如果您忘记将SIM 卡(SIM card)放入 iPhone，您的 iPhone 很快就会注意到。毕竟，如果没有那一小块金属和塑料，您将无法发送任何短信、拨打电话或使用蜂窝数据。但是，如果 iPhone在里面有 SIM 卡时显示“未安装 SIM 卡”怎么办？(No SIM Card Installed)
许多因素（例如有故障的蜂窝无线电、过时的运营商设置或损坏的 SIM 卡）都可能(SIM—can)导致屏幕上弹出“未安装 SIM 卡”错误。然而，大多数时候，原因是微不足道的，您可以迅速解决问题。
下面的故障排除提示和修复列表应该可以帮助您修复 iPhone 上的“未安装 SIM 卡”错误。
打开/关闭飞行模式
在极少数情况下，iPhone 中与网络相关的组件会无缘无故地出现异常行为。toggling Airplane Mode ON/OFF让它再次工作。
首先打开iPhone 上的“设置”应用。(Settings )然后，打开飞行模式(Airplane Mode)旁边的开关，等待至少五秒钟再将其关闭。
这应该会重新启动 iPhone 的网络设备并使设备能够识别SIM卡。
重启 iPhone
如果您的 iPhone 在Airplane Mode ON/OFFSIM卡”错误，那么最好重启设备。这应该可以解决阻止其识别内部SIM卡的小故障或异常。
使用面容 ID 重启 iPhone(Restart an iPhone With Face ID)
一个接一个地快速(Quickly)按下和释放 iPhone 的提高音量(Volume Up )和降低音量(Volume Down )按钮，然后立即按住侧面(Side )按钮。然后，将电源(Power)图标向右拖动以关闭设备。
等待(Wait)30 秒，然后再次按住侧边(Side )按钮以打开 iPhone。
使用 Touch ID 重启 iPhone(Restart an iPhone With Touch ID)
按住 iPhone 的侧边(Side)/顶部(Top )按钮并将电源(Power)图标拖到右侧以关闭设备。然后，等待 30 秒并再次按住侧面(Side)/顶部(Top )按钮以重新启动它。
弹出 SIM 卡并重新插入
你的 iPhone 掉了(Did you drop your iPhone)吗？这可能最终会敲打SIM卡，因此最好将其弹出并重新插入。
使用 iPhone 随附的SIM 卡(SIM)弹出工具（也可以使用回形针）移除SIM卡托盘。您应该在 iPhone 的右侧找到它，但如果您使用的是 iPhone 12 或更新版本，请改为查看左侧。
然后，取出SIM卡，将其重新正确放置在SIM托盘上（使用卡和托盘上的槽口进行引导），然后将其滑回 iPhone。
清洁 SIM 卡
如果您有定期在设备之间更换SIM卡的习惯，它可能最终会沾上一层污垢。你应该清理它。
尝试用柔软的干布擦拭SIM卡，然后擦拭SIM卡托。(SIM)这应该可以消除阻止SIM卡连接器与 iPhone 接触的灰尘和污垢。
用几股压缩空气清除SIM 卡插槽中的碎屑也是一个好主意。(SIM)请勿将喷嘴放入内部，否则会损坏 iPhone 的内部组件。
更新无线运营商设置
您可以通过更新 iPhone 的运营商设置来解决“未安装SIM卡”错误。(SIM)它们包含可能有助于正确识别SIM 卡(SIM)的基本说明。
问题 - 如果您的 iPhone 提示您这样做，您只能安装无线运营商更新。值得庆幸的是，有一种方法可以“推动”它这样做。
首先，连接到 Wi-Fi 网络。然后，转到设置(Settings )>常规(General )>关于(About )并等待几秒钟。如果您看到运营商设置更新(Carrier Settings Update)提示，请点击更新(Update)。
如果等待一分钟后没有显示任何内容，则您的 iPhone 的运营商设置可能是最新的。
更新 iOS
iPhone 系统软件（iOS）的过时版本可能会导致各种与网络相关的问题。Apple会迅速纠正已知问题，因此请考虑更新您的 iPhone。
前往“设置”(Settings ) > “通用(General )” > “软件更新”(Software Update )，然后点击“下载并安装(Download and Install )”以应用最新的 iOS 更新。
重置网络设置
由于网络设置不正确 ，您的 iPhone 也可能无法识别SIM卡。(SIM)
重置它们可以帮助解决这个问题，因此请转到“设置”(Settings ) > “通用(General )” > “重置(Reset )” ，然后选择“重置网络设置”(Reset Network Settings)。
网络设置重置程序(network settings reset procedure)将删除所有已保存的 Wi-Fi(Wi-Fi)网络和APN（接入点名称(Access Point Name)）设置。如果损坏的网络设置是问题的根源，那么您的 iPhone 应该会在此之后识别SIM 卡(SIM)。
检查损坏
如果您仍然在 iPhone 上看到“未安装SIM卡”错误，则应检查SIM卡或 iPhone 是否损坏。一种快速的方法是插入另一张SIM卡。
如果 iPhone 检测到它没有问题，则说明您手中的SIM 卡出现故障。(SIM)但是，如果它也失败了，那么 iPhone 本身就有问题。
联系无线运营商
致电您的无线运营商的支持服务（如果您还没有的话）并告诉他们问题所在。他们可以就您接下来必须做什么提供额外的说明和指导。您还可以在处理时排除与帐户相关的问题。
去苹果
如果上述修复都不起作用（并且如果联系您的运营商没有产生任何积极的结果），那么您的 iPhone 上的SIM卡读卡器可能存在缺陷或损坏。将其带到Apple Store进行维修或更换。
How to Fix “No Sim Card Installed” Error on iPhone
Your iPhone is quick to notice if you forget to put a SIM card in it. After all, you can’t send any text messages, make calls, or use cellular data without that tiny piece of metal and plastic. But what if the iPhone says “No SIM Card Installed” when there is one inside?
Many factors—such as a buggy cellular radio, outdated carrier settings, or a damaged SIM—can cause the “No SIM Card Installed” error to pop up on the screen. Most of the time, however, the reason is trivial, and you can swiftly resolve the issue.
The list of troubleshooting tips and fixes below should help you fix the “No SIM Card Installed” error on your iPhone.
Turn Airplane Mode ON/OFF
Rarely, the network-related components inside your iPhone can behave erratically for no particular reason. Luckily, you can get it to work again by toggling Airplane Mode ON/OFF.
Start by opening the Settings app on your iPhone. Then, turn on the switch next to Airplane Mode and wait for at least five seconds before turning it off.
That should reboot the iPhone’s network equipment and enable the device to recognize the SIM card.
Restart iPhone
If your iPhone continues to throw out a “No SIM Card Installed” error despite turning Airplane Mode ON/OFF, it’s a good idea to follow up with a device restart. That should resolve minor glitches or anomalies that prevent it from recognizing the SIM card inside.
Restart an iPhone With Face ID
Quickly press and release the iPhone’s Volume Up and Volume Down buttons one after the other, and immediately follow by holding down the Side button. Then, drag the Power icon to the right to shut down the device.
Wait for 30 seconds and hold down the Side button again to turn on your iPhone.
Restart an iPhone With Touch ID
Press and hold the iPhone’s Side/Top button and drag the Power icon to the right to shut down the device. Then, wait for 30 seconds and hold down the Side/Top button again to restart it.
Eject SIM and Re-insert It
Did you drop your iPhone? That could’ve ended up knocking the SIM card around, so it’s a good idea to eject and re-insert it.
Use the SIM-eject tool that came with your iPhone—a paper clip would also work—to remove the SIM tray. You should find it on the right side of the iPhone, but if you use an iPhone 12 or newer, look on the left side instead.
Then, remove the SIM card, reseat it on the SIM tray correctly (use the notch on the card and tray for guidance), and slide it back into your iPhone.
Clean SIM Card
If you have a habit of swapping your SIM card between devices regularly, it may have ended up getting coated in a layer of dirt. You should clean it.
Try wiping the SIM card, and then the SIM tray, with a soft, dry cloth. That should eliminate dust and grime stopping the SIM card’s connectors from making contact with the iPhone.
It’s also a good idea to clear out the SIM slot from debris with a few bursts of compressed air. Do not put the nozzle inside, as that can damage the iPhone’s internal components.
Update Wireless Carrier Settings
You can resolve the “No SIM Card Installed” error by updating your iPhone’s carrier settings. They contain essential instructions that may help it identify the SIM correctly.
The problem—you can only install a wireless carrier update if your iPhone prompts you to do so. Thankfully, there’s a way to “push” it into doing that.
First, connect to a Wi-Fi network. Then, go to Settings > General > About and wait for a few seconds. If you see a Carrier Settings Update prompt, tap Update.
If nothing shows up after waiting around for a minute, your iPhone’s carrier settings are likely up-to-date.
Update iOS
Outdated versions of the iPhone’s system software—iOS—can cause all sorts of network-related issues. Apple rectifies known problems quickly, so do consider updating your iPhone.
Go to Settings > General > Software Update and tap Download and Install to apply the latest iOS updates.
Reset Network Settings
Your iPhone may also fail to recognize a SIM card due to incorrect network settings.
Resetting them can help fix that, so go to Settings > General > Reset and select Reset Network Settings.
The network settings reset procedure will delete all saved Wi-Fi networks and APN (Access Point Name) settings. If corrupt network settings were at the source of the issue, your iPhone should recognize the SIM after that.
Check for Damage
If you still keep seeing the “No SIM Card Installed” error on the iPhone, you should check for damages to the SIM card or the iPhone. A quick way to do that is to insert another SIM card.
If the iPhone detects it without issues, you have a malfunctioning SIM in your hands. If it fails as well, however, there’s something wrong with the iPhone itself.
Contact Wireless Carrier
Ring up your wireless carrier’s support service—if you haven’t already—and tell them about the problem. They can offer additional instructions and guidance on what you must do next. You can also rule out account-related issues while you’re at it.
Go to Apple
If none of the fixes above worked (and if contacting your carrier didn’t yield anything positive), you’re likely dealing with a defective or damaged SIM card reader on your iPhone. Take it to an Apple Store for repairs or a replacement.
