Installing communication modules in a smartphone is a procedure that every owner of a new device faces, but in the Poco model X3 Pro has its own design features that require attention. Incorrect handling of the tray or the use of inappropriate tools can lead to mechanical damage to the body or contacts. In this material, we will discuss in detail how to safely remove and install the device. SIM-maps to ensure stable operation of the mobile network.
Before you start physical intervention, you need to make sure that you are using the right format cards. Xiaomi Poco X3 Pro requires Nano-SIM standard, which is the most compact to date. If your card is large or combined, it should be carefully broken down along the circuit or contact the communication salon for replacement, as inserting a larger card can irrevocably damage the reader mechanism.
It is also important to note that the device supports the operation of two SIM cards simultaneously in Dual SIM Dual Standby mode, which allows you to flexibly manage tariffs and roaming without the need for constant replacement of chips.
Preparation of the workplace and tools
To do this successfully, you'll need a minimal set of tools that usually comes with the device. The main tool is a special metal clip (key-needle) that has a pointed end. If the original key is lost, you can use a regular stationery clip, straightening one of the ends, but you need to be extremely careful not to scratch the case or break the tool inside the hole.
It is recommended to perform the procedure on a flat, well-lit surface covered with a soft cloth or towel.This is necessary so that in case the tray pops out sharply, it does not fall on the hard floor and is not lost, and also to avoid scratching the smartphone screen. Make sure that your hands are dry and clean, as fat and moisture can oxidize the contacts on the card itself or in the depth of the slot.
⚠️ Warning: Before any manipulation of the tray SIM-Although current standards allow hot replacement, power outage ensures that the system correctly recognizes new communication modules immediately after switching on and eliminates software failures in the radio module.
☑️ Preparation for installation SIM
Make sure that the golden contacts are on the SIM-The card has no visible contamination or scratches, if necessary, gently wipe them with a dry lilac-free cloth. Any dust or villi that enters the slot during installation can cause an unstable signal or a complete failure of the network.
Location of the slot for SIM-map
Unlike many modern smartphones, where slots are hidden on different faces, in Poco X3 Xiaomi's Pro engineers have placed a tray on the bottom of the device, a classic and convenient location that allows easy access to memory cards and other devices. SIM-modules without removing the protective cover, unless it is too thick.
If you flip the smartphone down, you'll see a small circular hole on the right of the Type-C charging port, which is designed to pull the tray out, and there's a speaker next to it, so it's important not to mess up the holes and try to puncture the speaker grid, which can damage it.
The tray in this model is made of plastic and has a specific shape, corresponding to the design of the rear panel, it fits tightly to the body thanks to a rubber seal, which also performs the function of protection against dust and splashes in accordance with the declared standard of moisture protection.
Step-by-step instructions for removing the tray
The process of removing the tray is the most critical step, requiring care. Take a prepared tool (clip or key) and insert its sharp end into the hole on the bottom edge. Insert the tool strictly perpendicular to the body, without skewing left or right, so as not to damage the internal mechanism of the latch.
Smoothly but confidently press the tool until you feel a slight click and spring resistance. At which point the tray should extend out of the body a few millimeters, which will allow you to grab it with your fingers. You do not need to press too hard if the tray does not come out - you may have misidentified the hole or the angle of input.
⚠️ Attention: It is strictly forbidden to use sewing needles to extract the tray, as they are too thin and can break inside the mechanism, or blunt-ended pins that can damage the insides of a smartphone. Use only specialized tools of suitable thickness.
Once the tray has appeared outside, gently pull it with your fingers behind a special protrusion until completely removed. Try not to touch the golden contacts inside the slot with your fingers, so as not to leave traces of fat, which may oxidize over time.
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If the tray is stuck and not pulled out with a light press, try swaying the tool slightly from side to side without taking it out of the hole to find the correct latch position.
Proper orientation and installation SIM-map
On the extracted tray, you'll see two slots for Nano-SIM cards. They have a bevelled angle that matches the shape of the SIM card itself. This eliminates the possibility of installing the card on the wrong side if you're careful. There's no separate microSD card slot in the Poco X3 Pro, so both slots are exclusively for SIM cards.
Place the card in the appropriate recess so that the golden contacts look downwards, towards the inside of the tray, and the bevelled angle matches the shape of the cutout. A slight finger press will lock the card in the slots of the tray. Make sure that the card lies flat and does not protrude over the edges of the tray, otherwise when inserted it can get stuck or damage the contacts.
| Parameter | Slot 1 (Internal) | Slot 2 (External) |
|---|---|---|
| Type of card | Nano-SIM | Nano-SIM |
| Support for 5G support | Yes (if available) | Yes (if available) |
| Substantive function | ||
| Hot replacement. | Supported | Supported |
After you have both cards installed (or one if you don't use the other), check the reliability of their fixation. The cards should not drip or fall out with a light shake of the tray. If the card is tight, don't force it, take it out and try to turn it over or correct it.
What to do if SIM-card not fixed?
Inserting the tray back into the smartphone
Getting the tray back in place requires correct orientation. The tray is symmetrical on only one axis, so it's important not to confuse the top and bottom. Usually there's a marking on the outside of the tray or a shape that matches the bending of the body, which helps you navigate.
Put the tray in the hole smoothly, without skewing. You should feel it coming in freely. If you feel resistance, don't push, take out the tray, flip it over and try again. Forced insertion can break the plastic guides inside the case.
⚠️ Attention: The tray must enter the case before the characteristic click and equalize with the frame of the smartphone. If the tray protrudes even a fraction of a millimeter, the tightness of the body is violated, and the device loses protection from moisture and dust, which can lead to water in contact with accidental contact.
After successfully installing the tray, turn on your smartphone.Android system with a shell MIUI It should automatically identify new SIM cards, and you may see network search notifications or input requests on the screen. PIN-code, if it is installed.
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Proper installation of the tray before clicking is a critical point, ensuring not only the operation of the network, but also the protection of internal electronics from external influences.
Network settings after installation
After switching on, go to the settings to check the status of the connection. Usually, the system automatically determines the operator's parameters, but in some cases, you may need to manually configure the APN access points for the correct operation of mobile Internet.
Settings menu → SIM-Maps and mobile networks you can choose which card will be used by default for calls, SMS and data transmission. X3 Pro allows you to flexibly configure use cases, for example, assign one card only for the Internet, and the second – exclusively for voice calls.
- 📶 Network Selection: Make sure that the network type is selected in the settings 4G/LTE or 5G maximum data transfer speed.
- 📞 Roaming: If you are abroad, be sure to enable the Data Roaming option in your specific settings SIM-Maps, otherwise the Internet will not work.
- 🔄 Switching: For quick switching between SIM cards during a call, use the pop-up menu in the “caller” interface or settings in the notification curtain.
When the phone is all manipulated, it says, “No.” SIM-If you want to use the card or "Emergency Calls Only", try to remove the tray again and erase the contacts of the card with an eraser, and check the card on the other phone to prevent malfunction of the operator's communication module itself.