The 4G network does not work. No signal, no 4G network how to solve

If the number of signal grids in the status bar of your phone is too large or sometimes too low, or when the " " symbol appears on the signal bar, it is recommended to take the following methods to try to solve the problem:

1.Whether a magnetic case, metal case, magnetic stand, or magnetic chuck cup is used.

If your phone uses a metal case, magnetic case, magnetic bracket or magnetic chuck, it is recommended to remove it and try it, as metal and magnetic materials can easily interfere with the signal and cause the phone signal to deteriorate.

2.Change your current location.

1) In some closed indoor environments, such as houses with dense spacing between buildings, the mobile phone signal may be blocked, resulting in poor signal. You can go outside to test if the mobile phone signal can return to normal.

2) The degree of network coverage of operators varies according to different regions, and urban areas basically meet the coverage, but some remote areas may have insufficient coverage capacity, which will lead to poor mobile phone signal. You can determine whether it is caused by network coverage problems by whether the mobile phone signal is poor when you are only in the same area or the mobile phone signal status of nearby friends using the same carrier** card.

3.Check that the APN settings are correct.

Incorrect APN settings will affect the normal use of the network.

2) Click the APN name to enter the APN setting interface.

3) Open the three dots in the top right corner and tap Reset to default.

4.Clean the SIM card, cross-swap card attempt.

1) Please take out the ** card to observe whether the metal surface is dirty or oxidized, it is recommended to keep the ** card clean and try it.

2) It is recommended to change to another SIM card of the same carrier, or change the SIM card to another mobile phone that supports this card before viewing. If the signal icons are all displayed as no signal, it is recommended to go to the operator's office to check and replace the SIM card with a new one.

5.Reset network settings.

If the problem persists, we recommend going to Settings, searching for Restore Network Settings, and clicking Reset Network Settings. This operation will delete Wi-Fi and Bluetooth related records, so please operate with caution.

If the problem persists after trying the above methods, we recommend that you back up your data in advance (WeChat QQ and other apps must be backed up separately) and bring the relevant purchase voucher to a nearby Huawei customer service center for testing.

According to the information you provide, you can try to turn off the phone and restart it, if it still can't be used normally, you can check the mobile phone settings Mobile Network Mobile Data Options Voice and data to check whether the default is 3G, if so, you can re-select 4G, due to the difference in the specific path of each mobile phone type, the specific use method of your mobile phone shall prevail; Check to see if you've reached the rate limit or data cap. If you still can't use 4G, it cannot be ruled out that the conditions for use are not met. At present, the following conditions need to be met to use the China Unicom 4G network:

1) The mobile terminal supports China Unicom 4G network.

2) The current location is covered by China Unicom's 4G network.

3) Use Unicom USIM card.

4) The number has 4G Internet access enabled.

If you still can't use it after meeting the above conditions, you can contact the local customer service to inquire whether the base station at your location is faulty and follow the guidelines.

If you confirm that the mobile phone signal is good, please troubleshoot as follows:

1. Please restart your phone or turn on the airplane mode, if it doesn't work, you can change the terminal for testing.

2. Please check whether the mobile access point is set to 4G.

3. The upper limit is set by the mobile phone or third-party traffic monitoring software, it is recommended to check the mobile phone settings.

4. Check whether the parameters of the mobile phone are set correctly. iPhone: Settings - General - Reset - Reset Network Settings.

If you are using a Huawei mobile phone, there are many reasons why the mobile phone does not have a 4G signal and only a 2G signal, please follow the following methods to troubleshoot:

1.If you have no 4G signal on the primary SIM card when you are using dual SIM, make sure that the supplementary SIM card is receiving MMS.

If you encounter a problem when the supplementary card receives SMS and MMS messages, the main card will display 2G:

1) You can enter the information interface, click on three dots or four dots, enter More > Settings > Advanced or Settings > Advanced, and then set Auto MMS to Off.

2) If your mobile phone supports dual VoLTE dual pass, it is recommended that you enable the Dual SIM VoLTE function: in the VoLTE network coverage area, when the dual HD icon is displayed in the status bar of the mobile phone, two cards can work at the same time.

2.Please make sure the 4G switch is enabled.

1) When installing a single SIM: Please swipe down from the top of the phone screen, open the shortcut menu, press and hold the mobile data icon, enter the settings interface, turn on Enable 4G or select 4G 3G 2G in network mode to automatically select.

3.Please move your current location.

You can consult the network coverage of the local operator, or observe the mobile phone network conditions using the same operator's SIM card nearby, if there is no 4G network in the same situation, it is generally caused by the poor and unstable 4G network coverage of the local operator, it is recommended that you try after moving to other places.

4.Please restart your phone or turn on and off the airplane mode to prepare quietly.

The special configuration of some networks may cause your phone to be unable to return to the 4G network for a short period of time, but it can be restored after restarting the phone or turning on the airplane mode.

5.Please reset the APN

Incorrect APN settings will affect the normal use of the network.

It is recommended that you open Settings, enter APN in the search bar at the top, click Access Point Name (APN) to jump to the mobile data settings interface, click the Access Point Name (APN) again, then click the three dots in the upper right corner, and select Reset to Default Settings.

6.Please reset your network settings.

7.Please remove the SIM card.

1) If your mobile phone card is manually cut card, it may affect the signal reading due to non-standard shape and poor contact, it is recommended that you bring your personal ID card to the operator's business office to apply for a standard mobile phone card.

2) Dirty or oxidized SIM cards will also affect the reading of signals, so it is recommended that you keep the SIM card clean.

8.It is recommended to update to the latest system version in a timely manner.

If your phone still only has a 2G signal, contact Huawei Consumer Service** (950800), back up your data in advance (third-party apps such as QQ and WeChat need to be backed up separately), and bring your purchase voucher to a nearby Huawei Customer Service Center.

Boarding service. Repair spare parts** inquiry.

Huawei Customer Service Center.

If the mobile phone cannot access the Internet normally, you can troubleshoot according to the following conditions:

Situation 1] The contact between the SIM card and the metal contacts of the mobile phone is insufficient, and the SIM card can be reinserted.

Situation 2] If the SIM card is damaged or there is a problem with the mobile phone, you can change the phone to test whether it is the SIM card or the mobile phone is faulty.

Situation 3] The current location is a signal blind zone or suddenly no signal, you can change places to test and pay attention to whether the mobile phone signal of other users around you is normal.

Situation 4] If the mobile phone card is in arrears or is shut down, you can pay off the arrears and turn it on.

Situation 5] The service is suspended due to abnormal use of the number, such as the number being used for illegal or illegal activities.

Situation 6] If the total traffic generated by the Internet reaches the ** traffic cap value in the current month, the system will automatically turn off the Internet access function, or limit the speed of the network, and the network will be automatically resumed in the next month, which shall be subject to your ** traffic cap rules.

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

Taking Huawei P40 and EMUI10 systems as examples, the specific reasons why the mobile phone cannot use 4G are as follows:

1. If the status bar above the mobile phone does not display the 4G signal or the mobile phone itself cannot use the 4G network, it may be a problem with the SIM card, if the SIM card is cut and in arrears, or the 4G service is not opened, the mobile phone will not be able to use the 4G network. If the SIM card is a special SIM card, then some special SIM will have restrictions on the use of the 4G network, for example, Unicom's special traffic card needs to manually modify the APN before it can be used, and the telecom special traffic card can only be used on the mobile phone that inserts this card for the first time4G, different SIM cards have different ways to use, it is recommended to contact the operator of the card to ask how to use it.

2. The problem of the mobile phone case, if you are using a metal mobile phone case, you can first take off the mobile phone case and try to reconnect, if the signal connection is successful, then part of the metal in the metal mobile phone case shields the signal, causing signal interference. It is recommended to replace the phone case with a new one.

This answer applies to most brands of mobile phone models such as Apple, Huawei, Xiaomi, OPPO, etc.