Even if you have Wi-Fi coverage in most places you go, mobile connectivity is still important for many reasons. Without it, you can’t make calls, send and receive text messages, or stay online when Wi-Fi is down. Because of that, errors saying, “No SIM Available” or “Invalid SIM” on your iPhone or iPad can feel worrying. But fret not, we have multiple solutions below you can try.
Before We Begin: Test Your SIM Card in Another Device
The first thing to do is check whether the issue is with the SIM card or with your device. To do that, simply move the SIM card from your iPhone or iPad to another device. Check if you’ll get reception after a couple of minutes.
If the SIM Card Doesn’t Work In Other Devices
In case the SIM card still doesn’t work, you can consider yourself lucky since it’s just a fried SIM card. “Lucky? Why?” you may ask. The answer is simple: the problem lies in the cheapest and easiest part to replace.
1. Get a Replacement SIM Card
Contact your carrier and ask for another SIM card. You might have to pay for it, but it’s an inexpensive component. If you don’t mind losing signal for a few days, some carriers offer to send the card by mail. The fastest way to solve the issue, though, is by going to a store in person.
‘No SIM Available’ or ‘Invalid SIM’: If the SIM Card Still Works
If the SIM card works on other devices, things might get a bit tricky. Unfortunately, the problem is with your iPhone or iPad. Potential issues can range anywhere from simple software bugs to underlying hardware failure. Check below to find out which is your case and what fixes are available.
2. Enable Airplane Mode, Then Disable It
The first thing to try is a very basic disconnect/reconnect cycle. Turn Airplane Mode on, leave it like that for a minute or so, then disable it. Alternatively, you can power off your device, and then switch it back on. There’s a chance this is enough to get your SIM card working again.
3. Check for Possible Carrier Settings Update
This is actually one of Apple’s official solutions for the issue. On your iPhone or iPad, go to Settings > General > About. Under the Carrier section, check if there are any pending updates.
4. Reset Network Settings
Another alternative is to completely reset network settings. To do that, go to Settings > General > Transfer or Reset iPhone/iPad. Select Reset > Reset Network Settings. You’ll be prompted for your passcode, Face ID, or Touch ID.
The device will reboot to finish the reset. After that, your network should be available again. If it works, your iPhone or iPad won’t display invalid SIM error messages anymore.
5. Confirm Your Device Is Carrier-Unlocked
If you bought your iPhone or iPad from Apple or an Apple Authorized Reseller, it’s most likely unlocked. If you purchased it from a carrier, on the other hand, there’s a significant chance the device is carrier-locked.
Nowadays, it’s relatively easy to disable carrier locks, but some users report it may come back after an OS update. In this case, contact Apple or your carrier (the method varies depending on the company) and ask to unlock it again.
6. Check IMEI Blacklists
If you purchased your iPhone or iPad used, it may have lost its network connectivity because it was blacklisted. Blacklisting is a type of lock that uses the IMEI, a serial number tied to a device’s GSM modem.
Blacklists are used to make lost or stolen devices unusable. They can also be used for units purchased in installments or leased, assuming the original owner defaulted. Unless you can provide proof of legitimate purchase, you won’t be able to remove your device from the blacklist.
There are many websites that allow you to check if a device is unlocked. Some charge for this service, but many offer it for free. You’ll need to provide your IMEI, which can be found by typing *#06# on an iPhone. On iPad, go to Settings > General > About, it should be near the end of the page.
7. Temporary Fix: Use a Hair Dryer or Heat Gun
This may seem weird, but there’s a logic to that. A heat gun or, in its absence, a hair dryer, can help your iPhone or iPad get mobile signal again. In my defense, people have tried weirder things before, like baking MacBooks in ovens — and it worked.
Diagnosing the Issue
Firstly, go to Settings > General > About and check for the ICCID and the MEID. See if either of them fails to display correctly: showing all zeroes, a string of Xs, or nothing at all.
If this happens, there’s a chance your modem chip is faulty. Another sign is if Airplane Mode works inconsistently and temporarily.
The issue is that the metal pins that connect the chip to the device’s motherboard may have broken. For mobile devices, this connection uses a ball grid array (BGA): in short, metal microspheres are molten, then solidified in place. The goal is to heat this metal just enough for them to temporarily get somewhat re-seated.
Trying the Fix
In this case, you can try a DIY fix with a hair dryer or a heat gun. Be warned, though: this is a palliative solution for SIM card errors. It can also be dangerous if you don’t know what you’re doing, so proceed with caution.
Before heating things up, you need to locate your modem chip. The easiest way is by following a teardown guide. In this one by iFixit, for the iPhone 12 Mini, you can see the modem chips in step #11. They’re outlined in navy and light blue.
Now, point the hair dryer or heat gun at the approximate area where the modem chips are. Turn the dryer/heat gun on. Be careful not to set the heat too high or leave the airflow running for too long. Remember that there’s a battery right next to the part you’re heating up, and it can explode if it overheats.
How long will this fix last? Nobody knows. I have had stopgaps like that remain functional for weeks, while others stop working after a few hours or less. So, keep in mind this is just a makeshift solution until you can move to the next stage.
8. Have Your iPhone or iPad Serviced
After trying (or refraining from trying) the above method, take your iPhone or iPad to be serviced. You can go to an authorized Apple Service Center or even a random repair shop—this issue is so common that virtually every technician knows how to fix it.
If your iPhone or iPad’s SIM card issue is hardware-related, some repair technicians might suggest “reballing.” This advanced technique involves replacing the solder connections on the SIM card reader’s board. However, this process is typically not the go-to solution and is considered only when replacing the SIM reader isn’t an option.
As you can see, SIM card errors can be caused by many different factors. If you’re lucky, that will be just a fried card or a software misconfiguration. Else, you’ll need to bring in the big heat guns or probably have it repaired by a professional. In any case, the silver lining is that the issue is likely fixable.