The protection of personal data on a smartphone begins with basic security measures, and PIN-code SIM-The cards are one of them, even if your Xiaomi Redmi is yours. 4X fall into the wrong hands, the attacker will not be able to use mobile communications or access the Internet SMS It's a function that many users ignore, but many people think it's unnecessary or inconvenient.
Actually, activation. PIN-The code takes no more than 2-3 minutes, and the benefits of it are obvious: protection from unauthorized calls, blocking access to mobile banking through the Internet. SMS, Preventing data theft when you lose your phone. In this article, we'll discuss how to turn on the phone. PIN-request 4X, What to do if the code is forgotten and why the standard settings MIUI They may be hiding this option.
Why do you need it? PIN-code SIM-map in 2026?
With the development of mobile technology, the risks of data theft are only increasing. PIN-Code is the first barrier to your personal information, which is why it is relevant even for low-end models like Xiaomi Redmi. 4X:
- 🔒 Lockdown SIM-- No cards for theft. PIN-The thief will not be able to use your phone number or SMS (For example, to reset passwords in banks).
- 📱 Protection against cloning SIM. Scammers may try to duplicate your card, but with active PIN-code is almost impossible.
- 💳 Mobile banking security: Many banks link transaction confirmation to SMS — PIN-code makes it difficult to access them.
- 🔄 Data retention when reselling, if you sell a phone and the buyer inserts your phone SIM-The card to another machine, he can't use it.
It is important to understand that PIN-The code doesn't protect files on your phone -- you need a lock screen password or data encryption -- but when combined with other measures like a fingerprint, it creates a robust shield for your privacy.
Preparation: What to Know Before Setup
Before activating. PIN-code 4X, make sure the following:
- Standard. PIN-It is usually 0000 or 1234, but it may vary depending on the operator (MTS, Beeline, Tele2, MegaFon.
- Standby PUK-If you enter the code 3 times incorrectly PIN, SIM-The card will be locked. You can only unlock it with the help of PUK-8 digits (code) attached to the card.
- Two. SIM-maps. 4X Supports Dual SIM — setup PIN-You will need to do the code for each card separately.
⚠️ Attention: If you have lost PUK-The code, you can only restore it through the operator (you have to show your passport). SIM-I'll have to replace the card.
Please note that after activation PIN-If you think it's inconvenient, consider alternatives like locking your screen with a password or encrypting your data in your settings. MIUI.
Step-by-step instruction: how to turn on PIN-code SIM-map
The MIUI interface on Xiaomi Redmi 4X may vary depending on the firmware version, but the overall algorithm remains the same.
- Open Settings (the gear icon on the main screen).
- Go to section. SIM-Maps and mobile networks (or dual networks) SIM mobile).
- Choose. SIM-The card you want to activate PIN (if).
- Slip on the block item SIM-maps or Install PIN-code.
- Turn on the switch Request. PIN-code.
- Enter the current one. PIN-code (default 0000 or 1234).
- Confirm the action.
Make sure the correct one is in place PIN-code|
Remember or write down PUK-code |
Check the work SIM-post-reset maps|
Synchronize contacts with Mi Account (in case of blocking)-->
If the item Blocking SIM-No map, update the firmware to the latest version MIUI. In older versions (below). MIUI (9) this section may have been hidden in Settings → Additionally. → Security.
What to do if there is no item "Blocking SIM-card"?
How to change or disable PIN-code
If standard PIN-The code seems unreliable, and you can change it to the user code:
- Go to Settings → SIM-cards and mobile networks.
- Choose the right one. SIM-Map and tap Change PIN-code.
- Enter the current PIN, then a new one (from 4 to 8 digits).
- Confirm the change.
To disable the request PIN-Return to the same section and deactivate the switch Request PIN-The system will require you to enter the current code. PIN confirm.
| Action. | Path in settings | Note |
|---|---|---|
| Enable PIN | Settings → SIM-map → Lockdown SIM-map | You will need to enter the current PIN |
| Change the PIN | Settings → SIM-map → Change. PIN-code | The new PIN must be different from the old one. |
| Turn off the PIN | Settings → SIM-map → Request. PIN-code | You will need to confirm your current PIN. |
| Unlock the PUK | SIM lock screen | A code from the kit is required. SIM-map |
⚠️ Attention: If you turn off PIN-If you lose your phone, anyone can use your code. SIM-We recommend activating it at least on the main map.
What to do if you forgot PIN-code SIM-map
The situation when PIN-The code is forgotten, and the phone requires you to enter it, which is familiar to many:
- You have 3 attempts to enter. PIN. If they all turn out to be unbelievers, SIM-card blocked.
- Unlocking PUK-Once the lock is locked, the phone will ask for PUK-- code (8 digits: 📄 On a plastic holder. SIM-maps (where the map was attached). 📑 In contract with the operator. 🌐 In the personal account on the operator's website (section "My" SIM-map").
If the PUK is lost
Important: Never enter PUK-After 10 wrong attempts, code at random. SIM-The card will be blocked and replaced.
💡
Take a picture. PUK-code and save your photo in a secure cloud storage (e.g., Google Drive with two-factor authentication) to avoid blocking problems.
Alternative means of protection SIM-maps on Xiaomi Redmi 4X
PIN-Code is not the only way to secure SIM-Map. Consider additional measures:
- 🔐 Lock the screen. Set a pattern lock, digital password or fingerprint in Settings → Lock screen and password.
- 📡 Disabling mobile data for individual applications. → SIM-map → Data traffic can be restricted to specific programs.
- 🔄 Backup contacts. Sync contacts with your Mi or Google account so you don’t lose them when you block them. SIM.
- 🛡️ Security applications. Utilities like this. SIM Card Lock (from Google Play) allows you to block SIM scheduled or geolocated.
For maximum security, combine these methods. PIN-code SIM-You can lock the screen from your fingerprint, and that creates two-tier protection.
Frequent Mistakes and How to Avoid Them
When you set up PIN-code on Xiaomi Redmi 4X Users often face typical problems. Here's how to prevent them:
- ❌ Input incorrectly PIN 3 times. Always check the numbers you enter. If in doubt, look at the standard number. PIN contract.
- ❌ Ignoring PUK-Many people throw away the packaging. SIM-losing cards PUK. Keep it in a safe place.
- ❌ Shutdown PIN You can get used to typing code when you turn on your phone in 2-3 days, and security is worth it.
- ❌ Avoid combinations like 1111 or 1234, which are easy to pick up.
Another common mistake is trying to unlock the SIM-It's not going to work: PIN and PUK tied SIM-The reset will only delete the data on the device, but it will not unlock the card.
💡
PIN-code PUK-Code is two different levels of protection. PIN It blocks everyday use. SIM-maps, and PUK It is required to unlock it after multiple errors.