Where to put it SIM-map 4G In smartphones Xiaomi: a detailed guide

You just bought a new Xiaomi smartphone and want to connect mobile internet, but aren’t sure which slot to insert into SIM-map 4G? Or have you encountered the fact that once you install a card, the Internet does not work, although everything must be configured automatically? This problem is familiar to many users, especially owners of devices with hybrid slots, where one tray supports either a second or a second. SIM, microSD card.

In this article, we will understand how to choose the right slot for the main one. SIM-Internet maps, what settings to check in Xiaomi, and why 4G It doesn't work even if you're installed correctly, and you'll also learn how to determine the type of slot in your model and what to do if your smartphone doesn't see the network.

It does not matter if you have the flagship Xiaomi 14 Ultra or budget Redmi Note 12 – the principles of working with the company. SIM-The cards are the same for most of the brand's devices, and the key is to take your time and follow the step-by-step instructions.

Types of slots for SIM-maps in Xiaomi smartphones

Xiaomi smartphones are equipped with different types of trays for SIM-It depends on where and how you can install a map for the mobile Internet:

📱 Two separate slots (Dual) SIM) — Both support nano-SIM and you can use two cards at the same time (e.g. in Xiaomi). 13T Pro).
🔄 Hybrid Dual Slot (Hybrid Dual) SIM) — One tray for nano-SIM, the second - or the second SIM, MicroSD (commonly available in Redmi Note) 11/12, POCO X5).
📌 One slot + eSIM - Physical nano-SIM + Virtual eSIM (found in new flagships, for example, Xiaomi 14).

Usually the main slot (Slot) 1) always supportive 4G/5G, And here's the second one. 2) It can be limited, for example, in hybrid trays, the second one is SIM often only works in the mode 2G/3G, If it is installed instead of microSD.

To find out what type of slot in your smartphone, check:

📄 Official documentation on the Xiaomi website (enter the model in search).
🔍 Labeling on the tray – usually it says whether it supports microSD.
📱 Phone Settings: Go to Settings → The phone. → General information → Status SIM-map.

📊 What kind of Xiaomi smartphone do you have?

Redmi Note 12/13

POCO X5/X6

Xiaomi 13/14

Other

Where to put it SIM-map 4G: basic

If your smartphone supports two physical devices SIM-For mobile internet, always use Slot 1?

⚡ Network priority: Slot 1 It usually supports all ranges. 4G/5G, while Slot 2 may be limited 3G or 2G.
🔄 Automatic setup: Operators by default link the Internet to the first SIM-map.
📶 Communication stability: Second SIM Hybrid slots may lose network when microSD is actively used.

Exception: if your smartphone supports Dual 4G (For example, Xiaomi 12 Pro or POCO F4 GT), both SIM-Cards can work in networks 4G But even then, Slot 1 is still the preferred Internet option.

To check which slot is active for mobile data:

Open the Settings. → SIM-maps and mobile networks.
Select the mobile Internet option.
Make sure you're selected. SIM-Slot 1 card (if any).

Turn off your smartphone before removing the tray|

Use the metal key from the kit|

Make sure the nano-SIM is properly trimmed (no burrs)|

Check if there are any scratches or dirt on the contacts of the card-->

What to do if 4G not working after installation SIM-map

You put a card in Slot 1, but the Internet is still missing, and here are the most common reasons and solutions.

Problem.	Reason.	Decision
No badge. 4G/5G status-line	SIM-The card is not activated for the Internet	Call the operator or check the balance (possibly need a tariff with the Internet)
The Internet only works in 3G.	In the settings, the wrong type of network is selected	Go to Settings. → SIM-map → [yours SIM] → Network type and select 4G (preferably)
The symbol "!" next to the network indicator	No registration of the operator's network	Restart your phone or manually select the network in Settings → Mobile network → Network operators
The internet is there, but it is very slow.	Active energy saving mode or limited background traffic	Turn off traffic savings in settings SIM-maps or add applications to exceptions

If none of these options worked, try:

🔄 Reinstall SIM-Card (sometimes contacts are not well-suited).
📱 Reset network settings: Settings → System system → Resetting settings → Resetting Wi-Fi, Mobile Network and Bluetooth.
🔧 Update – sometimes network bugs are fixed in new versions MIUI.

⚠️ Note: If you use Xiaomi with a hybrid slot and insert a microSD instead of a second one SIM, Make sure the memory card is formatted as internal storage, otherwise it may conflict with the mobile network.

Features of settings 4G on popular Xiaomi models

Some Xiaomi smartphones have unique nuances when working with SIM-Let's look at the most common models:

Redmi Note 12/13 and POCO X5 (hybrid)

In these devices, Slot 2 supports only 2G, If you're not using a microSD, turn on 4G second SIM:

Make sure that Slot 1 has the basic SIM-map.
Go to Settings. → SIM-maps and mobile networks → [SIM 2] → Turn on 4G.
If the option is not available, your operator does not support the option. 4G second SIM in this region.

Xiaomi 13/14 (Dual 4G)

Flagships support 4G both SIM-maps, but by default the Internet is tied to Slot 1:

Open the Settings. → Mobile network → Access point (APN).
Choose. SIM-The card you want to activate the Internet for.
Make sure that APN Operator is configured correctly (usually the settings are loaded automatically).

POCO F4/F5 (slot-slots)

Both of them. SIM support 4G, but for stable work is recommended:

📶 Use Slot 1 for the main SIM internet-bound.
🔄 Disable Auto-Switching Network in Settings if there are communication breaks.

What is VoLTE and why is it important for you 4G?

VoLTE (Voice over LTE) — technology that allows you to call over the network 4G non-switch 3G/2G. If you have VoLTE on, the calls will be clearer, and the Internet will not shut down during the conversation: 1. Go to Settings. → SIM-maps and mobile networks → [yours SIM] → Enable VoLTE. 2. If the option is not available, check whether your operator supports it (in Russia VoLTE is available from MTS, Beeline, MegaFon, Television).2).

How to check if it works 4G yours SIM-map

Sometimes the problem is not in the smartphone, but in the SIM-This is how you diagnose a problem:

Check the network indicator: 📶 4G+, LTE or 5G — it's okay. 📶 3G, H+, E – the network operates in an outdated standard. 📶 No service or only emergency calls — SIM-card not registered online.
Measure Internet speed: Open your browser and go to speedtest.net. If the speed is below 5 Mbps, it may be a problem for the operator or in the coverage area.
Check it out. IMEI: Dial *#06# - if IMEI missing or incorrect, the smartphone may be blocked.

If the speed is low, the indicator shows 4G, try:

🔄 Switch to another network manually (Settings) → Mobile network → Network operators → Networking).
📡 Disable and re-enable Flight Mode (sometimes this resets the connection).
📞 Call the operator and check if your rate is limited by speed.

⚠️ Note: If you use Xiaomi with custom firmware (like LineageOS or Pixel Experience), problems with the 4G They may be associated with incorrect modems, and in this case, the flashing on the official modem will help. MIUI.

Frequent errors in installation SIM-maps in Xiaomi

Even experienced users sometimes make mistakes that lead to the lack of Internet access.

🔀 We confused the slots - inserted the main SIM in the second slot, where 4G unsupported.
📱 Do not turn off the phone before installing the card (hot replacement can cause a failure of registration in the network).
🔧 Not updated. APN After changing the operator (old settings may conflict).
📶 Use incompatible SIM (For example, a cropped micro-SIM instead of a nano-SIM).
🔄 No resets to the network after the update MIUI (Sometimes it leads to conflict).

To avoid problems:

Make sure that SIM-card activated by the operator|

Check if your tariff supports 4G/LTE|

Use only nano-SIM (no adapters)|

Turn off the phone before removing the tray|

Additional Tips for Stable Stability 4G Xiaomi

If you often experience communication interruptions or slow internet, try these tips:

📡 Turn off automatic network selection and select the operator manually (sometimes the automatic mode connects to congested towers).
🔋 Turn off the energy saving mode for SIM-maps: Settings → Battery → Energy conservation → Energy saving settings → Disable for mobile network.
📱 Update the modem firmware (in new versions) MIUI Often improves the networking experience).
🔄 Use the NetMonster app (available on Google Play) to monitor signal strength and select the best tower.

If you travel frequently, pay attention to your roaming settings:

Enable Data in roaming in the settings SIM-map.
Please check with the operator if it is supported. 4G host country.
Use locally. SIM-Savings cards (but check frequency compatibility).

💡

If you have Xiaomi with support 5G, But the network is not catching, try manually to enable ranges n78 (3.5 GHz) and n1 (2.1 GHz) in the engineering menu. To do this, dial ##4636##, select Phone Information and check the network settings.

FAQ: Frequent questions about SIM-map 4G Xiaomi

Can we use two? SIM-map 4G simultaneously?

Yes, but only if your model supports Dual. 4G (for example, Xiaomi 13/14, POCO F4 GT). In most budget devices (for example, Redmi Note) 12) second-second SIM only works 3G/2G, If the hybrid slot does not have a microSD installed.

What to do if your smartphone doesn’t see SIM-map?

Try the following: Reinstall SIM-check if there is any damage to the contacts of the card or tray. SIM-Soft cloth cards (sometimes oxidation interferes with communication), update your smartphone software or reset your network settings. If nothing helps, contact the service center (possibly an antenna module problem).

How to Transfer the Internet to One SIM-card?

Go to Settings. → SIM-maps and mobile networks → Mobile Internet and choose the right one SIM. If the option is not available, contact the operator and ask to reconfigure the Internet service to another card.

Why? 4G It only works in certain applications?

You probably have Traffic Saving Mode enabled or limited background access for individual applications. → Annexes → Application management → [select the application] → Mobile data. Settings → SIM-maps and mobile networks → Saving traffic.

Can I use eSIM for the Internet on Xiaomi?

Yes, if your model supports eSIM (e.g. Xiaomi) 13/14). To activate: Get an eSIM from the operator (usually via an app or office). → SIM-maps and mobile networks → Add eSIM. Scan it. QR-Once activated, the eSIM can be used for the Internet in the same way as a physical one. SIM.

💡

If your smartphone Xiaomi does not catch 4G, Check the slot first (Slot 1 is preferred), then the settings APN And the type of network, 90 percent of the time, the problem is solved without going to the service.