Xiaomi does not catch the network: diagnosis and troubleshooting

Xiaomi suddenly loses its signal or doesn’t see it at all SIM-The card can be taken by surprise at the most inopportune moment, and you look at the screen and you see a crossed-out SIM or a no signal icon, even though it was working just a minute ago. This behavior of the device is often associated not with a breakdown of the antenna, but with software failures or incorrect operator settings.

Most of the time, the problem is that MIUI or HyperOS software is in conflict with new communication standards, or that it's physically contaminated, and users don't panic and bring their phones to the service center, and there are a number of proven methods that can reconnect in-house in minutes.

In this article, we will go into detail the algorithms for different scenarios, from a simple restart of the communication module to complex manipulation of the engineering menu. It is important to understand that Android is a complex system where even a small failure in the configuration files can lead to loss of connection. Let's consistently rule out all possible causes.

Basic diagnostics and reboot of communication modules

The first thing to do when a network goes missing is to rule out a temporary software failure. Xiaomi’s operating system sometimes “forgets” to reconnect to the base station after leaving coverage or flight mode. A simple reboot of the device often solves the problem, since it completely clears RAM and restarts all system services, including the radio module.

If a normal reboot doesn't work, try force-switching the network modes, which forces the phone to re-register on the operator's network. SIM-Maps and mobile networks. You can find "Network type" or "Preferred network type" here».

Try temporarily switching the standard from 5G/LTE to 3G/2G, waiting for the network icon to appear, and then back to “4G/LTE (recommended).” This method often helps to “brake off” the suspended communication module that has stopped responding to the operator’s requests.

It’s also worth checking whether Do Not Disturb mode or special energy saving profiles are activated, which can aggressively limit background communication. In some HyperOS firmware, battery optimization can mistakenly “sleep” the system process responsible for registering on the network.

Problems with SIM-card-and-slot

Physical contact between SIM-And the cards and the phone are one of the most common causes of unstable signals, and over time, the contacts on the map itself can become oxidized, and the tray of a Xiaomi smartphone can accumulate dust. SIM-Cards" or constantly requires a pin code, the problem is most likely here.

⚠️ Attention: Remove the tray for SIM-cards only when the phone is turned off or using the standard retrieval function to avoid damaging the card file system or short-circuiting contacts.

Take it. SIM-If you see scratches, chips or a strong darkening of the golden surface, you should replace the card with the operator. Also try to gently wipe the chip with a soft dry cloth without pile. Do not use alcohol or water, as liquid can get into the slot.

Check if the card is installed correctly in the tray. In modern Xiaomi models such as the Redmi Note or the Mi series, the tray is combined. Make sure the card lies in the intended recess and does not hang. If the tray is deformed, it may not provide a tight pinch of contacts.

Another important point is the age of the SIM-If you are using the same SIM card more 5-7 In the past, its contacts may have worn out and its internal memory deteriorated, and operators recommend changing the cards periodically, as older samples may not work properly with modern encryption standards. 4G/5G.

APN settings and access points

Even if the phone sees the network and shows the signal level, the Internet may not work due to the wrong settings of the access point APN (Access Point Name), which is the "address" that the phone uses to access the operator's gateway to access the global network, and if you change the tariff or update the firmware, these settings can be confused.

To check or create a new access point, go along the way: Settings → SIM-maps and mobile networks → Choose. SIM-map → Access points (APN). Here you will see a list of available profiles. If the list is empty or the Internet is not working, click Reset (usually at the bottom of the screen or in the three-dot menu) to restore factory settings.

If automatic reset didn't work, create a hotspot manually. You'll need data from your carrier's official website. Usually you only need to enter Name and APN. The remaining fields (login, password, proxy) in modern 4G networks are often left blank.

After entering the data, be sure to click Save and select the profile you created by ticking. Without this step, the settings will not apply. After that, it is advisable to turn on the flight mode for 10 seconds and turn it off so that the phone again registers with the new parameters.

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If you don't have the Internet after you enter the APN settings, try selecting PAP or CHAP in the Authentication Type field, and only the word in the APN Type field: default. Sometimes extra parameters in the type list interfere with the connection.

Resetting network settings to factory

When simple methods don't work, you need to do a deeper reset, and it's important to understand that this operation doesn't delete your personal files, photos or apps. It only returns to factory values the parameters of Wi-Fi, Bluetooth and mobile data.

To perform the reset, go to Settings → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth. In some versions of MIUI, this item may be in the Advanced Settings or About Phone section (after repeatedly clicking on the kernel version, but this is rare).

After pressing the Reset button, the system will ask you to confirm the action by entering the unlock password, which will take a few seconds, and then the phone will restart, and you will have to re-enter the passwords from your Wi-Fi networks and reinvent your Bluetooth devices.

This method is especially effective if you recently upgraded from Android 13 to Android 14 or changed carrier.Old configuration files can conflict with new system libraries, causing permanent connection breaks.

Engineering menu and choice of preferred network

For advanced users who want to manually control a communication module, there is an engineering menu, where you can force a phone to use only a certain communication standard, such as only LTE, ignoring overloaded 2G/3G towers.

To enter the menu, dial ##4636## in the phonebook. The hidden Test menu will open. Select Phone Information. Here you will see the drop-down list of Set Preferred Network Type.

Recommended values for stable 4G:


LTE Only (LTE only) for forced 4G




LTE/TD-SCDMA/GSM - Standard Automatic Mode

⚠️ Attention: Selection of regime «LTE Only" can cause you to stop taking incoming calls if your carrier does not support VoLTE technology.Use this mode only for an internet speed test, and then return the standard settings.

In the same menu, you can see the real strength of the signal in dBm. a value closer to 0 (for example, -80 dBm) indicates a great signal, and values below -110 dBm indicate an extremely weak coverage, where the phone can constantly lose network regardless of settings.

Hardware malfunctions and communication module

If neither of the software methods worked, there is a high probability of hardware malfunction: Xiaomi and Redmi smartphones sometimes encounter a dump of the antenna module or damage to the plume connecting the lower board (where the charging connector and antennas are located) to the motherboard.

A common cause is a phone crash, and even if the screen is intact, the antenna connector may have moved away, and it's also worth checking if the speaker or the antenna strip is covered by a metal case, and the metal shields the signal, and the phone starts to frantically search for the network, quickly discharged.

In rare cases, the radio module itself on the motherboard fails, which can occur due to a voltage surge when using unoriginal charging or moisture, in which case only qualified repairs in the service center with replacement components will help.

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If the phone only loses network in certain places (basement, elevator, suburban area) - it is a problem of coverage of the operator, not a malfunction of the phone.