The situation when a modern smartphone suddenly stops seeing the SIM card always causes panic. You are left without communication, internet and the ability to receive important notifications. Owners of brand devices Honor face this problem no less often than users of other brands. Most often, the reason lies in a banal contact failure or a software glitch, which is easy to fix on your own.
However, if simply removing and reinstalling the card did not help, the matter may be more serious. Perhaps there was physical wear of the tray, oxidation of the contacts inside the slot, or a critical error in the firmware Android. Before taking the gadget to a service center, it is worth conducting a thorough diagnosis, eliminating all possible software factors.
In this article we will analyze in detail the algorithm of actions to restore communication. We will consider both software methods for rebooting network modules and physical manipulations with the SIM card. You will also learn how to distinguish a software glitch from a hardware failure that requires specialist intervention.
Primary diagnosis and physical condition check
The first step should always be a visual assessment of the condition of the communication medium. Remove the tray SIM cards using a special paperclip or thin needle. Carefully inspect the golden contacts on the card itself: there should be no scratches, darkening or signs of oxidation.
Sometimes the problem is an incorrect installation. Make sure the card lies flat in the tray and matches the shape of the cutout. If you recently cut an old SIM card to fit Nano-SIM, the edges may be uneven, which prevents the contacts from fitting tightly to the phone reader.
⚠️ Attention: Never force the tray back in if you feel resistance. This can lead to breakage of the pin contacts inside the slot or displacement of the card itself.
Try to wipe the SIM card contacts with a soft eraser or cloth soaked in alcohol. Even a thin layer of sebum can disrupt signal transmission. After cleaning, carefully insert the tray back and check whether the network signal appears.
☑️ Diagnostics of the physical part
Software failures and rebooting of network modules
If the physical state of the card is in order, a software failure is likely. The operating system Android sometimes freezes when polling hardware, especially after an unsuccessful update or a sudden power outage. In this case, a forced reboot of the radio module helps.
The easiest way is to turn it on and off Airplane mode. This action completely de-energizes the antennas and communication modules, forcing them to reinitialize. Go to the quick settings panel, activate the airplane icon, wait 10-15 seconds and disable it.
A more radical method is to completely reboot the device. Do not use the Reboot function if it is available in the menu, but completely turn off the phone using the Power button. Wait a minute for the capacitors to discharge and turn on the device again. This will often clear temporary driver errors.
If your Honor phone is frozen at the boot stage and does not see the network, try holding the power button for more than 15 seconds to force a system restart (Hard Reset by power).
In some cases, resetting the network settings helps. This will not delete your personal files, but will return your connection settings to factory defaults. Go to menu Settings → System and updates → Reset → Reset network settings. After this procedure, you will have to re-enter passwords for Wi-Fi networks.
Equipment conflicts and testing in another device
To accurately determine the culprit of the problem - a phone or a SIM card - it is necessary to conduct cross-testing. Install your SIM card in any other working smartphone. If it is not detected there either, the problem is definitely on the side of the telecom operator or the chip itself.
The opposite situation is also possible: your phone Honor not a single SIM card is detected, even a known good one. This is a sure sign of a hardware malfunction of the device itself. The power controller or the reading slot itself may have failed.
- 📱 Try installing a SIM card from another operator in the second slot of your phone.
- 🔌 Check if the contacts inside the tray are bent when carefully examined under a bright light.
- 🔄 Test operation in the mode 2G/3G by forcibly switching the network type in the settings.
Sometimes a conflict arises due to the incompatibility of old SIM cards with new communication standards. If your card is more than 5-7 years old, the operator may recommend a free replacement at a communication store. New chips work better with modern encryption protocols used in 4G and 5G networks.
APN settings and access point parameters
Even if the phone sees the card, it may not register on the network due to incorrect access point parameters APN. This often happens when manually changing settings or installing custom firmware. Checking these parameters is a mandatory diagnostic step.
Go to the mobile network settings section. The path usually looks like this: Settings → Mobile network → Access points (APN). Your operator profile should be active here. If the list is empty or the profiles are inactive, the network will not work.
You can create a new access point manually by taking the current data on the official website of your operator. Enter the point name (for example, internet) and APN address (for example, internet.mts.ru). The remaining fields can most often be left blank or by default.
⚠️ Attention: APN parameters may be changed by telecom operators. Always check the current settings in your personal account or on the provider’s official website before entering them manually.
After making changes, be sure to restart your phone. The system should apply the new configurations and attempt to register to the network with the updated credentials. If this does not help, try deleting all access points and pressing the menu button to restore the default settings.
Hardware failures of the slot and controller
If all software methods have been exhausted, and replacing the SIM card did not produce results, this is the problem. In phones Honor, as in other smartphones, the SIM slot is a mechanical unit that is subject to wear.
A common cause is moisture or dust getting inside the case. Even microscopic oxidation on the board can break the power supply circuit of the SIM card. In this case, the phone can detect the presence of the tray, but not see the chip.
| Symptom | Probable cause | Solution method |
|---|---|---|
| Constantly writes “No SIM” | Oxidation of contacts slot | Cleaning the board with alcohol in the service |
| SIM card is detected every other time | Wear of springs in the tray | Replacing the tray or repairing the slot |
| The phone is heating up in the modem area | Short circuit in the SIM power circuit | Diagnostics of the power controller |
| Appeared after a fall | Failure of a component on the board | Soldering BGA or replacing the connector |
Independent repair in this case requires soldering skills and the presence of a microscope. Trying to disassemble the phone without experience may result in damage to the cables or screen. If the device is under warranty, any opening will deprive you of the right to free repair.
What is a power controller and how is it connected to the SIM?
The power controller (PMIC) distributes voltage between components. If the line responsible for powering the SIM slot is burned out or shorted, the phone will not be able to activate the card, even if the slot itself is intact.
Reset to factory settings as a last resort
When nothing helps, the last software argument remains - a complete data reset (Factory Reset). This action will delete all apps, photos and settings, returning the phone to its out-of-the-box state. This often eliminates deep conflicts in system files.
Before the procedure, be sure to back up important data to the cloud or to your computer. After the reset, the phone will need to be configured again. If after a clean installation of the system the problem with the SIM card persists, the probability of a hardware failure is 99%.
To perform a reset, go to Settings → System and updates → Reset → Reset all settings. Confirm the action by entering your screen unlock password. The process will take a few minutes, after which the device will reboot.
If, after a complete reset and installation of updates, the phone still does not see the SIM card, further software manipulations are pointless - a visit to the service center is required.
Why does the phone see one SIM card, but not the second?
This indicates a problem with a specific slot. Either the contacts in the second socket have oxidized, or the soldering of the connector on the motherboard specifically for this channel is broken. It is also possible that the second slot is software disabled in the dual-SIM mode settings.
Can the case interfere with the operation of the SIM card?
Yes, if the case is too thick or deformed, it may prevent the tray from closing completely. As a result, the contacts do not touch tightly. Try removing the case and checking the phone's operation without it.
What to do if it says “Invalid SIM card”?
Such a message usually means that the card is blocked by the operator, its validity period has expired, or it is physically damaged. This can also happen when using a card that does not support the current network standard in a given region.
Does unlocking the bootloader affect the operation of the SIM?
In rare cases, when unlocking the bootloader and installing a custom recovery, the EFS or NV partitions, where IMEI and network settings are stored, may be lost. This leads to a loss of communication, which is difficult to restore without a backup.