Owners of Xiaomi and Redmi smartphones often think about the security of personal data, while forgetting about the very first line of defense - their SIM card. SIM-The MTS card is a critical procedure that blocks attackers from accessing your number in the event of a theft or loss of a device. Without this code, you can simply move your SIM to another phone and access bank SMS messages or instant messenger accounts.
With MIUI and the new HyperOS, the protection activation process is straightforward, but it has its own features depending on the firmware version. It is important to understand that the password is tied to the card chip, not the phone, so it will be requested every time you reboot the device or remove the card. In this article, we will discuss in detail the algorithm of actions, ways to restore access and the nuances of working with PUK codes for MTS subscribers.
Preparation for the installation of protection on the SIM card
Before you start changing the security settings, you need to make sure that the device is ready and the raw data is available. PIN-The code for MTS SIM cards is most often 1111 or 0000, but recently operators have switched to individual codes that are indicated on the plastic card holder. If you have never changed your standard settings, this information can be printed on the back of the plastic.
Make sure that the SIM card is correctly defined by the system and is in active condition. If you use a dual-sim smartphone, the procedure will be identical for each card, but you need to perform it separately for the SIM 1 and SIM 2 slot. Xiaomi allows you to flexibly manage access rights, but the basic lock is done through the Android system settings.
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Take a picture of a plastic card that holds an MTS SIM card before it's destroyed or thrown away. PUK-The only way to save the code is if you make a mistake three times. PIN.
Do not ignore this stage of preparation, as incorrect code entry three times in a row will lead to a lock card and request. PUK-Lockdown. PUK It requires you to go to the salon or use a special unlock code, which takes longer. PIN act on.
Algorithm of PIN-code installation through Xiaomi settings
The process of activating protection in the MIUI interface is logically structured and takes no more than a minute. To begin, open the main settings menu of your smartphone. Depending on the version of the shell, the desired item may be called differently, but it is usually in the section associated with the connection or passwords.
Find the Privacy Protection or Passwords and Security section, and within this menu, you will need to select the System Security subsection or go straight to Privacy. SIM-This is where the switch is hiding, which activates the password request when the device is turned on.
☑️ Installation algorithm PIN-code
After activating the slider, the system will ask you to enter the current one. PIN-Enter the code carefully, as you only have three attempts. Once you have successfully checked, you will be asked to change the code to your own, more complex and memorable, and it is recommended not to use obvious combinations like 1234 or date of birth.
⚠️ Attention: After shift PIN-When the old code stops working immediately, write the new combination in a safe place or remember it, as you can restore the forgotten personal code. PIN-code through phone settings is impossible.
Code management via engineering menu and USSD
An alternative and faster way to control the lock of the SIM card is the use of USSD-This method works on any phone, including Xiaomi, and does not require a deep dive into the settings menu. For MTS subscribers, there is a universal set of commands that allows you to change, turn on or turn off a password request.
To change PIN-code through the command line, type the following sequence on the call keyboard: **04*old_PIN*new_PIN*new_PIN# And you press the call button, and the system will instantly process the request and confirm the change of password with a message on the screen or a pop-up notification.
The 042# command is used to turn on the phone and 040# is used to turn off the password request. However, the functionality of these commands may depend on the operator’s settings and the type of SIM card (USIM or standard).
What to do if USSD-teams are not working?
Table of standard and user codes
To help you understand the differences between code types and their purpose, we have compiled a summary table that will help you avoid getting confused with the terms PIN, PUK and PUK2, which are often found in MTS documentation and the Xiaomi interface.
| Type of code | Appointment | Number of attempts | Where to find out. |
|---|---|---|---|
| PIN | Blocking access to SIM-map | 3 attempts at | Invents the user / Factory on the map |
| PUK | Unlocking after PIN errors | 10 attempts at trying | On the plastic card-holder / Personal Cabinet |
| PIN2 | Access to additional services | 3 attempts at | Factory (often 0000 or 1234) |
| PUK2 | Unlocking the PIN2 code | 10 attempts at trying | Personal account of MTS / Support Service |
Please note that the code PUK If you've exhausted all 10 input attempts, PUK-The SIM card is locked forever and cannot be restored, in which case you will have to go to the MTS salon with a passport to reissue the SIM card with a number saved.
PIN2 and PUK2 are used less frequently, mainly to limit outgoing calls to certain numbers or paid services. In modern Xiaomi smartphones, these features are often hidden or not used by users, but it is useful to know about their existence.
Actions in blocking and forgotten password
When a user forgets the set PIN-If you typed the wrong code three times, Xiaomi's smartphone will block the SIM card and request input. PUK-The lock screen will change, and the input field will change. PIN become inaccessible.
To unlock, you need to enter an 8-digit PUK-As mentioned earlier, it's on a plastic card that came with an MTS SIM card. If the card is lost, log into the MTS subscriber's account via Wi-Fi or another SIM card. The room or security settings section usually displays your personal account. PUK-code.
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Input incorrectly PUK-If you have a code that's 10 times the SIM card burns out, you'll need to be very careful when you enter the numbers, and you'll want to double-check them.
After successful entry PUK-The system will immediately prompt you to install a new one. PIN-Come up with a combination that's easy to remember but hard to match, and then you can re-enter the new code and you can re-enter the network.
Features of working with two SIM cards
Xiaomi and Redmi smartphones are famous for their support for two SIM cards, which is very popular among users.
You can set different PIN-If you turn on a phone with two secure SIM cards, the system will consistently request unlocking first for one, then for the second. The order of the request usually corresponds to the numbering of slots or the priority given in the network settings.
- 📱 Separate Storage: Locking one card does not affect the other until all phone settings are reset.
- 🔄 Changing Priority: If you swap SIM cards (from slot 1 to slot 2), Settings PIN-The code will be stored behind the card itself, not behind the slot.
- ⚙️ Default settings: In the Settings menu SIM-Cards can be selected which card is used for calls and the Internet by default, but this does not eliminate the need to enter PIN start-up.
It is recommended not to disable the password request for the second SIM card, even if it is used only for the Internet.In the case of a phone theft, attackers can try to use any active number to obtain confirmation codes.