition to VoLTE, modern Xiaomi smartphones have another technology, VoWiFi (Voice over WiFi), which users often confuse the two concepts or icons, although they solve similar problems in different ways. Both standards are aimed at improving communication quality, but use different data channels.
VoLTE uses a cellular carrier network (base stations 4G), whereas VoWiFi transmits voice traffic through any available Wi-Fi connection, which is critical in places where cellular communication is poorly or not at all (basements, country houses, office centers with thick walls), but there is stable Wi-Fi.
Below is a table showing the key differences between technologies for better understanding:
| Parameter | VoLTE | VoWiFi |
|---|---|---|
| Transmission channel | 4G LTE cellular network | Internet (Wi-Fi router) |
| Dependence on operator | High (needs 4G coverage) | Low (only Wi-Fi required) |
| Sound quality | HD (high) | HD (depends on Internet speed) |
| Roaming work | Paid (international roaming) | Often free (as at home) |
It is important to note that the transition between these modes on modern Xiaomi devices is seamless. You can start the conversation while in the Wi-Fi zone, go outside, and the call will automatically switch to VoLTE without breaking the connection, if both functions are configured correctly.
The impact of technology on battery charge and the Internet
There is a common myth that VoLTE is running fast enough to significantly speed up battery drainage, and in fact, with stable 4G coverage, it even saves energy, because the phone doesn't have to constantly switch between 3G and 4G standards for incoming and outgoing calls, which is an energy-intensive process.
However, if the 4G signal is extremely weak and the phone is constantly trying to hold the LTE connection for VoLTE, battery consumption can actually increase. In such situations, the system itself can temporarily turn off the function or switch to 3G to save charge.
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For maximum battery savings in the low 4G signal zone, it is better to temporarily switch the network type to 3G, preferably if you do not need fast internet right now.
As for Internet traffic, voice calls via VoLTE use the IMS protocol. Telecom operators, as a rule, mark this traffic with a special marker and do not charge it, even if you run out of gigabytes. You will be able to call even if the mobile Internet balance is exhausted, the main thing is the availability of minutes in the tariff.
Frequent problems and ways to solve them
Despite the technology’s fine-tuning, Xiaomi users may experience periodic failures, such as an icon burning but no calls are made or the person can’t hear you, and the first thing to do is check whether Do Not Disturb mode or blocking unknown numbers that may conflict with call processing is activated.
Another common problem is time and date desynchronization, to ensure that security certificates and registrations work properly. IMS-The time on the phone must be accurate, make sure that the date and time settings automatically determine the time over the network.
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The first step for any communication problem is to reboot the smartphone, which re-registers the device in the operator's network and updates the network settings.
If nothing works, reset your network settings. This action won't delete your personal files, photos or contacts, but will return all your mobile, Wi-Fi and Bluetooth settings to factory values. → Connection and sharing → Reset Wi-Fi, mobile networks and Bluetooth.