Many Xiaomi and Redmi smartphone owners face the unpleasant situation of a conversation with the interlocutor being cut off after exactly 4 hours or, in some cases, after 120 minutes.This is not a hardware defect or a defect of your device.In fact, it is a software restriction set by the carrier or factory firmware settings to prevent the line from hanging.
However, if you have long conversations, online consultations or just like long conversations with loved ones, a standard timeout becomes a serious problem. Fortunately, the Android operating system, which runs the MIUI or HyperOS shell, has the ability to change this setting. In this article, we will discuss in detail what methods exist to circumvent restrictions and how to configure your smartphone for more comfortable communication.
There are several ways to solve this problem: from simple USSD-It's important to understand that the effectiveness of each method depends on your region, phone model and mobile operator policy. Some settings may be hidden from the average user, but we'll show you how to access them safely.
Reasons for Automatic Call Resetting
Before settings, you need to understand the nature of the limits, most often the limit of 4 hours (14400 seconds) or 2 hours is set directly on the cellular operator side, this is done in order to unload the network and automatically terminate the “hangover” connections that can occur due to technical failures or loss of signal in the “dead zones”.
The second reason may be the device itself. Xiaomi firmware sometimes has a default timer activated to save battery power or prevent the microphone from accidentally leaving the microphone on. Android’s engineering menu contains hidden parameters that regulate the duration of the connection, and it is their change that allows you to bypass standard limits.
⚠️ Attention: Change of settings in the engineering menu requires caution. Do not change the values of parameters in which you are not sure, as this may lead to incorrect operation of the communication module.
Also, it’s worth considering that some current models with VoLTE and 5G support may have different voice protocols, so if your carrier uses specific network settings, the software time extension may not work and the limit will remain at the base station level.
Checking the current status through USSD-code
The easiest and safest way to know the current status of a call timer is to use special dialing codes, which allow you to ask the network how many seconds it takes to automatically reset, and you don't need root rights or a computer connection.
To check, open the standard "caller" and enter the following character set: *#61#. After pressing the call button, the information window will appear on the screen, it will indicate the number to which the call is being forwarded and the delay time. If it indicates a value of 14400 seconds (or 240 minutes), then the standard 4-hour limit is set.
The alternative is to use the ##002# code. This command is designed to cancel all redirects, but often it also resets timers if they were set erroneously. However, it is to increase the limit that we will need more complex actions described in the following sections.
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Before making any changes, write down the current values of the parameters so that, if necessary, you can return to the original settings.
Change the call time limit through the engineering menu
The most effective way to increase talk time on Xiaomi is to use an engineering menu, which provides access to deep modem settings, and uses a special code to log in that works on most MediaTek and Qualcomm devices.
Enter the dialer code ##4636##. If the menu opens, select Phone Information. Scroll down to Call Settings. There may be a Set Call Timer option or similar. If you don't, try entering ##3646633##, which opens the full Engineering Mode.
In the full engineering menu, you can navigate through tabs. You go to Telephony, then you can select Call Control or Call Setting. Find the option associated with the call duration (Call Duration Limit). By default, it can be 14400 seconds. Change it to the maximum available (often 999999) or 0 if the system interprets zero as "without restrictions."
☑️ Preparing for changing settings
When you change the setting, make sure to press the Set or Apple button. Then restart the device. Check the result by making a test call or using it again. USSD-If the values are still there, then the method worked.
⚠️ Note: Some global versions of the firmware MIUI Entering the engineering menu through codes may be blocked by the manufacturer, in which case you will need to use third-party applications.
Use of applications to change region and codes
If standard codes don’t work, as is often the case with new Xiaomi HyperOS models, specialized apps from the Google Play Market come to the rescue, allowing you to emulate engineering commands or open hidden Android activity menus.
One popular tool is the Xiaomi Engineer Mode app or universal utilities like Activity Launcher. Once you install it, look for a process called com.android.phone on the activity list, and look for items that contain the words "Engineering," "MMI," or "Call Settings."
There are also applications for changing the region (CIT), Changing the region from Russia to India or Singapore sometimes changes the set of available features. USSD-commands and modem settings, allowing you to bypass the regional restrictions of the operator.
| Method | Difficulty | Efficiency | Risk of failure |
|---|---|---|---|
| USSD codes (*#61#) | Low. | Medium | Minimum |
| Engineering menu(s) | Medium | Tall. | Medium. |
| Third-party annexes | Medium | Tall. | Medium. |
| Root rights and fashion | Tall. | Maximum | High-pitched |
Why can codes not work?
Problems with VoLTE and HD-vocally
Today's networks are moving to VoLTE (Voice over LTE), which transmits voice as a data stream over the Internet protocol. This improves sound quality, but makes its own adjustments to the operation of timers. Limits in VoLTE are often tighter tied to the operator's data sessions, and it is more difficult to change them programmatically on the phone.
If you notice that after turning on VoLTE calls began to stop more often, try temporarily disabling this feature. → SIM-maps and mobile networks → Using VoLTE.Disable can return timer management to standard level GSM/3G Connections where codes are more reliable.
However, it is not always advisable to abandon VoLTE, since the quality of communication in 4G/5G networks is much higher.The best solution is to contact your operator’s support team with a request to increase the network-side conversation time limit.
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VoLTE technology transmits voice over an internet channel, so restrictions are often set by the operator's server rather than the phone.
Additional energy saving settings
Sometimes the call is interrupted not because of the timer, but because of the aggressive power saving system MIUI. If the phone decides that the application "Phone" consumes too much resources or is in the background for too long, it can forcefully terminate the process.
To rule out this factor, go to Settings → Battery and Performance. Search the apps for Phone and Google Play Services. Set the No Limits mode, which will prevent the system from killing the call process even when you are active for a long time.
Also check the screen settings. If the screen is set to go out too short, the phone may go into deep sleep, which sometimes breaks the unstable connection. Increase the screen timeout to 2-5 minutes during important conversations.
⚠️ Warning: No Limits mode increases battery consumption. Use it selectively only if the problem with the call interruption is really energy saving.
What to do if nothing helps
In rare cases, neither the engineering menu, nor the codes, nor the settings work, which means that the lock is set at the equipment level of your operator's base station and cannot be changed from the subscriber's device, in which case the only way out is to change the tariff plan or move to an operator with a more loyal policy.
It's also worth checking if you have any third-party "caller" installed from the app store.The standard MIUI Dialer app is more stable. If you're using Google Phone or Truecaller, try going back to Xiaomi's stock app for a check.
Remember that the maximum possible continuous call time on most networks is 4 hours, and it is technically impossible to get around this limit without operator intervention because of the communication protocols.