The mobile phone card is charged, the phone is not broken, but there is no signal, what s going on

If there is no signal on your phone or an emergency call prompt is displayed on the screen, it is recommended:

2.If it is a dual-SIM phone, please check whether the SIM card is activated: Settings - SIM Manager - SIM1 SIM2 - Click the SIM card icon - slide to turn on (the operation mode may be slightly different for different models of mobile phones).

3.If there is still no signal, it is recommended to turn off the SIM card and remove it, wipe the SIM card chip with an eraser, and then reinstall it.

4.If it doesn't work, try to change to another location to rule out whether it is caused by poor signal coverage in your location.

5.Try to change the network mode to 3G or 2G (do not select the auto-connect mode). Note: Some machines do not support changing the network mode.

6.Try to change another SIM card.

7.Update your phone's system version: Settings - About Phone (About Device) - Manual Update Automatic Update (Software Update System Update - Update). Note: Please back up the data (contacts, messages, **, etc.) in your device before upgrading.

If there is still no signal or emergency call is displayed after the above operations, please bring the purchase invoice, warranty card and machine to the nearest service center for inspection.

1. There is no signal or the signal is relatively poor, mainly because the signal will be affected by various factors such as terrain, landform, and high-rise buildings in the process of propagation, such as the current location is in a relatively closed place, and the signal may be affected.

2. If the mobile phone signal of other China Unicom users is normal, the following methods can be used to troubleshoot:

Method 1] Turn on airplane mode, then turn off or restart your phone and try again.

Method 2] Test of changing the phone card to change the mobile phone card to the mobile phone of a family member or friend and try again.

Feedback, we will check and deal with it as soon as possible.

The lack of signal on the mobile phone may be a problem with the SIM card, or it may be a hardware problem with the mobile phone or entering a no-service area or a place with no signal.

If you want to tell if your SIM card is broken, you can try doing this:

2. It is recommended to take out the SIM card, use an eraser to wipe the SIM chip, and then reinsert the SIM card into the mobile phone.

3. It is recommended to try to change to another SIM card. After changing, see if your mobile phone and other people's mobile phones have a signal, if there is still no mobile phone, it is a problem with the mobile phone.

4. If it still exists, it is recommended to restore the machine to factory settings and back up the data in the mobile phone in advance.

5. Call the operator who has received the card and ask the customer service to refresh the background of the SIM card.

6. If none of the above can be solved, it is recommended to take it to a mobile phone repair station for inspection.

There are several reasons why there is no signal on the phone:

1. Network problems or network can not be covered, when the network coverage is not good, it is generally located in mountainous areas, basements, elevators and when there is shielding or signal interference, there will be no signal or very weak appearance. In the process of debugging, optimization and maintenance, the network may also cause signal instability.

2. Problems with the mobile phone itself, there may be problems with the mobile phone receiver and SIM card slot. You need to go to the repair point to have a look. Of course, the factor of SIM card corruption cannot be ruled out.

No signal on mobile phone solution:

1. Check whether the mobile phone card slot or SIM card is damaged, you can insert other mobile phone cards to try, and then put the SIM card of the mobile phone itself on other mobile phones to see if there is a signal, if the card slot is damaged, it is recommended to replace the card slot.

2. If there is no signal on the mobile phone caused by network delay, you can turn on the airplane mode of the mobile phone, turn it off after five seconds, or restart the mobile phone. If the signal in the place is not good, you can't find the signal, so you can change the place and search again. It may be a problem with the local network base station, and it is recommended that you contact the network operator you are currently using.

Summary. The lack of signal on a mobile phone can be caused by a variety of reasons, including problems with the phone itself, insufficient network signal coverage, carrier network failures, etc. For your problem, the frequent lack of signal may be a problem with your mobile phone or SIM card.

The lack of signal in a mobile phone may be caused by a variety of reasons, including problems with the mobile phone itself, network signal failure, insufficient coverage, and operator network failure. In response to your problem, the frequent lack of signal may be a question from a mobile phone or SIM card.

Excuse me, but please go into more detail?

First of all, you can try to change a different SIM card to test. If there is still a signal problem after letting Zhisenguo change to a new SIM card, then it is likely to be a problem with the mobile phone itself. Secondly, you can check if your phone's signal settings are correct.

Open your phone's settings, find the "Mobile Network" option, make sure mobile data and roaming are turned on, and choose the right carrier. Also, it is recommended that you upgrade your phone system and software updates provided by your network service provider, which may resolve some signal-related issues. Finally, if none of the above methods can solve the problem, it is recommended that you contact the customer service staff of the mobile phone manufacturer or network service provider to understand the specific cause and seek a professional repair solution.

The main reason for the mobile phone card is that the mobile phone is in arrears, the card slot is loose, the system failure, the mobile phone card failure, the base station failure, and the hardware failure.

1. The mobile phone is in arrears.

If the payment is overdue, the carrier will turn off the service function of the mobile phone, and the mobile phone will be displayed as having no service. In this case, you need to settle the overdue amount and top up the credit.

2. The card slot is loose.

During the communication process, the mobile phone needs to continuously read the SIM card data in the card slot to establish a connection with the base station. If the SIM card installed in the card slot is not in good contact due to the shaking of the body, it may cause the mobile phone to fail to read the data normally, resulting in the phenomenon of no service for the SIM card. You can use the card pick-up pin to remove the card tray, check whether the SIM card and the card tray look normal, and then push the SIM card and card tray back into the card slot, and then observe the SIM card status through the system.

3. It is a fault of the high-level system of wild chaos.

If there is a bug in the system software related to the baseband chip, it may lead to weak signal and no service in the mobile phone. You can try to restart the phone system to solve the problem; If the frequency of failures is high, and each reboot lasts for a short period of time, the problem needs to be resolved by downgrading or upgrading the system.

4. The mobile phone card is faulty.

The SIM card chip is damaged due to its own reasons, so that the mobile phone cannot correctly read the encrypted data inside it, resulting in the mobile phone not being able to search the operator's network normally. After troubleshooting the card slot and software, you can try to solve the problem by replacing the SIM card with your carrier.

5. The base station is faulty.

The base station is the data exchange center of the mobile terminal, similar to the wireless router in the home. If the signal transceiver equipment in the base station fails or the server goes down, it will cause all mobile terminals in the area to be unserviced. For this kind of problem, as an end user, there is no good solution, and you can only contact the operator in time when the fault occurs.

6. Hardware failure.

When the possible faults mentioned above are eliminated, it can basically be concluded that the phenomenon of mobile phone no service is caused by hardware, which is usually manifested in the mobile phone baseband, radio frequency and antenna. For hardware problems, the inspection and maintenance work should be carried out by professionals, and it is not recommended that individuals dismantle and repair the air privately, so as not to cause greater losses. <>

1. Check the operator**.

Please check the status of your SIM card** and make sure that the SIM card is not in arrears or cancelled.

2. Confirm whether to use third-party magnetic or metal accessories.

Check whether you use metal protective shells, magnetic protective shells, magnetic brackets and other accessories, metal and magnetic materials are easy to interfere with signal reception, it is recommended that you remove the accessories to view.

3. Check whether the current environment covers the operator's network.

If you are in a closed indoor environment (such as a basement, elevator, etc.), the mobile phone signal may be blocked, resulting in no signal, and you can go to an outdoor environment to check. If you are in a relatively remote area and may not be covered by the operator's network, you can determine whether it is the cause of network coverage by using the mobile phone signal of the same operator's Duan Tongzai network in the surrounding area.

4. Check the SIM card and perform cross-card verification.

Observe whether there is dirt or oxidation on the metal surface of the SIM card, and check it after cleaning. If you use a tailor-made SIM card, it is recommended to replace it with a standard SIM card. Install the SIM card into other mobile phones that support this card for comparison test, if there is no signal, it is recommended that you consult the operator for processing.

5. Confirm whether the mobile phone supports the corresponding operator's mobile phone card;

6. Reset network settings.

Go to Settings - System Management - Backup & Reset - Reset Network Settings - Select the corresponding SIM card - Reset Settings, and then use View.

Note: Resetting network settings resets Wi-Fi, mobile data, and Bluetooth connection records.

7. Service center testing.

If the above methods fail to solve your problem, please back up your mobile phone data in advance, bring your mobile phone and purchase voucher to the vivo customer service center for testing, pay attention to WeChat***"vivo" or "vivo customer service" to inquire about the service center address**, it is recommended to contact before going to ensure that there is a staff reception before going to the past, so as to avoid delaying the precious time to run in vain.

A lack of signal on a mobile phone can be caused by a variety of issues, including problems with the phone itself or problems related to the SIM card. First of all, the problem with the cell phone signal can be caused by an issue with the phone itself. For example, if a mobile phone antenna is damaged or in poor contact, it may cause the signal to be unstable or not at all.

In addition, if the phone's hardware or software fails, it can also affect the signal quality. Therefore, if the phone keeps running out of signal, you need to first check the phone itself to make sure that it has no hardware or software issues.

Secondly, the problem of the mobile phone card is also the cause of the unstable signal. For example, if the SIM card is aged or damaged, it may cause the number of letters to be unstable. In addition, if the network signal of the carrier where the SIM card is located is not good, it may also affect the signal quality.

Therefore, if the mobile phone always has no signal, you need to check whether the hand-to-hand potato is normal and whether the operator's network signal is good.

If both of the above conditions are ruled out, then the problem of no signal on the phone may be related to the location of the phone. For example, if the mobile phone is in a dead spot or in a place with difficult terrain, the signal may be unstable. In addition, if the mobile network technology used is not advanced enough, it will also affect the signal quality.

Therefore, if the phone is always out of signal in some places, you need to consider changing the location or upgrading the network technology.

In short, the constant lack of signal on the mobile phone may be caused by a variety of reasons, which need to be carefully examined and diagnosed. If it is a problem with the phone itself, it needs to be repaired or replaced in time; If it is a problem with the mobile phone card, you need to replace the card or deal with the problem of the card in time; If it's a location or network technology issue, consider adjusting the location or upgrading the network technology. <>

The reason for the lack of signal may be a problem with the card, or it may be a problem with the phone. First of all, if you are using an old SIM card, it may cause no signal issues. If your mobile network service provider has recently changed or is faulty, it can also cause no signal issues.

Also, if your phone is outside of the zone, the signal may also become poor or break completely.

If your signal suddenly becomes unstable or disappears completely, you can try restarting your phone or uninstalling and reinstalling the SIM card. Another thing worth trying is to make sure your phone is running the latest version of the operating system, as this can fix many problems with mobile networks and signals. You may also want to consider resetting your network settings or using another network testing tool to determine what the problem is.

It should be noted that the signal strength of mobile phone combustion is greatly affected by the surrounding environment, such as in buildings, mountainous areas, underground and other environments, the signal strength may become very poor or even disappear. In this case, it is recommended that you try to test the signal in an open external environment.

If your phone and SIM card have been installed and updated as necessary, and there are no problems with the surrounding environment, then the reason for the lack of signal may be a hardware problem with your phone that needs to be repaired or replaced at an after-sales repair point. <>