How Do I Know If My SIM Card Is Bad? Symptoms, Causes, Fixes

A bad SIM card may prevent you from connecting your cell phone to a mobile network, so it’s essential to have a SIM card that works properly. But how do you know if your SIM card is good or bad?

Common problems that can indicate your SIM card is bad are memory access issues, no network, calls being interrupted, and sudden airplane mode. A good way to approach these issues is to get a SIM card reader as these devices have special diagnostic software that can help you resolve problems.

Below is some key information about how to test a SIM card, and the causes and symptoms of a bad card which you need to know about.

What are the symptoms of a bad SIM card?

Bad SIM card on iPhone

When you are using an iPhone, you may see a “No SIM Installed” message on the screen that tells you the SIM card in your phone is not working. 

Other symptoms include messages and calls being delayed, sound quality issues, and only numbers being present in the contact list (no names).

Bad SIM card on Android

Symptoms in Android phones are similar to the above. 

If your SIM is not working correctly, you may also see issues like the pin code being requested without rebooting the phone, or freezing of your phone – which can be solved by taking out the battery if it’s removable.

What are the causes of a bad SIM card?

Following are some of the most frequent reasons why your SIM card may go bad:

  • The most common cause is that your SIM card has some kind of manufacturing defect.
  • Frequent removal and insertion of the SIM card into the cell phone could also make your SIM card go bad because the process of taking out and sliding in the SIM can damage the chip lines over time. For this reason, SIM card have a finite lifespan.
  • Dust on the SIM could also cause a short circuit

How do you test a SIM card?

There are many ways to test your SIM card. The most obvious one is to make a phone call to one of your contacts and see whether the call is connected or not. 

If the call connects, your SIM card is fine; otherwise, you need to look for issues and try to resolve them (read on).

You can also check the signals of the SIM to determine whether your SIM card is working. If your phone shows signal bars at the top of your screen, then the SIM card may be fine. 

On the other hand, if an “Emergency Calls Only” message is displayed on the phone in an area where you normally get good network coverage, your SIM card may have gone bad. 

If both of these methods do not work, talk to your service provider to confirm the SIM Activation status. You can perform a manual activation by calling your network provider’s helpline to ask for the code and use that code to activate your SIM.

Sometimes your SIM will not get activated, or your phone may not connect to the mobile network even after putting in the code. It may be because the ID on the SIM is different from that on your network provider’s end. 

Make sure the SIM ID on the card matches the SIM ID that your service provider has registered to your account.

See also: What Can Someone Do If They Put My SIM Card In Their Phone?

How does a SIM card get corrupted?

There are several reasons why your SIM card may get corrupted, some of them are listed below:

  • If you tamper with the SIM chip of the SIM, you may start to see the symptoms of a bad SIM card that we have explained above.
  • Static Electricity discharge may also corrupt your SIM
  • If the SIM card gets exposed to humidity, it may get corrosion, which is bad for the SIM

How to fix a corrupted SIM card?

A SIM card is quite different from an SD card and it can not be corrupted. It can either be physically damaged or probably just needs a mild cleaning. If your SIM card is physically damaged, it is impossible to fix it and the best thing to do is to simply visit a service center and ask for a duplicate SIM card.

However, If you have some important data that you don’t want to lose, you can try to recover it by following the steps listed below:

  • In the first step, you need to buy a SIM Card reader – which will cost you only a few dollars.
  • Connect the SIM card reader to a computer and follow the installation wizard to install it on the computer. 
  • Once you are done setting up the SIM Card reader, insert the SIM into the reader. Make sure you insert the SIM by pepper cleaning it. Be careful not to damage the chip lines.
  • Once the SIM is inserted, launch the SIM card reader software on the computer and go through the steps that you want to resolve.

    For instance, if you want to recover data such as contacts and messages, you can use the software software interface to open the folder location where the data is located. Browse through the files and select the files you want to recover. Click on the “Recover” button to save your data to your laptop or PC.
  • Once you have made changes and fixed your corrupted SIM card, put the SIM back into your phone.

Can a damaged SIM card cause phone problems?

A damaged SIM card disrupts the normal functioning of your phone. If your phone is unable to connect to the mobile network (or on and off), you won’t be able to send or receive calls and text messages or access the internet.

As a result, your apps may not work properly as many require continuous access to the internet to function as intended.

You may also get recurring “Insert SIM card” or “enter pin” messages on your screen.

See also: How Do I Change My Number On My Android Phone?

Can a bad SIM card affect reception on an iPhone/Android?

A bad SIM card will affect the reception of a cell phone, and you will face issues such as delayed calling, texting, and bad sound quality when you are on call with someone.

Does bad SIM affect phone performance?

If you get the “Insert SIM” message all the time, it will impact the phone’s ability to pick up the signal (on and off) which will stop your phone from connecting to all kinds of service your network offers. 

It will also affect the performance of the phone when connected to the network.

Can a bad SIM card cause no service?

One of the main symptoms of a bad SIM card is that it may show a “No Service” or “Emergency Calls Only” notification on the phone screen. In this case, try to repair your SIM or simply replace it.

Can a damaged SIM card be repaired?

You will not be able to repair the physically damaged SIM card by yourself, but if your SIM Card is not working properly due to other reasons (see below), you can repair it by following the procedure we have explained above.

What are alternative causes of a SIM card not working correctly?

Incorrect or blocked PIN

The incorrect or blocked PIN can also stop the proper use of your SIM Card. If a PIN was set on activation of the SIM Card, and if you enter the PIN code incorrectly three times, the SIM card will be locked. You will need to go to your service provider to unlock the SIM.

SIM card placement issue

Placing your SIM Card incorrectly can also cause damage to your SIM Card’s chip lines, which as a result will cause a short circuit to your SIM.

Incorrect placement of the SIM may result from the SIM going loose in the SIM tray. Sometimes, the SIM may not be physically damaged, all you need to do is secure it correctly inside the SIM card tray, e.g. by placing a small piece of paper under it.

See also: What Happens When You Remove A SIM Card?

Data plan exceeded

When your Data plan reaches the limit, you will not be able to use the internet. This issue can be resolved by resetting the data or changing the cycle reset date from the network settings.

SIM not activated

If you have bought a new SIM and didn’t activate it, it will not be able to connect to the mobile network. You will probably see the “Emergency Calls Only” option on the screen. 

To solve this, you need to activate the SIM Card by calling the helpline of your service provider.

Incompatible network coverage

Incompatible network coverage is an issue that many users face. This keeps your SIM from connecting to the mobile network and restricts you from using internet data or making calls. 

To fix this issue: 

SIM locked device

If the device is SIM locked, it means it’s restricted to a specific provider. In this case, inserting a SIM card from another provider will not work as the card won’t be able to connect to the mobile network.

To fix this issue, you need to contact the network operator you bought the device from and ask them to unlock the device – you may have to pay for it.