Xiaomi phone doesn't see SIM-Why this happens and how to get the network back in 10 minutes

You put it in. SIM-Xiaomi card, but phone refuses to "see" it? on screen, the words "No network" are on», «SIM-Card not found" or "Put in SIM», This problem is familiar to millions of users, from owners of budget Redmi Note to flagship Xiaomi 14. 80% of cases, the malfunction is solved independently without contacting the service center.

The reasons for the failure may be as in software errors (for example, after the update). MIUI), It's also a problem with hardware, from a contaminated slot to a damaged board, and in this article, we'll look at all the scenarios that we can think of, including the rare cases where the phone doesn't see just one of the two. SIM-You'll get checklists for diagnostics, step-by-step instructions for photos, and tips on how to avoid repeated failures.

Basic checks: what to do first

Before you take your phone apart or reset your settings, make sure that the problem isn't in the little things. Start with these steps -- they take no more than 5 minutes, but solve the problem 30 percent of the time.

• 🔄 Reset the phone. Press the power button 10 seconds before the turn off menu appears. Sometimes a failure in the communication module is fixed by a simple reboot.
• 📶 Check the coverage area, maybe the problem isn't with the phone, it's with the operator, like, you know, there's some technical work going on. SIM elsewhere.
• 🔍 Look at this. SIM-It should be free of scratches, chips or oxidation (green coating). If the contacts are dimmed, wipe them gently with a swallow.
• 📱 Try another one. SIM. Insert a card from another operator or test SIM (If the phone sees it, the problem is in your main card.

Pay special attention to the type SIM-Modern Xiaomi (e.g. Redmi Note 12 or X-ray) POCO X5) Only nano-SIM support. If you inserted a micro-SIM through an adapter, the contacts may not match. Also check if the card is inserted upside down - the tray usually has a diagram of the correct position.

2. Software failures: how to fix without disassembling the phone

If the basic checks didn't work, the software was most likely to be to blame, most often the problem occurs after:

• 📲 Updates MIUI (especially in beta versions).
• 🔧 Installation of custom firmware or root rights.
• 🛠️ Resetting settings to factory.

Here’s what you can do without losing data:

1. Reset network settings. Go to Settings → SIM-maps and mobile networks → Reset network settings, which will delete stored Wi-Fi networks and mobile Internet settings, but will not affect photos or apps.
2. Turn on/off flight mode. Activate flight mode for 30 seconds, then turn off. This force restarts the communications module.
3. Manual network selection. In the Settings menu → SIM-maps and mobile networks → Select the network to disable automatic search and select the operator manually.

If your phone stopped seeing SIM after the MIUI update, try rolling back to the previous firmware version.

1. Download the desired version of MIUI from the official Xiaomi website (choose stable, not developer).
2. Rename the file to update.zip and place it in the root folder of the phone.
3. Press Volume Up + Power to log in to Recovery, and select Install update.zip.

3. Hardware malfunctions: when the slot or board is to blame

If the software methods didn't work, the problem is probably physical damage, and here are the most common hardware causes:

To check the slot yourself:

1. Turn off the phone and remove the SIM tray using a paper clip (the hole is usually to the right of the slot).
2. Examine the contacts inside the phone – they should be clean, without green plaque (oxidation) or bent “legs”.
3. Wipe the contacts with isopropyl alcohol (at least 90%) and a soft brush. Don't use cotton cotton or paper - they leave a pile.

⚠️ Warning: If the phone has fallen into water or been exposed to extreme humidity, do not turn it on immediately after cleaning.Let it dry for at least 24 hours in a dry place (such as with silica gel!

4. Problems with two SIM-Why one works and the other doesn’t.

Many Xiaomi models (e.g. Redmi 10 or Xiaomi) POCO M4 Pros support two SIM-maps, but sometimes one of them is not defined:

• 📱 Incompatibility of standards. One slot can only support 4G, second — 2G/3G. Check in Settings → SIM-Maps and mobile networks, which standard is assigned to each card.
• 🔌 Damage to one of the slots, the second slot suffers more often (SIM2), It is used less frequently and can be oxidized.
• 📡 Operator conflict. Some combinations SIM (for example, MTS + Tele2 can block the work of one of the cards due to firmware errors.

To diagnose the problem:

1. Change it. SIM-If the second card earned in the first slot and the first one didn't, it's the slot.
2. Check the network priority settings. → SIM-Maps and mobile networks select for problem SIM regimen 4G (if maintained).
3. Turn off one of the SIMs for 1-2 minutes, then turn it back on, and sometimes this resets the communication module conflict.

If the phone sees both SIMs but doesn't catch the network, try manually prescribing APN settings.

1. Go to Settings. → SIM-maps and mobile networks → Access point (APN).
2. Click Add APN and enter your operator’s settings (they can be found on the official website, for example, for Beeline it is Internet.beeline.ru).
3. Save the settings and restart the phone.

5.Reset to factory settings: when it really helps

If all previous methods failed, the last software method is a hard reset, which will delete all data from the phone, so first:

• 📲 Make a backup copy through Settings → The phone. → Backup or Mi Cloud Backup.
• 🔐 Remember the Xiaomi account details (email and password) – after reset, authorization will be required.
• 📱 Remove the memory card (if any) to avoid losing files on it.

Resetting instructions:

1. Go to Settings → About the phone → Reset settings.
2. Choose to erase all data and confirm the action.
3. After the reboot, set the phone up as new and check the SIM.

⚠️ Note: On some models (Redmi 9, POCO X3) After reset, you may need to unlock the bootloader if you've previously blocked it. Without that, the phone won't turn on! Make sure you have access to the Mi Account tied to the device.

If the reset didn't work, the problem is guaranteed to be hardware.

• Contact the official Xiaomi service (if the phone is warranty).
• Check the cost of repairs in local workshops - replacing the slot SIM It'll cost 800 to 2000. ₽, a repair fee from 3000 ₽.

6. Rare cases: when the operator or firmware is to blame

Sometimes the problem isn't the phone, it's the external factors.

• 📡 Lockdown IMEI If the phone is bought from hand or brought from abroad, the operator can block it. IMEI For non-payment (e.g. in case of theft) IMEI IMEI.info.
• 🔄 The operator's database is broken. SIM-The card is active, but the operator does not see it on the network. Call support (for example, MTS: *111#, Beeline: *110#) and ask for re-registration of the card.
• 📱 Custom firmware conflict: If you've installed unofficial software (like LineageOS), the communication module may not work properly. MIUI.

The problem may also be regional limitations: Some Xiaomi models (especially the Global Version) block certain frequency bands. For example, the Redmi Note 11 for Europe does not support Russian Band 20 frequencies (800 MHz), which may prevent it from catching the network in remote regions.

💡

If the phone stopped seeing SIM after firmware, try Recovery to select Wipe → Wipe Modem (if any) and this will reset the communication module settings without losing data.

7.Prevention: How to Avoid SIM Problems in the Future

To avoid SIM recognition errors, follow these rules:

• 🛡️ Use a moisture-protected cover if you are outdoors often in the rain.
• 🔋 Don't take it out. SIM-card with the phone on – this can damage contacts.
• 📱 Update. MIUI Only through official channels (in Settings) → Updating the system).
• 🔄 Clean the slot once every six months. SIM from dust with compressed air (canister).

If you travel frequently, make it a rule:

• Before traveling, check the frequency support of your phone in the destination country.
• Bring a spare with you. SIM-Card or eSIM (if the phone supports the phone).

💡

The most common cause of malfunction SIM-The slot is the oxidation of the contacts due to moisture. Even if the phone did not sink, the condensation from temperature changes can cause corrosion.

Frequently asked questions