Modern smartphones Xiaomi and Redmi are equipped with powerful communication modules, but it often happens that the device spontaneously switches to slower 3G or even 2G. This can occur in areas of unstable coverage, when overloading base stations or due to the peculiarities of the MIUI software. Users often face a situation when the Internet speed drops at the most inopportune moment, and standard methods such as turning on and off air mode cease to help.
The problem is relevant for owners of both budget models and flagships of the Xiaomi Mi or Xiaomi 13/14 series. The essence lies in the energy saving algorithms that the system activates by default. Forced network mode allows you to ignore these algorithms and make the modem look for an exclusively high-speed LTE signal. In this article, we will analyze all the available ways to fix the communication standard, from simple settings to using the engineering menu.
There are several layers of access to control of the network module, each of which requires different degrees of training. We will start with basic methods that are safe for any user, and gradually move on to more complex manipulation of system code. It is important to understand that imposing a certain communication standard can affect the quality of voice calls if the operator does not support VoLTE technology.
Basic Network Priority settings in MIUIThe first step should always be to check the standard Android settings. MIUI It has built-in functionality for choosing the type of network, but it is often hidden in the depth of the menu or works incorrectly due to software bugs. → SIM-Maps and mobile networks. This is where you pick active networks. SIM-If there are two, the network type menu opens. In the list that opens, select the option "Preferred". LTE" prefer LTE. This is a command to the system to try to keep the connection standard. 4G, But if there's no signal at all, she'll still drop it to the ground. 3G. If there is no such item on the list, it may be yours. SIM-The card is too old and does not support registration on fourth-generation networks, or the operator in your region does not provide such services. To do this, turn on the flight mode on 10-15 So you turn it off, and it forces the modem to re-enter the network and choose the best base station available. 4G+ It appears, but changes to H in a minute.+, So the problem is deeper, in the algorithms for switching between towers. 💡Before changing the network settings, make sure that SIM-map connected service 4G/LTE Sometimes the plan requires a separate activation of this option in your personal account.
Using an engineering menu to fix LTEIf the standard settings don't work, the engineering menu, the hidden interface for testing equipment, comes to the rescue. On Xiaomi smartphones, it is logged in through a standard phone typer ##4636##. If the menu does not open automatically after entering the last star, try the code ##3646633##, It's sometimes running on old firmware. Once you log in, you'll see a list of tests. We're interested in Phone Information. In the menu that opens, find the drop-down list "Set Preferred Network Type." That's where you can get a hard fix of the standard. You need to choose the option that contains the word LTE Only, usually. LTE Only or LTE/UMTS auto (PRL), But we need to do it for you. LTE Only. ⚠️ Attention: After the choice of the mode LTE Only your phone will stop receiving and making regular voice calls unless the operator uses VoLTE technology.You will only be able to call via instant messengers or receive incoming calls if they are supported via LTE. The change comes into effect instantly, and you'll see the network icon blink and lock in. 4G. However, there is a nuance: when leaving the coverage area LTE The phone will lose communication instead of switching to the phone. 3G. To return the call opportunity, remember to switch the setting back to LTE/TD-SCDMA/CDMA/WCDMA/GSM or similar combination regime. 📊 What was the result of the engineering menu?Worked right away / I had to search for the code / It didn't open at all / I'm afraid to break something
Secret codes for selecting frequency range The problem of unstable 4G Base stations can operate at different frequencies: 800 MHz (Band 20), 1800 MHz (Band 3), or 2600 MHz (Band 7), and a smartphone can cling to a distant tower with a low frequency that punches through walls but gives a low speed. To solve this problem, there is a special BandMode menu. Enter the dial menu and enter the code ##4636##, then select Phone Information. Scroll down to the BandMode button (or Select Band Mode). GSM, UMTS and LTE. Take the ticks off all ranges LTE, Except for the ones your operator uses in a particular location, for example, if you know that only Band 3 catches in your house, leave it alone. You can use analyzer apps like Cellular-Z or NetMonster to find out what frequency the nearest tower is running on. Once you've determined the right range (like Band 3 (1800), you force modem to switch only to that. This often gives you a boost in speed as the phone stops "throwing" between the towers. How do you know your Band? Download the Cellular-Z app, turn on the geolocation and look at the signal graph. The LTE bar will indicate the range number (Band).
Reset network settings and work with access points (APN)Sometimes the reason lies in the incorrect settings of the access point, which may have gone down after updating the firmware or switching from another operator, resetting network settings is a radical but effective method. It won’t delete your contacts or photos, but it will reset all Bluetooth, Wi-Fi and mobile settings to factory values. → Connection and sharing → Reset Wi-Fi, mobile networks and Bluetooth. Press Reset and confirm the action with the unlock code. Once the reset, the phone will prompt you to reset. SIM-Make sure that the mobile network settings activate the "Always search network" option or similar if it is available in your version. MIUI. It is also worth checking the parameters of the access point. APN. Go to Settings. → SIM-maps and mobile networks → Access points (APN). Click on the menu (three dots or reset button) and select Reset to the original. Make sure the protocol is in the settings of the selected access point. IPv4/IPv6. Sometimes only this parameter can be changed. IPv4 on IPv6 solves the problem of "sticking" on EDGE. ☑️ Checklist of network diagnostics Check coverage on operator map Make reset APNCheck it out. SIM Test the speed through Speedtest: 0 / 4
The impact of two SIM-stability-card 4GXiaomi smartphone owners often use two SIM-In low-end and mid-range models, the chipset may not physically support two cards simultaneously in mode. 4G. When one card is busy talking or transmitting data, the second card can be turned off or put into mode. 2G/3G You can check support for the call in the Settings menu. → SIM-maps and mobile networks. If there's no switch, "Use" 4G for data transfer for the second card, so your device supports 4G Only one slot (usually the first one) in which case, if you need constant internet, make sure that you have a good internet connection. SIM-card with a tariff for the Internet is inserted in the main slot. In addition, the presence of a second active SIM-The cards can interfere with reception, especially if both cards are in the same location, and the modem can try to sync with two different base stations at the same time, leading to instability. By temporarily disabling the second SIM in the settings, you can check if the signal becomes more stable (DSDS) Dual mode 4G Stability 4G Maximum Average (depending on the chip) High (on the flagships) Energy consumption Low High Internet speed Full May fall when calling on the 2nd SIM Stable effect on heating Minimum noticeable significant
Hardware reasons and operator choice Do not discount the physical condition SIM-Smartphone maps and antennas. SIM-cards issued 5-7 Years ago, they may not work properly with modern encryption standards in networks. 4G. Operators change them for free in the salons, and this procedure often works wonders with the speed of the Internet on the Redmi Note and other models, and the case of the smartphone also matters. If you use a case with metal inserts or magnetic mounts, it can shield the signal. The antennas in modern Xiaomi phones are located around the perimeter of the case, and any overlapping of these zones leads to the loss of high-frequency signal. LTE, which is worse than the obstacles that 3G. Finally, the most common but important factor is the operator’s coverage. Even the most powerful flagship Xiaomi 14 Ultra will not give 4G, if the nearest tower is loaded or under repair, in such cases, forced LTE Only will result in a total loss of communication ("No network"). Use coverage maps or a neighbor survey to see if the problem is local to your ISP. ⚠️ Warning: Constant network search or transmitter power limit (when the signal is weak but you are holding it) 4G) significantly accelerates battery discharge and heating of the body. 💡If none of the software methods worked, the problem is likely to be physical. SIM-map or lack of operator coverage in your location.
Frequently Asked Questions (FAQ)
Is it safe to keep LTE Only on a regular basis?
Using LTE Only mode is safe for hardware smartphones, but uncomfortable for the user. You can miss important calls as the 2G/3G network for voice communication will be disabled. Use this mode only when you need stable Internet for work or games, and you expect calls through messengers.
Why are network settings reset after rebooting?
The engineering menu doesn't save LTE Only settings after the device is fully rebooted, which is a feature of Android implementation: you have to re-enter the code ##4636## and select the desired item every time you turn off the phone, and you can only automate this with root rights and special scripts.
Does changing region in phone settings affect 4G speeds?
Changing region in the Settings menu → Additional settings → Region (e.g. India or the United States) can unlock certain frequencies or change modem algorithms because different countries have different frequency standards. However, this does not guarantee speed gain and can cause excess system debris.
What to do if the 4G icon is missing after the MIUI update?
Once the firmware update is updated, APN settings are often disrupted. Go to your mobile network settings, select the access point, and click "Restore Default Settings." If it doesn't work, check if the traffic saving mode is activated, which may limit background data transfer.
Can custom firmware improve signal reception?
Castom firmware (Global ROM in China or vice versa) can have different modem drivers, sometimes flashing from the Chinese version to the global version solves frequency problems (Band 7 and Band 20), which can be disabled in the stock firmware for a specific region.