When Xiaomi’s favorite smartphone suddenly loses touch, it can be taken by surprise at the most inopportune moment.The device screen treacherously shows a crossed-out SIM card or the words “No network”, leaving you disconnected from the world. Most often the problem lies in a software failure or a weak contact, but sometimes the culprit is the communication module itself.
Before you bring your gadget to the service center, you should try to diagnose the malfunction yourself. In most cases, it takes only a few minutes to recover and requires no special tools. We will analyze all possible scenarios, from the banal dust in the slot to serious conflicts of the MIUI firmware.
Ignoring the problem can lead to a complete lack of communication, which makes the smartphone useless for calls and mobile Internet. The right sequence of actions will help to avoid unnecessary waste of time. POCO no longer define the operator.
Physical injuries and contact problems
The most common reason Xiaomi doesn't see a SIM card is because of the banal disruption of physical contact: The SIM card tray is a mechanical element that is prone to wear, contamination and oxidation. Even a microscopic speck of dust or fatty fingerprint from the fingers can interrupt the connection between the chip and the phone's contacts.
Frequently removing the tray weakens the spring contacts inside the slot. If the SIM card dangles or fits loosely, the device will not be able to read the operator's data, and you should also pay attention to the state of the chip itself: scratches on golden contacts or chips on plastic often cause a failure.
⚠️ Warning: Do not use metal objects (needles, pins) to clean the contacts inside the slot if you are not sure of your actions.This can lead to short circuit and combustion of the power controller.
To fix the problem, you need to remove the tray and inspect it carefully. Wipe the SIM card contacts with soft lilac-free fabric. If you have isopropyl alcohol, you can carefully process the chip, allowing it to dry completely before installation.
- 🔍 Visually check the trays for dents or deformities.
- 💨 Gently bleed through the SIM card slot with compressed air or a rubber pear.
- 🔄 Try flipping the SIM card (only if the tray is two-sided and the design allows you to do so).
- ✂️ Make sure the SIM card is trimmed to standard and doesn't get stuck in the tray.
☑️ Diagnostics of physical contact
System failures and MIUI errors
The MIUI shell, like any complex operating system, is not immune to errors. Sometimes the communication module freezes at the software level, stopping polling the SIM card slot, this can happen after a system update, installing a new application, or simply as a result of a long time without rebooting.
In such cases, the phone is technically functional, but the software interface of the radio module does not respond to the system's requests. The user sees the status of "Emergency Calls Only" or constant network search. Rebooting the device solves the problem in 80% of cases, since it completely reprograms the Initializes modem drivers.
If a simple reboot didn’t work, try a deeper network reset, which will return all network settings to factory values by removing stored APN access points and Bluetooth passwords, but often effectively treats software glitches.
How to Reset Network Settings on Xiaomi
It is important to note that once you reset your settings, you will have to re-enter your Wi-Fi passwords, but this step is critical to diagnosing a SIM card problem.
Software version conflicts and system updates
Often, when a phone doesn't see a SIM, it happens right after a firmware update. Developers may make a mistake in a new MIUI bill that affects how a RF module works, especially on betas or global firmware that hasn't been properly tested for a specific region.
If the problem occurred after the update, it is worth checking for a newer version of the software, in which the bug could already be fixed. If there are no updates, sometimes waiting for a stable version or a rollback to the previous firmware helps, although the latter requires skills and an unlocked bootloader.
Smartphones designed for the Chinese market (CN Version) may not work correctly with the frequencies or communication standards of some Russian or European operators without the correct flashing on Global ROM.
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Always back up your important data before installing an update, and in the event of a critical software failure, this will quickly restore the device to work without losing contacts and photos.
Check if the phone is on flight mode by accident, sometimes after updating the settings may get lost, and the phone remains isolated from the network.
Problems with the very SIM-map-and-operator
The possibility that the operator's plastic card itself is faulty is not ruled out, SIM cards have limited lifespan and can fail over time, and microcracks, contact oxidation, or the end of the chip's life cause the phone to fail to recognize it.
In addition, the operator may have had some technical work on the base station side, in which case the phone is good, the SIM card is intact, but the network is simply not available, and you can check the status of the network on the operator's website or by calling support from another number.
The most reliable way to diagnose is to exclude: Take out your SIM card and paste it into another phone. If it doesn't work there, then the problem is exactly in the card or the tariff. Conversely, insert the other carrier's knowingly working SIM card into your Xiaomi.
- 📞 Call the operator to check the status of the number and locks.
- 🔄 Insert the SIM card into another smartphone to check.
- 🏪 Visit the communication salon to replace the SIM card with a new one (often free of charge).
- 📱 Check if the number is not a ban on incoming / outgoing.
Network settings and operator selection
Xiaomi's smartphone settings have settings that directly affect network search. If you choose the wrong network type or mode of operation, the phone may ignore the SIM card. For example, if there is no 4G coverage in the region, and the settings are rigidly set only this standard, there will be no communication.
Also important is the operator selection option: you can select an automatic search menu or manually specify a specific provider, sometimes the automatic selection fails, and the phone clings to the weak network of a neighboring operator, ignoring your SIM card.
To fix this, go to the SIM card settings menu, where you can force a network type switch from 5G/LTE to 3G/2G to see if a signal appears, and if there is a connection on lower standards, then there is a problem with 4G/5G coverage in your zone.
| Parameter | Recommended value | Description of the impact |
|---|---|---|
| Type of network | LTE is preferred | It provides a balance of speed and coverage. |
| Choice of network | Automatically. | It allows the phone to find the best tower. |
| Data roaming | Off (at home) | It prevents unnecessary expenses abroad. |
| APN | Auto (by default) | Access points for mobile Internet. |
Hardware malfunctions of the communication module
If software methods and replacing the SIM card did not help, there is a high probability of hardware failure. In Redmi and POCO smartphones, the SIM card slot can move away from the motherboard after a fall or impact. Even a slight blow can disrupt the contact of the plume or the connector itself.
A more serious problem is that the radio or power controller fails, which often happens after moisture gets inside the case, and the water causes contacts to corrosion, and over time, the phone not only stops seeing the SIM card, but can also lose Wi-Fi or Bluetooth.
Diagnostics of the hardware requires disassembling the device and using a multimeter. It is not recommended to climb inside yourself if you do not have experience, as you can damage other components.
⚠️ Warning: If the phone falls into water, do not charge it or try to turn it on. This is guaranteed to short circuit and make repairs more difficult.
In some cases, it helps to warm up the phone (rebolling) if the contact under the chip has gone away, but this is a temporary measure.
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If the phone does not see the SIM card after falling or getting water, software methods are powerless - hardware repair is necessary in the service center.
Use of adapters and non-standard SIM cards
A common cause of instability is the use of adapters to turn a standard-sized SIM card into a micro or nano. Adapter plastic can be thicker than normal, causing the card to not fully enter the tray. Contacts do not close, and Xiaomi does not see the SIM card.
Also, homemade clippings of SIM cards with scissors can cause problems, if the cut line went too close to the chip or touched contacts, the card will work intermittently. It is better not to save and replace the card from the operator with a SIM card of the correct format.
Using adapters increases the risk of getting stuck inside the phone, and it can be very difficult to remove it without special tools, so if you use an adapter, try removing it and using a native-sized card.