How to Enable Communication on Xiaomi: A Step-by-Step Guide

Users of smartphones Xiaomi, Redmi and Poco often face a situation when after buying a new device or resetting the settings, the gadget ceases to see the cellular network. SIM-A card or a "No Network" sign can happen for a variety of reasons, from the banal lack of activation of the slot in the system to deeper software failures in the firmware. MIUI or hyperos.

It is important to understand that enabling communication is not just a physical installation of the operator’s chip; modern smartphones require the correct software configuration, especially if the device was brought from China (Global Version) or has two active devices. SIM-Incorrect network priority settings can cause the phone to "cling" to a weak one. 2G, ignore 4G or 5G.

In this article, we will take a detailed look at all the steps of activating mobile communications, configuring access points and eliminating common errors, learn how to manage slots, switch communication standards and diagnose problems with the radio module without going to the service center.

Primary activation SIM-map

The first step after physically putting the card into the tray should always be software activation. Unlike older push-button phones, modern Android smartphones may not start the communication module automatically if the settings are prohibited or if the system is stuck in flight mode. Go to Settings. → SIM-maps and mobile networks.

In the menu that opens, you'll see a list of cards installed. If the slot is active but not connected, check the "Use" (or "Enable") switch. It should be blue. Sometimes the system suggests you choose a use case for each card: calls, the Internet or both. A logical error here is common: the user chooses "Only the Internet" for the main card, and then wonders why incoming calls don't pass.

Note the status of the card. If the system writes "Unknown" or "No Service" immediately after turning on, try restarting the device. In rare cases, manual switching between slots is required to "wake up" the SIM power controller.

⚠️ Warning: If after switching on the phone starts to heat up strongly in the lower part of the case, immediately remove SIM-This may indicate a short circuit in the contacts of the card or a malfunction of the communication module itself.

Prioritizing Networks and Communication Standards

The correct operation of the Internet and voice communication depends on the type of network chosen. SIM-map → The preferred network type is recommended to choose a combined mode, for example, Preference 4G (LTE). Compulsory inclusion only 5G This can cause loss of signal in areas of unreliable reception, as the phone will no longer see stable towers. 4G.

For users who travel frequently or live at the edge of coverage, the question of operator choice is relevant. In the Network Selection section, the default mode is Auto. If the phone can not find the network for a long time, try to switch to manually. The device will scan the air and give a list of available operators. Choose your provider from the list.

It is worth noting that some Chinese versions of Xiaomi smartphones may not support all frequencies of Russian or European operators (for example, Band 7 or Band 20 are absent), this is not a software bug, but a hardware limitation. You can check the supported frequencies in the engineering menu or through special applications like Network Cell Info.

Conflicts between the two SIM-maps and slot management

Xiaomi’s dual-sim smartphones have a single radio module that (shares time) between the two cards.This means that while one card is busy talking, the second card may be unavailable or go on standby.

In the control menu SIM-You can use cards to determine which one is going to be used for the mobile Internet, which is usually a map with a lot of traffic. SIM Or leave the choice "Always ask." The latter option is convenient if you use different rates for different purposes, but it requires extra action on each dial.

If you notice that when you talk actively on one card, the second card loses its network completely (“Unavailable”), this is the normal behavior of the DSDS (Dual SIM Dual Standby) technology, and this can only be solved by enabling the VoLTE function, if it is supported by your operator and tariff.

Configuring APN access points for mobile Internet

Even if the indicator 4G Internet may not work due to incorrect settings of the access point APN. They are usually automatically loaded when installed. SIM, But if you crash or you manually flash them, you have to re-enter them. → SIM-maps and mobile networks → (Choose. SIM) → Access points (APN).

In the list you open, you need to create a new point or edit an existing one. Data to fill out (name, APN, login, password) must be taken on the official website of your operator. An incorrect symbol in the APN field (for example, an extra space) will lead to no data transfer.

Example of APN settings for the operator (conditionally):


Name: MyOperator Internet




APN: internet.myoperator.ru




Type of authentication: PAP or CHAP




Type APN: default,supl

After entering all the parameters, be sure to click the Save button (often hidden in the three-dot menu or the button at the bottom of the screen) and select the created point by ticking or an active circle next to it. Without this step, the settings will not apply.

⚠️ Warning: When creating a new access point, do not copy the settings from third-party sources blindly. APN No extra spaces at the beginning or end of the line – the system reads them as an error.

Solving problems with IMEI and communication module

The most alarming symptom is when the settings indicate IMEI: null or unknown, and the status bar is lit by a cross, which indicates a loss of communication between the processor and the modem, often after a failed update, reset partitions or use of informal firmware.

The first thing you need to do is check the IMEI in the engineering menu. Type *#06# in the ringer. If the number doesn't match or doesn't match the number on the box/sticker under the SIM tray, the problem is serious. 90% of the time on the global versions, this is solved by flashing through the computer using the Mi Flash utility and completely clearing the memory.

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If the IMEI is gone after the update, don’t rush to bring the phone to the service. Try resetting the network settings: Settings → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth.

For Chinese versions that have been globally flashed, the loss of IMEI is a frequent occurrence due to regional certificate conflicts, in which case only a return to stock Chinese firmware, restoration of IMEI (which requires root rights and special tools), and subsequent reflashing to a global version with an unlocked bootloader help.

Diagnostics through the engineering menu and resetting settings

If simple methods don't work, you should turn to hidden diagnostic tools, enter the code ##4636## in the phone app, and the Check menu will open, where you can select Phone Information, and you can force the radio mode to switch.

In the "Install preferred network type" field, select LTE Only (4G only) or NR/LTE/GSM. If the signal and the Internet appear after that, then the module is good, but the system cannot correctly reconcile the standards with the tower. Return the setting to its original state after checking.

The last software method is to completely reset the settings to the factory. Before that, make sure to back up the contacts and photos. If after resetting and clean installation of updates, the connection does not appear, there is likely a hardware malfunction of the antenna module or plume.

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If resetting and flashing did not return the IMEI and network, the problem lies in the “hardware”: the antenna plume, communication module or motherboard require repair in the service.