How to improve the quality of communication on Xiaomi Redmi 9: from weak signal to stable connection

Why Redmi 9 is Bad at Catching Networks and How to Fix It

Weak mobile signal, call interruptions or slow internet on Xiaomi Redmi 9 are common problems that can occur due to software failures and hardware reasons. Unlike flagship models, budget smartphones often save on antenna modules, making them more vulnerable to interference, but in 80% of cases, the situation can be fixed without going to the service center.

In this article, we will look at all possible causes of poor communication, from an incorrect operator to physical antenna damage, and give step-by-step instructions for setting up Redmi 9 for the most stable signal. MIUI, Xiaomi does not advertise, but which can radically improve the reception of the network.

If your smartphone suddenly stopped catching the network after updating or falling, first check the basic parameters. If the problem has been observed since the purchase, it may be due to a defect in the antenna module or incorrect firmware.

1. Check the basic network settings

Before digging deeper, make sure Redmi 9 includes all the necessary settings for stable connectivity, often users accidentally disable key options or choose sub-optimal modes.

Open the Settings. → SIM-Maps and mobile networks and check:

• 📶 Network mode: must be installed 4G/3G/2G (If only selected 4G, In areas of low coverage, the phone will not switch to 3G, Which will cause a communication breakdown.
• 🔄 Automatic network selection: option must be activated.Manually selected network may perform worse if you move frequently.
• 📡 Roaming: If you are in a border area, turn on roaming to automatically connect to the nearest tower.

You should also go to Settings → Additional → Mobile Network and check:

• 🔗 Access point (APN): If the parameters are reset, the communication will be unstable.
• 📱 Double. SIM: If you use two cards, one of them can block the other. SIM.

If the connection hasn't improved after this manipulation, move on to the next step. Importantly, some settings may differ depending on the version of MIUI. For example, in MIUI 12, the path to APN looks different than in MIUI 14.

2. Update firmware and reset network settings

Often, communication problems on Xiaomi Redmi 9 arise from outdated software or conflicts in network configurations. The manufacturer regularly releases patches that fix the communication module errors, so the first thing to do is update the firmware.

How to update MIUI:

1. Go to Settings → About the phone → System update.
2. Click Check Updates and wait for the search to be completed.
3. If a new version is available, download it and install it. Don't interrupt it! It could cause the communication module to crash.

If the update does not help, reset the network settings:

1. Open the Settings. → Memory and SIM-map → Resetting settings.
2. Select Reset Wi-Fi, Mobile Network and Bluetooth settings.
3. Confirm the action and restart the phone.

Make sure that passwords from Wi-Fi are saved

Remember your APN settings (or take a picture)

Disable important notifications during the reboot

Check the balance SIM-Cards (sometimes resetting requires) SMS-confirmation)-->

Once reset, the phone will automatically select the optimal settings for your operator, and if the problem persists, it may be due to hardware malfunctions or incorrect settings on the operator side.

⚠️ Warning: Resetting network settings will remove all stored Wi-Fi networks and Bluetooth passwords. VPN or APN, They'll have to re-configure.

3. Signal reception optimization: hidden MIUI settings

Xiaomi hides a number of useful options that can significantly improve communication quality, which are not available through the standard interface, but can be activated using an engineering menu or special codes.

The most effective way is to enable 4G Forced Mode (if your carrier supports it).

1. Open the phone app and enter the combination: ##4636##
2. In the menu that opens, select Phone Information.
3. Scroll down to the Set your preferred network type.
4. Select LTE only (4G only). If this mode is unstable, try LTE/WCDMA.

Another useful trick is to turn off the automatic 2G switch, which often occurs in low signal areas and degrades Internet speed.

• Enter the phone keyboard: ##2263##
• Select Band Selection (Frequency Selection).
• Only mark the ranges that your operator supports (check them on the official website).

These settings can increase communication stability by 15 to 30 percent, especially in urban environments where the signal is often screened by buildings, but beware: incorrect settings can make things worse.

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If after changes in the engineering menu, the connection is completely lost, reset the network settings (see section 2) or restart the phone in safe mode (press the power button → “Safe mode”).

4.Verification SIM-card-slot

Often the cause of poor communication lies not in the phone, but in the damaged one. SIM-Redmi 9 is particularly sensitive to contact quality, so even microscopic dust or oxidation can cause signal breaks.

How to diagnose the problem:

• 🔍 Visual inspection: get out SIM-Check the card for scratches, chips or darkening of contacts, and check the slot for debris.
• 🔄 Test on another phone: insert SIM-If the problem persists, it is the operator's fault or the card itself.
• 🛠️ Cleaning contacts: clean your contacts carefully SIM-cards and slots with an alcohol napkin!

If SIM-The map is fine, but the connection is still unstable, try it:

• Move the card to another slot (if you use Dual SIM).
• Turn off the second. SIM-The card (if any) – sometimes they are in conflict.
• Replace SIM-New card (especially if it is older than 3-5 years) Modern nano-SIM is less prone to wear and tear.

⚠️ Note: If after cleaning the slot or replacing SIM-The card card phone stopped seeing the network at all, check if the contacts in the slot are bent. This is a common problem after sloppy installation of the card.

5. Hardware causes of poor communication and their elimination

If software methods don’t help, the problem may lie in the hardware of the Redmi 9. Xiaomi budget models often suffer from:

• 📡 Poor quality of the antenna module (especially in the 2020-2021 batches).
• 🔌 Oxidation or breakage of the antenna plume (often after falls or moisture intrusion).
• 🛡️ Screening the signal with a metal case (if you use a case with metal elements).

How to diagnose a hardware malfunction:

1. Safe Mode Test: Reboot your phone with the power button pressed and select Safe Mode. If the connection improves, it's the software's fault, if not the hardware's fault.
2. Check without a case: remove the case and check the signal quality. Metal or magnetic accessories can block the antenna.
3. Diagnostics through the engineering menu: type ##4636##, select Phone Information, and look at Signal strength. If it's consistently below -100 dBm, there's likely to be an antenna problem.

If you suspect a hardware malfunction but don’t want to carry your phone to the service, you can try a temporary solution:

• Use an external antenna (connected via a OTG-Adapter suitable for stationary use.
• Attach a metal plate to the back cover (for example, from an old hard drive) – this can improve reception by reflecting the signal.
• Change the location of the phone: for example, on the windowsill or closer to the window, the signal is usually better.

Hardware repair of the antenna will cost 1000-3000 ₽ If the phone is warranty, contact the official Xiaomi service - in this case, the repair can be free of charge.

6. Alternative ways to improve communication

If standard methods have failed, try non-trivial solutions that often help in difficult cases:

Use of applications to amplify the signal:

• 📱 Network Signal Speed Booster (optimizes network settings).
• 🔍 OpenSignal (shows the coverage map and helps you find the best place to receive).
• 🛠️ MTK Engineering Mode (for fine-tuning the communication module on MediaTek processors).

Roaming and frequency settings manually:

• If you travel abroad frequently, turn on Settings → SIM-map → Data roaming.
• In the engineering menu (#36446337##) you can manually select the frequencies that your operator catches best.

Use of Wi-Fi Calling:

If the mobile network is weak but there is stable Wi-Fi, activate Settings → SIM-map → This will allow you to call and use the Internet even in the absence of a cellular signal.The service is supported by most Russian operators (MTS, MegaFon, Beeline).

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Wi-Fi Calling is the only way to keep communication in basements, elevators or outside the city where there is no cellular network, but there is access to the Internet.

If neither method worked, consider buying a signal repeater (a repeater).The device costs from 3,000. ₽ It's a signal booster that's 50 to 100 meters away, and that's true for country houses or offices with poor surfaces.

FAQ: Frequent questions about communication on Xiaomi Redmi 9