Xiaomi Redmi 8 doesn't see SIM-What to do if your phone does not catch the network

Xiaomi Redmi 8 suddenly stopped recognizing SIM-The screen says "No net," "Put in." SIM-Don't panic - 80% of the time, you can solve the problem yourself without the help of a service center. This problem is typical for budget Xiaomi smartphones, especially after updates. MIUI or mechanical effects (falls, ingress of moisture).

In this article, we will look at all possible causes, from common contact contamination to hardware malfunctions of the communication module, you will receive step-by-step instructions with illustrations (for key steps), a compatibility table. SIM-Redmi 8 cards, and answers to frequent questions, and we will focus on the unique features of this model, such as the problem with the Redmi 8. IMEI post-reset.

Before you start the repair, check whether it works. SIM-If so, a problem with your smartphone. If not, ask the operator to change your card. Also make sure you don't have On-Plane Mode activated. → Connections and sharing → Flight mode).

1. Reset and hot discharge

Start with the simplest one, forced reboot, which works 30 percent of the time, especially if the crash is caused by a temporary software conflict. Redmi 8 has two ways:

• 🔄 Soft reboot: Press the power button for 10 seconds, wait for the menu to appear and select Reboot".
• ⚡ "Hot "reset": clamping down on the power + Volume up for 15 to 20 seconds until the phone vibrates and reboots.

If after the reboot SIM-The card is undetectable, try to re-extract it and repaint it. Do it with the phone turned off! Use the clip from the kit to open the tray. Pay attention to the position of the card - Redmi 8 supports Nano-SIM (3FF) In the first slot and Nano-SIM + MicroSD in the second. Installation may damage contacts.

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If SIM-The card hangs in the slot, put a thin layer of insulation under it (not sticky to the contacts.

Once removed, look at the contacts on the map and on the phone — they should be clean, without oxidation. If you notice a green coating, gently clean it with a blower or alcohol. Do not use metal objects — this can damage the gilded coating.

2. Check network settings and SIM mode

Sometimes the problem is the wrong network settings. Go to Settings. → SIM-Maps and mobile networks and check:

• 📶 Network mode: must be selected 4G/3G/2G (If only the car was worth it. 4G, The phone will not be able to connect to 2G/3G low-cover.
• 🔄 Automatic network selection: turn on this option if it is disabled. Manually selected network can "fly" after the update.
• 📱 Priority SIM-Cards: If you have two cards, make sure the main card is chosen for calls and mobile internet.

Pay special attention to the item "Access Point (APN)" If the settings are lost, the phone will not be able to connect to the Internet, even if there is a network signal. Click Add APN and enter your operator's data (you can find them on the official website).

After saving the settings, restart your phone. If the changes don't apply, reset your network settings: Settings → System → Resetting → Network reset.

3. MIUI Update and reset to factory settings

If the problem has occurred after a firmware update, a bug in MIUI may be to blame. Redmi 8 is especially sensitive to updates due to the old Qualcomm Snapdragon 439 chipset. Check out the MIUI version in Settings → About Phone. Current at 2026 is MIUI 14 (Android 10).

Solutions:

1. Remove the update (if the problem has recently appeared): go to Settings → About Phone → System Update, click on the three dots in the upper right corner and select "Delete the downloaded update." After the restart, the phone will return to the previous version.
2. Update MIUI manually: download the full firmware package for Redmi 8 (codenamed olive) from Xiaomi’s official website and install via Settings → About Phone → System Update → Three Dots → Select a firmware file.

Make sure the battery is over 50 times charged%|

Backup the data (photos, contacts, SMS) |

Remember the username/password from your Mi Account (linked to your phone)|

Extract. SIM-card and memory card (if any)

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If the update didn't work, reset to factory settings. This is a radical method, but it often resolves software conflicts. Importantly, after a reset, Redmi 8 may lose its IMEI. To avoid this, write down your current IMEIs before reset:

1. Please enter the phone keyboard *#06#.
2. Write down both numbers (if you have two). SIM-map).
3. Take a screenshot or write them down on paper.

To reset, go to Settings → About Phone → Settings Reset → Erase all data. Once the reboot is done, the phone will prompt you to restore data from the backup — select Skip to avoid carrying old errors.

4. Checking hardware faults

If the software methods didn't help, the problem could be a physical breakdown.Redmi 8 has several vulnerabilities:

• 🔌 Tray SIM-Cards: plastic locks often break, so the card is not pressed against the contacts.
• 📡 Antenna module: after falling, the plume may move away or the soldered contact on the motherboard may crack.
• 💧 Contact oxidation: If the phone was exposed to rain or high humidity, the contacts could oxidize.

For diagnosis:

1. Call the tray with a multimeter: if there is no resistance between the tray and motherboard contacts, the problem is the chain break.
2. Check the antenna plume, which is located under the back cover, next to the main camera, and if the plume has moved, gently plug it back in.
3. Check the board: it should not be black spots (a sign of a short circuit) or cracks.

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If you do not have experience in electronic repair, do not disassemble the phone yourself. Contact the service center - the cost of diagnosis usually does not exceed 500-1000 rubles.

Typical malfunction of Redmi 8 - the chip dump of the power module of the communication module (UFI or RF-It's because of overheating or mechanical shock:

• The phone doesn't see any of them. SIM-map, but Wi-Fi is working.
• The engineering menu (#4636##) displays a Radio off error.
• After rebooting for a split second, the network signal appears, then disappears.

Repair of such a breakdown requires soldering of the chip on specialized equipment (infrared station), the cost of repairs is from 2000 to 5000 rubles depending on the region.

⚠️ Warning: If you see corrosion on the board (green or white), don't turn on your phone! This can short circuit and cause other components to fail.

5. IMEI recovery and communication module firmware

One of the most common reasons Redmi 8 is not running a network is because of the loss of IMEI, which can happen after:

• Misupgrade MIUI update.
• Reset to factory settings.
• Installations custom firmware (for example, LineageOS).

Check the IMEI by dialing *#06#. If zeros or "Invalid IMEI" are displayed instead of numbers, follow the instructions:

Download the archive with utilities (QPST + Qualcomm drivers)|

Install drivers for Snapdragon 439|

Connect your phone in EDL mode (clamp Volume up + Volume down + Power)|

Run QPST Configuration and select the phone port |

In Software Download, download a firmware file with the correct IMEI

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For Redmi 8, the firmware from Xiaomi’s official website (Global Stable version) is suitable. Importantly, do not use firmware for other regions (for example, China), this can block the network.

If you are not sure of your abilities, use an alternative method - recovery through the engineering menu:

1. Install the MTK Engineering Mode app (yes, it works on Snapdragon!).
2. Go to Engineer Mode → Connectivity → CDS Information → Radio Information → Phone 1.
3. In the field AT+ command: AT +EGMR=1,7,"IMEI_1" AT +EGMR=1,10,"IMEI_2" (substitute IMEI_1 and IMEI_2 on your numbers).
4. Reboot the phone.

⚠️ Attention: change IMEI It can be illegal in some countries. In Russia, it is only allowed to restore the original number. IMEI!

6. Alternative methods: firmware rollback and custom solutions

If standard methods don’t work, try rolling back the firmware to an older version of MIUI. Some users note that after upgrading to MIUI 12.5 or MIUI 13, Redmi 8 loses its network, and the solution is to return to MIUI 11 or MIUI 12.

For this:

1. Download the archive with the desired firmware version (for example, olive_global_images_V11.0.8.0.PCNMIXM).
2. Rename the file to update.zip and place it in the root of the phone’s memory.
3. Go to Settings → About Phone → System Update → Three Dots → Select a firmware file.
4. Confirm the installation and wait for completion (10-15 minutes).

If the official firmware does not help, you can try custom firmware, such as Pixel Experience or Havoc-OS.

• 🔓 You will need to unlock the bootloader (bootloader).
• 📉 Possible problems with the camera or sensors.
• ⚠️ The guarantee will be lost.

Instructions for unlocking the bootloader for Redmi 8:

1. Link your Mi Account to your phone in Settings → Mi Account.
2. Go to the Mi Unlock website and download the utility.
3. Start the phone in Fastboot mode (clamp Power + Volume down).
4. Connect to the PC and follow the instructions in the program.

Once unlocked, custom firmware can be installed via TWRP, but we recommend this method only to advanced users.

7. When there's only a service center left

If none of these methods worked, the problem is probably hardware, and here are some signs that you should check with the service:

• 🔧 The phone doesn't see any of them. SIM-Cards (including knowingly working).
• 📉 The signal level of the network always shows 0 dBm or No maintenance.
• 🔥 On the board, traces of burns, swollen capacitors or cracks are visible.
• 💦 The phone fell into the water or was subjected to a strong vibration (for example, in a car).

Cost of repair in the service center:

Before the service visit:

• Make a backup copy of the data (if the phone is still turned on).
• Untie your Mi Account if it is tied.
• Check if the service has original parts for Redmi 8.

⚠️ Warning: Avoid garage shops that offer repairs for 500 rubles. Often they use used parts or Chinese replicas that fail after 1-2 months.

FAQ: Frequent questions about problems with SIM-map 8