Xiaomi’s modern smartphones have advanced security systems that can sometimes be an obstacle for the owner. SIM-It's a fairly common occurrence, it can happen after you update the system, or it's blocked by the carrier. SIM-Understanding the nature of the lock is the first and most important step to restoring access.
In most cases, the problem is solved by entering a standard PIN-It's a code that's usually 0000 or 1234, unless you've changed it before, but if you typed the wrong code three times, the phone will require you to do it. PUK-code that can't be picked up by the pumpkin method anymore. PUK-code more than ten times will lead to irreversible blocking of the SIM card, after which only the replacement of plastic from the operator will help.
There is also software locking associated with linking the device to an account or region, in which case standard code entry methods will not help, and you will need to intervene more deeply in the settings of the system or the use of specialized software, it is important to act consistently and carefully so as not to aggravate the situation and not lose important data.
Types of SIM-card locks on Xiaomi
Before you start active action, you need to clearly identify the type of lock. MIUI There are three main scenarios: the blockage itself. SIM-Card protection (anti-theft), device screen lock (pattern lock, fingerprint) and network lock by the operator.
Lockdown SIM-The card is a security feature built directly into the operator's chip, and it doesn't depend on the phone model. PIN-code, so the security is activated at the SIM level, but if the phone says "Void." SIM-Map or Emergency Calls Only, the problem may be network settings or hardware compatibility.
Regional restrictions are also worth mentioning: some versions of CN firmware (Chinese) may not work properly with European operators without first unlocking the bootloader and flashing it to the Global version.
What is the difference between PIN and PUK?
Unlocking through PIN and PUK codes
The most common scenario is the requirement to introduce PIN-If you remember your code, just type it in. If you forget it or lose it, the system will ask you to enter it. PUK. This code is unique to each SIM-cards and not tied to a Redmi or Poco phone.
Where to find out. PUK-It's usually printed on a plastic card that you used to break your SIM card from when you bought it, and if you didn't have any plastic, you can find it in the operator's personal account on the website or on the mobile app, and you can also get it by calling customer support from another number.
You enter the code through the standard dialog box. Be very careful: you only have 10 attempts. SIM-The card will be permanently blocked, and the number can be restored only by re-releasing the SIM in the operator's office with the preservation of the number.
☑️ Algorithm of actions when requesting PUK
⚠️ Warning: Never try to guess. PUK-The probability of guessing an 8-digit number is almost zero, and the risk of losing a number becomes absolute after 10 attempts.
After successful entry PUK The system will ask you to install a new one. PIN-It is recommended to choose a combination that is easy to remember, but difficult to find. Write this code in a safe place or use a password manager to avoid a repetition of the situation.
Reset network settings and operator profile
Sometimes the lock is software-based, and the smartphone can forget the operator's settings or get conflicting data when you change region, and then reset the network settings effectively, and this action will not delete your personal files, contacts or applications, but return the connection settings to factory values.
To do this, go to the settings menu. The path may vary slightly depending on the version of MIUI, but the general logic is maintained. Find the partition that connects and shares data. You want to find the reset button here.
Once you press a button, the phone can reboot. This is normal behavior. Once you turn on, check if the unlock request has disappeared or if the network signal has appeared. If the problem was a configuration failure, it should be resolved.
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Before resetting your network settings, take screenshots of important settings, such as APNs, if you’re using the corporate internet or specific MMS settings.
In some cases, manual updates to the operator profile help. SIM-Select the desired SIM and find the option "Update profile" or "Operator settings." The system will try to download the current configuration files from the server.
Use of engineering menu and special codes
For more advanced users, there is an option to use the engineering menu, which is a hidden part of the system, designed for testing equipment and diagnostics, which can check the status of the network lock and, in some rare cases, change the parameters of the region.
The most common code for devices based on MediaTek and Qualcomm processors is ##4636##. Enter it in the dialer and the menu should open automatically.
In the menu that opens, select "Phone Information." Here you can see the status. SIM-maps, signal strength and network type, sometimes switching network mode, such as from "LTE Only" on "GSM/UMTS/LTE This can shake the communication module and remove the software block.
| Team team. | Function | Works on |
|---|---|---|
| ##4636## | Test menu | Android |
| *#06# | IMEI verification | All phones. |
| ##3646633## | MediaTek Engineering Menu | Xiaomi (MediaTek) |
| ##6484## | CIT Menu (Tests) | Xiaomi (Global) |
Using codes doesn't require root rights, but it requires caution. Changing unknown parameters in the engineering menu can cause the modem to run unstable, and if you're not sure what the parameter is, you better not touch it.
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The engineering menu is a powerful diagnostic tool, but it's not a panacea, and it doesn't remove operator locks if the phone is locked to a specific network.
Unlocking with Mi Account and Find Device
If your phone is locked at the account level (activation screen after reset), you'll need access to Mi Account, which is the theft protection that ties the device to the owner's account. Without the password from the account, you can't officially unlock the phone.
You need to go to mi.com and log in to your account. Find your smartphone in Devices. If your device is online, you can try to remotely unlock it or erase it. However, if Find Device is enabled, you can't delete it without a password.
For a forgotten password from Mi Account, use the recovery procedure via email or phone number linked to an akka. This is the only legal way to reclaim access. Bypassing this protection through flashing often leads to IMEI blocking on Xiaomi servers.
⚠️ Note: Using third-party software to kick out a Mi Account is a violation of the terms of use and can turn your phone into a brick after another security update.
What to do if the phone is locked under the operator (SimLock)
The situation when the phone is bought abroad (for example, in China or the United States) and locked up under a specific operator (AT&T, T-Mobile, China Mobile), is one of the most difficult, in which case the SIM cards of other carriers do not work, and the phone requires a code to unlock the network.
The official route is to contact the operator whose network the device is locked in, and if you have fulfilled the contract or paid for the device in full, the operator must provide the unlock code for free, and this will require the device's IMEI.
If the operator refuses or the device is bought with no guarantee of unlocking, there are paid services, there are codebases that can generate an unlock code for a fee, and be careful: many generator sites are fraudulent.
The alternative is to use software patches or crutches that emulate the SIM card of the right operator, a temporary solution that may stop working after a firmware update. Full unlocking of the bootloader and reflashing to the global version sometimes helps, but not for all models.