Double. SIM-A map in Xiaomi smartphones is not just a convenience, but often a necessity: one for work, another for personal calls, or one for mobile Internet and another for voice. We put in a second SIM, and it doesn't detect, it doesn't catch a network, it conflicts with the first SIM. SIM-cards on Xiaomi, Redmi and POCO, including hidden settings and solutions to typical errors.
Slot configuration for SIM-Xiaomi cards may vary depending on the model. Some smartphones (such as the Xiaomi 13 Pro or Redmi Note 12) use a hybrid slot where the second slot is combined with a microSD card connector. SIM-maps and external memory, in other models, for example, POCO F5) Both slots are independent.Be sure to check the type of slot in the specifications of your device before you start setting up - this will save time and nerves.
If you just bought a Xiaomi smartphone or are trying to activate a second one for the first time SIM-This is a map, this guide will help you avoid common errors. We'll look not only at the basic steps, but also at the hidden functions. MIUI, which allows you to flexibly manage network priorities, switch between SIMs and even save battery power when using Dual SIM.
1. Compatibility Check: Does your Xiaomi support two? SIM-map?
Before trying to include the second SIM-Make sure your Xiaomi model supports the dual feature at all SIM (DSDS). Some budget or older devices may only have one physical slot, and the specifications indicate "Dual" SIM" The possibility of using eSIM (virtual) SIM-map).
How to check:
- 🔍 Look at the specifications of the model on the official Xiaomi website or in the store where you bought the smartphone. SIM (Nano-SIM, dual stand-by)".
- 📱 Look at the tray for SIM-If you have two separate slots under nano-SIM, you have two physical cards. If you have one slot with a microSD, it's a hybrid slot.
- 🔧 Turn on the phone and go to Settings → The phone. → All characteristics. Find the item "Quantity" SIM-map".
Pay special attention to models with support 5G. In some devices (e.g. Xiaomi) 12T) second-second SIM-The card can only work on networks 4G, even if the first one is connected to 5G. This is a hardware limitation and cannot be circumvented by software.
Physical installation SIM-maps: how to insert correctly?
It would seem that it can go wrong when installing SIM-But the wrong insertion is one of the most common reasons why the second SIM is not identified:
1. Turn off the smartphone before removing the tray. This will prevent damage to the contacts.
2. Find a hole to remove the tray (usually on the top or side face). Use a clip or a special key from the kit.
3. carefully remove the tray and place SIM-map:
- If the slot is hybrid, choose a priority: either two. SIM-card SIM + microSD.
Make sure the microchips are facing down and the bevelled corner of the card matches the angle on the tray.
4. Insert the tray back before the click and turn on the phone.
Typical errors:
- 🚫 Use micro-SIM or mini-SIM without an adapter (only nano-SIM is needed).
- 🚫 The parties are confused. SIM-The chip must be on the bottom).
- 🚫 The tray is not inserted to the end (check if there is a backlash).
Is the phone off?|Is there a paper clip to remove the tray?|Are the dimensions the same? SIM-nano-SIM?|Is the chips properly targeted?-->
After installation, the second SIM-The card is not determined, try restarting the device or slightly moving the tray (sometimes the contacts are oxidized). If the problem remains, read the next section about the software settings.
Activation second SIM-card MIUI
Even if SIM-The card is physically installed, it needs to be activated in the system. MIUI This is done through the settings menu. This is the instruction for all current firmware versions (MIUI 13/14 Android-based 12/13/14).
1. Open Settings. → SIM-maps and mobile networks.
2.Slip on the title of the second SIM-maps (it can be displayed as "SIM 2" or "Unknown SIM").
3. Turn on the switch at the top of the screen (if it is gray, the SIM is disabled).
Set the parameters:
- Name. SIM-Cards (e.g., "Worker" or "Personal").
Network type (auto, 4G, 3G or 2G – choose depending on the carrier coverage).
Priority for calls (you can specify which SIM will be used by default).
The important point is that if the second SIM-The card is not activated, check if the "Only one" mode is activated. SIM-This mode can automatically shut down when the battery is low (to save energy).
What to do if there is no second setup SIM-map?
Setting priorities: which ones SIM-The card will be used by default?
One of the key pieces MIUI Flexible management of priorities SIM-You can ask what SIM will be used for calls, SMS This is especially useful if you have one SIM for work (with unlimited calls) and the second for the Internet.
How to set up:
1. Go to Settings. → SIM-maps and mobile networks → Priority SIM-map.
2. Select actions and assign SIMs:
- 📞 Calls (you can choose "Always ask", "SIM 1" or "SIM 2").
- 💬 SMS (similarly).
- 🌐 Mobile data (it is important to specify a SIM card with a favorable tariff for the Internet).
If you choose to “Ask Always” every time you call or send a call. SMS The system will offer to choose SIM-It's convenient, but it can be annoying. To turn off this request, go back to the settings and select the default SIM.
Hidden function: in some firmware MIUI There is an option "Use the second". SIM-It automatically switches mobile data to the second SIM if the first one loses communication. To find it, open Settings. → SIM-maps and mobile networks → Additionally. → Data switching.
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If you have unlimited internet on one SIM, but it does not catch the network well, set up an automatic switch to the second SIM in case of loss of signal, this will save you from breaks during important calls or streams.
5 Problem Solving: Why the Second SIM-card?
If you did everything according to the instructions, but the second SIM-The card still does not catch the network, is not determined or is disconnected arbitrarily, the reasons may be the following:
| Problem. | Possible cause | Decision |
|---|---|---|
| SIM-map not defined | Chip or contacts damaged | Try inserting the SIM into another phone, and if it doesn't work, replace it with the operator. |
| No network on the second SIM. | Wrong APN settings | Download operator settings automatically to Settings → SIM-map → [choose SIM] → Access point (APN). |
| SIM-The card shuts down itself. | Savings in battery charge | Turn off Settings. → Battery → Saving charge → Limitation of background activity for SIM-manager. |
| You can’t use 5G on the second SIM. | Hardware limitation of the model | Check out the device specs – some Xiaomi only support 5G on the first slot. |
Additional steps for diagnosis:
- 🔄 Restart your phone in Safe Mode (hold the power button) → "Safe Mode Restart. If the second SIM is running, the problem is in the third-party application.
- 📲 Update the firmware MIUI Up to the latest version (sometimes with Dual bugs) SIM patch-fix).
- 🔧 Reset network settings in Settings → SIM-map → Resetting network settings.
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If the second SIM-If the card is unstable, check it on another phone first. If the problem persists, it's the operator's fault or the SIM's fault. If the other phone is okay, look for the reason in Xiaomi's settings.
If none of these methods helped, it may be faulty. SIM-a tray or controller on the motherboard, in which case contact the service center.
6. battery saving when using two SIM-map
Two active SIM-The cards increase battery consumption because the phone is constantly scanning the networks of two operators. MIUI There are features that help optimize energy consumption without losing functionality.
Savings:
- 🔋 Turn off background network scanning for second SIM-maps: Settings → SIM-map → [choose SIM] → Additionally. → Network scanning in the background.
- ⚡ Turn on "Only one" mode. SIM-map "for the night: Settings → Battery → Regimes → Night mode (select which SIM will be active).
- 📶 Turn off automatic network search for the second SIM-If you rarely use it: Settings → SIM-map → [choose SIM] → Searching the net → Manually.
Another life hack: if you need a second one SIM-Call-only card, turn off the mobile Internet for it, and that's going to cut battery consumption by 10 to 15 percent. → SIM-map → [choose SIM] → Mobile data.
Xiaomi models with Snapdragon 8 Gen 2 processor (such as Xiaomi 13 Ultra) have hardware optimization for Dual SIM that reduces power consumption by 20% compared to older chips. If you often use two SIMs, pay attention to this nuance when choosing a new smartphone.
7. Features of Dual SIM on different Xiaomi models
Not all Xiaomi smartphones work the same with two. SIM-Here are the key differences for the popular series:
Redmi Note 10/11/12:
Hybrid slot (SIM + microSD)
- Second second SIM-The card only works on the network before 4G (even if the first one is connected to 5G).
Support for VoLTE only on one SIM at a time.
POCO F3/F4/F5:
Two independent slots for nano-SIM (no hybrid slot).
Full 5G support on both sims (if the operator provides such an opportunity).
- Function “Dual” 5G Standby” (simultaneous operation of two 5G-standby).
Xiaomi 12/13/14 series:
- eSIM support (one physical and one virtual can be used) SIM-map).
Automatic switching between SIMs when signal loss occurs.
Dual SIM Dual Standby (DSDSDS) option with improved energy efficiency
If you are planning to buy a new Xiaomi smartphone and you are critical to work with two SIM-With cards, pay attention to models with independent slots (no hybrid solution) and support for Dual VoLTE. This ensures stable operation of both sims without compromise.
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In 2026, Xiaomi began implementing eSIM support in budget models (like the Redmi Note 13 Pro+).This allows you to use two SIMs without a physical second slot, but check if your carrier supports eSIM.