Redmi Phone Can’t See SIM Card
Consequences of flashing the device with new software
If the Android device does not see the SIM card after the user has flashed the device, then to fix the error, it is recommended to return to using the old software modification or repeat the process again.
Removed serial number IMEI
Each smartphone has a unique IMEI number, by which it is uniquely identified. There are times when after any user action (firmware, system update, smartphone reset to factory settings), this number is deleted from a special section of the smartphone memory, which makes it impossible to identify the inserted SIM card.
You can check the presence or absence of IMEI by typing 06 # on the smartphone keyboard. If the system does not issue any number, then IMEI is missing.
To return the device to a working state, you need to re-register the IMEI in the phone. There are plenty of instructions on how to do this on the Internet. The process itself is quite complicated for an ordinary user, therefore, with the slightest uncertainty in one’s own abilities, it is better to contact qualified specialists of the service center.
Sometimes a new smartphone model refuses to work with the “old” SIM card. In this case, it would be advisable to contact your mobile operator to replace the SIM. This service is inexpensive and takes only a few minutes.
Reasons why the phone does not see the SIM card
After reviewing the material presented below, you can get an answer to the question “why the phone does not see the SIM card?” The main reasons for this behavior of a mobile device are given and options for a way out of this situation are given.
All errors in identifying a SIM card are divided into two broad categories: software and hardware.
often than not, Android phone can’t see the SIM card due to software errors. The most common ones are presented below.
System update issues
Periodically (infrequently, but this still happens sometimes) there are problems with the operation of the mobile device after the next update of the Android operating system. In this case, there are two options for solving the problem:
- Roll back software to a previous version of system firmware.
- Wait until the next version is released, in which this “bug” will be fixed.
Blocking by the mobile operator
Often, when selling a smartphone for a special promotion, the provider can make a software lock for the device, which excludes the use of SIM cards from other operators in the device. In this case, it is difficult to unlock on your own, it is better to contact a specialist.
To avoid the above situation, when buying a phone from the aftermarket, always check its compatibility with your SIM card.
Disabled SIM card in operating system settings
The SIM card can be banally disabled in the smartphone settings. This situation sometimes happens when buying a new mobile device. To turn on the SIM, you need to do the following simple manipulations:
- Enter smartphone settings by clicking on the gear icon.
- Select “SIM cards and mobile networks” (the name of this item may differ for different models of mobile devices).
If the card is activated, but the gadget still does not see it, you can try to perform some action with it (for example, send a short text message). Sometimes this method helps to get SIM to work.
Why the phone does not see the SIM card. troubleshooting guide
Almost every user of mobile gadgets has encountered a situation when a smartphone “does not see” a SIM card. In such a situation, there is no need to panic and rush “all bad”, in the sense, drag the phone to the nearest service. The cause of the malfunction may be minor, and contacting certified specialists in this case will only empty your for a certain amount of banknotes.
Oxidation of contacts
Another reason why an Android smartphone does not see the SIM card is oxidation of the contacts on the printed circuit board inside the mobile device. In this situation, you will have to process the contacts adjacent to the SIM with some alcohol-containing liquid or cologne.
System (software) faults
SIM card and phone incompatibility
For example, you bought a super modern flagship smartphone and inserted a SIM card that you have been using for a very long time. Chances are good that the device simply will not be able to read such a SIM card. In this case, we just go to the nearest office of our operator and change the SIM card to a new one (the number will remain the same).
Enabling the SIM card
Just in case, you should check if your SIM card is turned off in the smartphone settings. For this:
- Go to the settings in the “SIM-cards”
Problems with NVRAM
NVRAM on devices with MTK processor is the area where important data is stored, including the IMEI. And if it is damaged, the IMEI is erased, and without it the smartphone will not see the SIM card.
To diagnose, we do the following:
- Enter the code 06 # in the “dialer”. If instead of IMEI we see empty windows, then the problem is NVRAM
Everything is solved very simply: we restore the old IMEI or change it to a new one. How to do this, read in another article.
The phone does not see the SIM card, what to do?
Sometimes users of smartphones based on Android OS are faced with the fact that their device stops “seeing” the SIM card or “keeps” it in flight mode, preventing them from making calls. This problem is rare, but if you learn how to fix it, then you will not be afraid of it. And how to do it, you will now find out.
Why the Android device does not see the SIM card
Conditionally, all causes of this error can be divided into two types: software and hardware. In the first case, systemic problems are to blame, in the second. mechanical malfunctions of the SIM card itself or the slot for it.
First, we have to check everything related to the system and if this does not bring the desired result, go to hardware faults.
Problem with slot and SIM contacts
If you accidentally wet your smartphone or it has been in a dusty room for a long time, then it is possible that the contacts of the SIM slot and the SIM card itself are simply dirty or oxidized. To fix this, it is enough to soak a cotton swab in alcohol and wipe the contacts here and there.
SIM problems after update
Sometimes the phone stops seeing the SIM card after you’ve installed the latest update to your firmware. In this case, it makes sense to “roll back” the updates and return to the previous version, in which the SIM worked properly. You can also reset your smartphone to factory settings, which is described in detail here.
It’s all about the SIM card
Has the SIM card been with you since the days of the dinosaurs? Then the probability of a problem in it increases significantly. Pull it out of the slot and check the gold-colored contact pad. Signs of problems: scratches and scuffs, peeling, oxidation, darkening and discoloration. all this will be the reason that the device does not see the card. If the first two cases are solved only by replacing it with a new one at the service center of the mobile operator, the last problem can be solved independently.
Use a soft eraser or cotton wool and rubbing alcohol. Better to use one thing, they are equally effective. Use the eraser to erase the darkened layer as thoroughly as possible. Alcohol applied to cotton wool should be applied for one or two minutes and then wipe the SIM contacts with a gentle motion. After that, insert the SIM card into the phone and check the functionality.
Are you using a Nano SIM card? Check if it is properly installed in the tray. It may simply shift during operation. Correct with the paper clip that comes with the kit. Better yet, pull out the entire tray and check that it is correctly set along the cut at the corner. If after that there is still no network, the card is definitely going to be replaced.
Another reason is the incorrect self-cutting of the SIM to the desired format. If you cut off the excess, then the card will dangle in the slot. The best option is to replace the card for free with the operator. Alternative to insert paper into the slot to securely fix the card.
When you pressed something wrong
The problem cannot be ruled out due to the user’s fault. Actions out of ignorance can lead to completely unexpected consequences, especially if Xiaomi first falls into the hands.
The most common problem is disabling a slot in the settings or changing the parameters for connecting a SIM card to a mobile network. You can check and fix it like this:
- Go to the “Settings” item by selecting the appropriate icon on the desktop or lowering the curtain.
- There select the section “SIM-cards and mobile networks”.
- Check the correct definition of operators in both slots.
- Select the problematic one by tapping on the operator’s name.
- Check the position of the switch “On”. Even if the SIM card can be displayed as an active card in the main menu, it is better to check if this is a firmware failure.
- If there are no problems, tap the menu item “Mobile networks”.
- Check if automatic network selection is enabled and the correctness of its name.
After these steps, in the absence of serious hardware problems, everything should work. To check the functionality, just check the invoice or call someone.
The problem is in the insides
Do not discount the purely hardware problem when Xiaomi cannot see the card. There are many reasons, since the circuitry on the board is quite complex, and includes many small elements. transistors, capacitors and SMD components. In addition, one damaged track can also cause interruptions in operation or a complete shutdown of the slot.
The GSM module is also problematic. For each SIM there is either its own dedicated one (then you can receive calls without switching the card’s activity), or a common signal receiver. It is damaged from using low-quality power devices or charging too often.
In both cases, you should not hope for an independent repair. Even if you have the necessary tools. a soldering station, solder, flux, it is better to trust the professionals and take it to the repair service, or change the device under warranty, if the time allows.
Delivery from China
The reason is common among those who like to buy smartphones from abroad. Each country has its own set of GSM frequencies with which the devices must be compatible. Chinese copies do not receive certification from Russian cellular operators, because they do not support the required communication standards.
The solution is quite simple, but radical and not all users can do it. flashing to the global ROM. It will have a different driver for the GSM communication module, which will be able to work with a wide range of frequencies and operators.
After reflashing, be sure to reset your phone to factory settings. This is done like this:
- Hold the power button until shutdown.
- Then we hold it down in combination with the volume up button for a few seconds.
- After the company logo appears on the screen, they can be released.
- In the menu, you need to select the language. English using the physical volume control buttons.
- Then. the item WipeReset, Wipe All Data and To confirm all actions, you need to use the power key.
After the end of the process, carry out a functional check. If everything is good, then such manipulations helped. Otherwise, you will have to return the phone to the seller.
What to do when Xiaomi does not see the SIM card?
I wouldn’t be surprised if we catch the day when Xiaomi smartphones will ring out of every other. In terms of price. quality ratio, comparing with analogues, this is an ideal option. But there is a hole in the old woman, and even the most advanced models are capricious. This time we will figure out what to do when Xiaomi does not see the SIM card without resorting to the help of the service center.
When the operating system lives its own life
Software “glitches” of the MIUI branded shell are not uncommon. Xiaomi users are faced with such problems:
- The OS has disabled the second slot for power saving. see how to check it in the section “When something was pressed wrong”;
- software failure. reboot or reset to factory settings will help;
- the slot is disabled due to the lack of signal reception. check the signal reception at the location;
- a failure in the firmware of the modem is a separate small program that can be reinstalled independently without changing the entire system;
- does not work after a software update or new firmware. the decision to roll back the OS to the previous version or to reflash only the software module of the modem from the old software version;
- damage to the Nvram partition after the “curve” of the firmware. restoring a part of the program from a full TWRP backup, or replacing it from the OS data of a similar model.
The last option, if other actions did not help, reflash the phone with an old version, in which the SIM was still functioning.
When the number does not work in 3G and 4G standards, you need to contact the operator for technical support.
It is quite easy to solve the problems with the fact that the Xiaomi phone periodically does not see the SIM card, unless you are faced with serious hardware problems. If you bought the device in China on AliExpress, the service offers a warranty return or exchange for a working phone. agree. The best option is to solve all the nuances and get a stably working smartphone without repair or software intervention.