Installing a sim card in a Xiaomi smartphone seems like a simple procedure, but in practice, many users face difficulties, from a jammed tray to an improperly cropped SIM. Especially relevant problem for owners of new models Redmi Note 13 Pro+ or POCO F6, where the manufacturer uses combined slots for two nano-SIM + microSD or hybrid solutions. In this article, we will analyze not only the basic instructions, but also the nuances for different generations of devices, and also tell you how to avoid breakage of contacts with a careless installation.
It is important to understand that the process differs depending on the type of slot: the classic retractable tray (as in Xiaomi 14) requires one approach, and the hybrid slot (for example, in the Redmi A3) – another. We will also touch on the issue of SIM compatibility: why micro-SIM is not suitable for modern smartphones, how to properly trim the SIM in the home, and what to do if the tray is stuck inside the case. For clarity, we will give a comparative table of slot types by model and add video instructions for visual perception.
Types of SIM cards and slots in Xiaomi smartphones
Since 2018, all Xiaomi smartphones have been using the nano-SIM (4FF) format exclusively, which means that if you have an old-style SIM (mini-SIM or micro-SIM), it will have to be cropped or replaced from the operator.
By type of slots, the devices are divided into three categories:
- 📱 Classic tray – supports 2 nano-SIM + microSD (e.g. Xiaomi) 13T, POCO X6 Pro) The tray is extended by means of a paper clip.
- 🔄 Hybrid slots: 2 nano-SIM or 1 nano-SIM + microSD (e.g. Redmi Note 12) requires a choice of priority: either a second SIM or a memory card.
- 🆕 Embedded slot – rarely found in new models (e.g. Xiaomi) MIX Fold 3), where the sim is installed without a tray, under the back cover.
Before buying a SIM, check the specifications of your model on the official Mi.com website or in the documentation. For example, Xiaomi 14 Ultra supports Dual SIM Dual Standby (DSDSDS), which allows you to use two SIMs at the same time, but not all operators work correctly in this mode.
Preparation for installation: what will be needed
To avoid damage, prepare the following tools and materials:
- 📎 Paperclip or needle - comes with a phone (usually in a documentation tray) If you lost it, an unbended paperclip will do.
- 🔍 Lantern - will help to consider the slots of the tray in poorly lit places.
- 🧲 Magnet (optional) – if the tray fell inside the case, the magnet will help to remove it without disassembling the phone.
- 📱 SIM card for testing if the main one is not recognized.
Safety warning: Never use metal objects (knives, forks) instead of a paper clip - this can damage the tray sealing ring or SIM card contacts. Also avoid removing the tray when the phone is on: in rare cases, this leads to short circuit contacts.
Turn off your smartphone (required!)|Check the SIM card format (nano-SIM only)|Prepare a paper clip or a special key |Make sure the tray is clean (no dust/sand)|Check the integrity of the SIM card contacts-->
Step-by-step: how to insert the SIM in the tray
Follow this algorithm for most Xiaomi models (except for embedded slots, more on them below):
- Turn off the phone. This will prevent the contacts from being damaged when you install them. Press and hold the power button, then select Turn off.
- Find a SIM card slot, which is usually on the top or side of the card (e.g., in the POCO F5 on the right, in the Redmi 12 on the left), and on some models, the slot is hidden under a plug, you need to nail it.
- Put the paperclip in the hole before you click. The tray should extend 2-3 mm - do not pull it by force, otherwise you will break the mechanism.
- Remove the tray completely and place it on a flat surface. Pay attention to the slots and marks: usually on the tray there are schemes where to insert the SIM (contacts down!).
- Set the SIM card in the appropriate slot. For hybrid slots, select priority: If you need a memory card, insert it instead of the second SIM.
- Put the tray back before you click. Make sure it sits flat, and the skews will lead to poor contact.
- Turn on your phone and check the network. If the SIM doesn't recognize you, remove the tray and repeat the installation.
Critical error: if the tray is not fixed after installation, then the SIM card is not installed by the tags or skewed, and continued operation in this condition will damage the motherboard contacts!
What to do if the tray is not moved?
Features for models with embedded slot
Some flagship models (such as Xiaomi MIX Fold 3 or Black Shark 5 Pro) use embedded slots without a tray, in which case the SIM card is installed under the back cover, and the process requires carefulness:
- Turn off the phone and remove the back cover (a plastic shoulder blade or mediator will be required).
- Find a SIM card slot – it’s usually located next to the battery and marked with the SIM symbol.
- Carefully insert the SIM contacts down, then fix it with a metal latch.
- Make sure that the SIM does not protrude beyond the edges of the slot, otherwise the lid will not stand in place.
⚠️ Warning: When you disassemble your phone, you lose your warranty! If you are not sure of your abilities, contact the authorized Xiaomi service center. Also remember that embedded slots often do not support hot-swap (replacement of the SIM without turning off the phone).
Common Mistakes and How to Avoid Them
Even experienced users sometimes make mistakes when installing a SIM card, and here are the most common ones and ways to solve them:
| Mistake. | Reason. | Decision |
|---|---|---|
| Simka's not recognizable. | Incorrect installation (contacts up) or contamination of contacts | Turn the SIM over, wipe the contacts with alcohol |
| The tray is not fixed. | Simka stands for edges or skewed | Check the flatness of the installation, if necessary, trim the sim |
| The phone says "no net" | Damage to the SIM card chip or operator problems | Try another SIM or contact the operator |
| The tray is stuck inside. | Broken nominating mechanism | Use a magnet or contact the service |
One of the most insidious problems is the oxidation of the SIM card or slot contacts, and if the phone has been in a wet environment for a long time (like a bathroom), the contacts could be covered with plaque.
- Remove the SIM and the tray.
- Wipe the contacts of the SIM and slot with a cotton swab dipped in isopropyl alcohol.
- Let it dry for 5-10 minutes before re-installation.
💡
If you change your SIM cards frequently (e.g. when traveling), buy a magnetic-fixed tray adapter that will prevent the SIM from slipping when shaking your phone.
How to trim a SIM card to nano-SIM at home
If you can't replace the SIM from the operator, you can cut it yourself.
- ✂️ Sharp scissors or a stationery knife
- 📏 Line or template for cropping (can be printed from the Internet)
- 🧼 Sandpaper (fine-grained) for grinding edges
Step-by-step:
- Put the SIM on the template and circle the nano-SIM circuit with a marker.
- Carefully trim along the line, leaving a stock of 0.5 mm.
- Grind the edges with sandpaper so that they do not scratch the tray.
- Check that the chip is intact and the contacts are intact.
⚠️ Warning: If the SIM does not work after pruning, do not try to "fit" its size with a file - you risk damaging the chip.
💡
Self-trimming of the SIM card cancels the operator's guarantee for its operation, and if the SIM card ceases to function, you will have to buy a new one for the full cost.