How to Completely Disable VoWiFi on a Xiaomi Redmi 9C Smartphone: 5 Proven Methods

Technology VoWiFi (Voice over Wi-Fi) allows you to make calls over Wi-Fi networks, which is useful in areas with poor mobile coverage. However, Xiaomi Redmi 9C This feature sometimes works erratically: calls are dropped, the battery drains quickly, or network connection issues occur. If you're experiencing these issues or simply want to disable VoWiFi to save battery life, these instructions will help you do it correctly.

Many users confuse VoWiFi with VoLTE (voice communication over 4G), but they are different technologies. Disabling one does not always affect the other, so it's important to understand which feature you're disabling. Redmi 9C with firmware MIUI 12–14 The path to settings may vary depending on the software version and regional settings. We'll cover all possible options, from the standard menu to hidden developer options.

Before you begin, check if your carrier supports VoWiFi. Some providers (e.g., MTS or Beeline) automatically activate this feature on compatible devices. If connection quality deteriorates after disabling, reset the settings or contact your carrier to clarify your plan.

1. Standard method: via SIM card settings

The easiest method is to use the built-in menu MIUIIt is suitable for most users and does not require root rights or technical knowledge.

Open the app Settings (gear icon) and go to the section:

Settings → SIM cards & mobile networks → [Select your SIM card] → Wi-Fi calling

Here you will see a switch VoWiFi. Move it into position OffIf this option is missing, your operator doesn't support the technology or it's disabled at the firmware level.

On some versions MIUI the path may look different:

• 📱 Settings → Connections and Sharing → SIM cards → [SIM number] → Additional settings → VoWiFi
• 🔄 If there is no switch, try updating the firmware or contact your operator.
• ⚡ In rare cases, the item is hidden - then the method from the next section will help.

⚠️ Attention: On Redmi 9C with firmware MIUI Global Sometimes settings are reset after an update. If VoWiFi turns on automatically, repeat the process or use the alternative methods in this article.

2. Alternative method: via the developer menu

If the standard method doesn't work, try disabling VoWiFi via developer modeThis method requires activating hidden settings, but does not affect the warranty.

First, enable developer mode:

1. Go to Settings → About phone.
2. Click on the item 7 times in a row MIUI version (a notification will appear saying "You have become a developer").
3. Return to the main settings menu and open the new section For developers.

Now find the settings related to VoWiFi:

• 🔍 In the search bar, enter wifi calling or VoWiFi.
• 📵 Disable all the switches you find (e.g. Wi-Fi Calling or IMS over Wi-Fi).
• 🔄 Restart your phone to apply the changes.

If there is no direct mention of VoWiFi in the developer menu, try disabling it. IMS (IP Multimedia Subsystem) is the protocol that powers the technology. To do this:

For Developers → Mobile Network → Enable/Disable IMS

⚠️ Warning: Disconnection IMS may affect operation VoLTE and SMS via Wi-Fi. If you stop receiving messages after this, please reset the settings.

What is IMS and why is it better not to touch it unless necessary?

IMS (IP Multimedia Subsystem) is a standard for transmitting voice and video over IP networks. Disabling it can disrupt not only VoWiFi but also other operator services, such as RCS messaging or video calls. If you're unsure about the consequences, use the standard VoWiFi disable feature in your SIM card settings.

3. Disabling via operator USSD commands

Some operators allow you to control VoWiFi using USSD codesThis is convenient if you don't have access to your phone's settings or they are locked.

Try the following commands (type them in the app Telephone like a regular number and press call):

After entering the code, you will receive an SMS or notification confirming successful deactivation. If the command doesn't work:

• 📞 Check with your operator for the current code (they may change).
• 🔄 Restart your phone and try again.
• 📌 Check if your plan supports VoWiFi (for example, MTS This is not available on all tariffs).

⚠️ Please note: USSD commands may deduct funds from your balance (usually 1–3 rubles per request). Please check the rates on your operator's website before using them.

4. Reset network settings (last resort)

If VoWiFi stubbornly turns on by itself or its settings are inaccessible, it will help reset network settingsThis method deletes all saved Wi-Fi networks, passwords, and mobile settings, but does not affect personal data.

Instructions:

1. Open Settings → SIM cards and mobile networks.
2. Select Resetting mobile network settings (or Reset Wi-Fi, mobile network, and Bluetooth).
3. Confirm the action and wait for the phone to reboot.

After reset:

• 🔄 VoWiFi will be disabled automatically (if not activated by your operator).
• 📶 You will have to reconnect to all Wi-Fi networks.
• 📵 You may need to manually select the network mode (4G/3G/2G) in the SIM card settings.

Important: On some MIUI versions, mobile internet access may be lost after a reset. In this case, go to Settings → SIM cards → Access point name (APN) and select the operator profile manually.

5. Checking the result and troubleshooting

After disabling VoWiFi, make sure the feature is truly disabled. To do this:

• 📞 Call another number and check if the call goes through the mobile network (the icon in the status bar should disappear) VoWiFi or Wi-Fi Calling).
• 📊 Open Settings → SIM cards → SIM card status and check the VoWiFi status.
• 🔋 Track your battery consumption throughout the day - if your phone previously drained quickly due to VoWiFi, its battery life should now increase.

If VoWiFi is still active:

1. Check if the feature is enabled at the operator level (sometimes it is activated automatically when connecting to Wi-Fi).
2. Update your phone's firmware to the latest version MIUI — New builds often fix VoWiFi bugs.
3. Contact support Xiaomi or an operator with a request to disable the service on the provider's side.

If incoming calls disappear after disabling VoWiFi:

• 📵 Make sure you haven't accidentally turned it off VoLTE (voice communication via 4G).
• 🔄 Switch your phone to standby mode 3G only in the network settings (sometimes this helps to restore the connection).
• 📡 Check your mobile network coverage in your area - the problem may not be VoWiFi, but a weak signal.

6. Common mistakes and how to avoid them

When disabling VoWiFi, users often encounter common problems. Here's how to prevent them:

Error 1: After disabling VoWiFi, mobile internet disappeared.

• 🔧 Solution: Go to Settings → SIM cards → Access point name (APN) and select the operator profile manually.
• 📡 If that doesn't help, restart your phone or enable/disable airplane mode.

Error 2: VoWiFi turns on automatically after reboot.

• 🔧 Solution: This is typical for firmware MIUI Global. Try updating the software or disable automatic settings updates in Settings → About phone → System update.
• 📵 If the problem persists, use your operator's USSD commands to force a shutdown.

Error 3: I can't find VoWiFi settings in the menu.

• 🔧 Solution: Your carrier may not support this technology. Check the official website or call the support number.
• 📱 If the phone was purchased abroad, check the regional settings: go to Settings → Advanced → Region and select Russia.

⚠️ Attention: On Redmi 9C with custom firmware (for example, LineageOS) The path to the VoWiFi settings may differ. In this case, use universal methods: USSD commands or resetting network settings.

FAQ: Answers to Frequently Asked Questions

❓ VoWiFi is disabled, but the icon remains in the status bar. What should I do?

This could be a visual bug. MIUI. Try:

1. Restart your phone.
2. Turn on/off airplane mode.
3. Update your firmware to the latest version.

If the icon doesn't disappear, it doesn't mean VoWiFi is working. Check the actual status via ##4636## (test menu).

❓ Is it possible to disable VoWiFi only for a specific Wi-Fi network?

No, on Redmi 9C VoWiFi works globally: either for all networks or for none. However, you can:

• Disable automatic connection to unnecessary Wi-Fi networks in Settings → Wi-Fi.
• Use mode Mobile network only in the SIM card settings when connected to the problematic Wi-Fi.

❓ Will VoLTE work if I disable VoWiFi?

Yes, VoLTE And VoWiFi — these are different technologies. Disabling one does not affect the other. However, if you deactivate IMS In the developer menu, VoLTE may also stop working. In this case:

1. Return settings IMS to its original state.
2. Disable only VoWiFi through the standard SIM card menu.

❓ How do I know if my carrier supports VoWiFi?

Verification methods:

• Call the operator and clarify (for example, MTS: 0890, Beeline: 0611).
• Check the list of supported devices on the operator's website (for example, Redmi 9C should be on the list of compatible smartphones).
• Enter the USSD command to check the status (see the table in section 3).

If your carrier supports VoWiFi, but your phone doesn't have the settings, update your firmware or contact support. Xiaomi.

❓ After disabling VoWiFi, my connection quality has deteriorated. What should I do?

Possible causes and solutions:

• 📶 Weak mobile network signal: VoWiFi may have compensated for poor coverage. Try using VoWiFi again or switch to 3G (in your SIM card settings).
• 📵 VoLTE is disabled: Check the settings in SIM Cards → Calling over 4G (VoLTE).
• 🔧 SIM card failure: Reinstall the SIM card or contact your operator for a replacement.

If the problem persists, it may not be related to VoWiFi. Check your network settings or try a different SIM card.