Owners of Xiaomi Poco X3 Pros often face the need to install or replace SIM-The card, whether it's when you first switch on your smartphone, change your operator, or recover from a reset, has nuances despite its apparent simplicity, from choosing the right size to carefully removing the tray without damage. In this article, we will analyze all stages of installation – from tool preparation to network verification, and also consider typical errors that can lead to a lack of signal or slot failure.
The Poco X3 Pro features a hybrid slot that supports either two nano-SIMs or one nano-SIM+ microSD card. This means that using two sims you won’t be able to expand memory, and vice versa. We’ll explain in detail how to determine the configuration of your tray and what to do if the smartphone doesn’t see the card after installation.
If you have just purchased the Xiaomi Poco X3 Pro or are considering changing carriers, this guide will help avoid common problems, such as many users trying to insert the SIM with the back side or using excessive force when closing the tray, which can damage contacts, we will show you how to do this correctly and safely, and we will give tips on choosing a SIM card and troubleshooting.
Preparation: What you will need before installation SIM-map
Before you start the installation, make sure you have everything you need. Here is the minimum set you will need:
- 📱 Xiaomi Poco Smartphone X3 Pro (off!) Installing a SIM in the device on can cause the network to crash.
If you plan to use two SIM cards, make sure that both support the nano-SIM format. Note: Poco X3 Pro does not support eSIM, so a physical card is mandatory. Also check if the SIM is activated from the operator - sometimes new cards require pre-registration via the Internet or a call.
The Poco X3 Pro tray has a special microSD slot, but it can't be used with two SIMs at the same time, so if you need extra memory, you'll have to sacrifice a second SIM card.
Where is the slot for SIM-POCO X3 Pro
In Xiaomi Poco X3 Pro, the SIM card tray is located on the left side of the smartphone — about halfway between the volume buttons and the USB-C connector. It is easy to recognize by the small clip opening. If you hold the phone with the screen to yourself, the slot will be on the bottom left.
The exterior of the tray is a metal plate with a slot for the tool. It has no inscriptions or tags on it, so focus solely on the shape. It's important not to confuse it with the microphone hole, which is just above.
To make sure you find the right spot, flash a flashlight – inside the hole, you should see a metal mechanism (spring) that holds the tray. If you are not sure, compare with the photo below (or watch the video at the end of the article).
What does the tray look like inside?
Do not try to open the tray with a nail or a sharp object - this can scratch the body or damage the mechanism. Use only a clip or a brand key from the kit.
Step-by-step instruction: how to insert SIM-map
Now, let's get to the process itself. Follow the instructions in order to avoid errors.
- Turn off your smartphone. It's a must! Installing a SIM on your device can damage your contacts or cause your modem to malfunction.
- Insert the paperclip into the hole on the tray and press slightly until you feel the click. The tray should extend 2-3 mm - after that it can be carefully pulled out with your fingers.
- Place the tray on a flat surface. Notice the tags inside the socket, which show which side to insert the SIM, and the map should have a cut corner (skis) that matches the shape of the slot.
- Install the nano-SIM in the selected slot (top or bottom). The card should lie face up (contacts to the back of the phone). If you use two SIMs, repeat the action for the second slot.
- Carefully insert the tray back into the smartphone to the point. Make sure it sits flat - if you feel resistance, do not press, but check the correct installation of the SIM.
Once the phone is turned on, it will automatically determine the new SIM cards. If this does not happen, go to Settings. → SIM-maps and mobile networks and select the desired settings (network priority, roaming, etc.).
Simka lies cut corner to top of tray |
SIMKA contacts face down (to the back of the phone)|
The map fits tightly to the stops and does not hang |
The tray is inserted without effort and is not skewed-->
⚠️ Attention! If the phone doesn't see the network after you set the SIM, don't try to retrieve the tray right away. APN (Often the problem lies in the wrong operator parameters, not in the map itself.
How to properly trim SIM-nano-format
If you have an old-style sim, either a mini or a micro, you can cut it to nano-size yourself, and you need a template (on the Internet) or a special cutter. Here's how to do it safely:
- 📏 Put the template on the SIM so that the bevel coincides with the label on the template.
- ✏️ Circle the contour with a pencil or marker.
- ✂️ Carefully trim the excess with scissors, leaving a reserve of 0.5 mm.
- 🧼 Clean the edges with sandpaper (so as not to scratch the slot).
If you doubt your skills, it is better to contact the communication salon - there you will be replaced for free with a nano-format in 5 minutes. Incorrect pruning can lead to the card not contacting the slot or getting stuck inside.
⚠️ Attention! Do not use a knife or blade to trim - this can damage the SIM card chip. Also do not try to insert the cropped card into the tray without checking: first make sure it freely enters the template.
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If you don't have a template, you can use the old nano-SIM as a stencil, just put it on a new map and circle it around.
What to do if your phone can’t see SIM-map
Sometimes, after you set up a SIM, your smartphone doesn't recognize it, and the reasons can range from a misinstallation to a hardware malfunction.
- Check if the SIMKA is inserted correctly (slip up, contacts down).
- Restart the phone. Sometimes the modem doesn't initialize the first time.
- Try inserting the SIM into another slot (if you use two cards).
- Make sure that the SIM is activated by the operator (call from another phone to her number).
- Check the settings. APN: Go to Settings. → SIM-maps and mobile networks → [choose SIM] → Access points (APN) Choose your operator profile.
- Update the smartphone software: sometimes bugs in the firmware interfere with the correct operation of the modem.
If nothing works, try inserting the SIM into another phone, if it doesn't work there, there's a problem with the card (possibly a chip is damaged), if it works, the Poco X3 Pro slot is faulty, and you'll have to go to the service center.
Another rare but possible scenario is that the slot contacts are contaminated, in which case you can gently wipe them with alcohol or erasing (no fanaticism!).
| Problem. | Possible cause | Decision |
|---|---|---|
| The phone doesn't see SIM. | Incorrect installation | Reinstall the map, check the bevel |
| No network (only emergency calls) | Non-activated SIM | Activate through the operator |
| SIMCA is defined, but there is no Internet | Wrong APN settings | Reset APN settings or manually enter |
| The tray is not fixed. | Dirt got or map set crooked | Clean the slot, reinstall the SIM |
Can we use two? SIM-MicroSD cards and microSD cards simultaneously
No, Xiaomi Poco X3 Pro cannot use two SIM cards and a memory card at the same time. The tray is hybrid: it supports either two nano-SIMs or one nano-SIM + microSD.
- If you insert two SIMs, the microSD slot will be locked.
- If you use a SIM + microSD, the second SIM slot will become unavailable.
This limitation is due to the design of the tray, and if you need both SIMs and additional memory critically, consider:
- 📱 Use Google Drive (Mi Cloud) instead of microSD.
- 🔄 Regularly transfer files to your computer.
- 📦 Buy a smartphone with a separate microSD slot (e.g. Redmi Note 10 Pro).
⚠️ Attention! If you try to insert two SIMs and a microSD at the same time (for example, by cutting the tray), it can lead to damage to the contacts or short circuit!
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In the Poco X3 Pro, you can choose only one option: either two SIMs or a SIM + microSD. You can not use three cards at the same time.
Tips for caring for a slot for SIM-map
To avoid problems with the SIM card in the future, follow the simple recommendations:
- 🧴 Regularly (every 3-6 months) clean the slot from dust with compressed air or a soft brush.
- 💧 Avoid getting moisture into the tray. If the phone is wet, don't insert a SIM until it's completely dry.
- ⚡ Do not remove the tray when the phone is turned on - this can cause a modem malfunction.
- 🔄 If you do not use the second SIM for a long time, remove it from the slot to avoid oxidation of contacts.
If you change your SIM cards frequently (for example, when traveling), you should buy a spare tray, which can be bought on AliExpress or at Xiaomi service centers, which will save the original tray from wear and tear.
Also pay attention to the quality of the SIM card. Cheap cards with thin plastic can break when extracted or scratch the slot contacts. It is better to use SIM cards from trusted operators (MTS, Beeline, Tele2, MegaFon).